A RED IN THE SHED (327)
A Major Rebuild Before the 2003 National Titles
When my race engineering shop started granting me ‘regular customer discount’ on engine and gearbox repairs, I knew that we were having a bad season. The piston failure that prevented a finish in the last race of Round 1 in March 2003 led to a prolonged layoff from racing. First, the preparation of road bikes for the fabulous Cape to Cape Grape Rally sapped much time and energy. Then the search for a suitable racing piston to suit the MAC’s plus 20 barrel took some time. And when a suitable high comp Mahle piston was found, it turned out to be standard bore so another barrel had to be acquired, sleeved and shortened to give the correct compression ratio.
While the engine was apart, I flushed every oilway and gallery to remove any trace of molten alloy from the failed piston crown. A return of the starvation problem that seemed to have been solved after some carb work last year finally caused the small crater that had formed in the crown to burn right through. The oil pump was dismantled and carefully reassembled after many hours spent grinding on glass plate to remove bow from the baseplate and ensure close to the specified 0.001” side clearance for all gears. At the same time the new single start worm gear was replaced by a good second hand one when I noticed that the incorrect tolerance on pitch of the worm was gradually being corrected in service by the oil pump pinion wearing a deep groove on one side of the flight. This explained the large quantity of fine bronze appearing in used oil.
I also toyed with the fitment of a remote float for the Monobloc and acquired an extended main jet holder and banjo for this purpose. But when I tried to find a suitable spot to mount the remote float I discovered why they are often bolted onto the front of the oil tank, as there isn’t a lot of space in the ideal location ie timing side (as I wanted to keep the integral float chamber on the drive side intact as a swill pot) beside or preferably in front of the carburettor. So attention turned to making the Monobloc work as is. I enlarged the hole in the fuel cap yet again and fitted a small bore hose to direct any surcharge to a safe place. I checked every passage betwixt tank and main jet and realised that in enlarging the float needle orifice last year and using a brass needle to suit, I had missed the bleeding obvious. On checking some standard Amal and SU float needles I saw that the cross section of the needle body was heavily fluted, whereas my brass needle was plain triangular in section. When viewed from the outlet end of the seat housing, the flow area remained restricted despite the larger orifice. So a trip to a motorcycling jeweler soon had the brass needle heavily fluted, which probably doubled the flow area. In parallel with this, a spare seat was enlarged both in the orifice and the guide and another oversized brass needle was manufactured. But it weighed about 3 grams compared to around 1 gram for the fluted brass needle and probably 0.5 grams for the standard Amal plastic needle. So the poor old float couldn’t lift it with enough pressure to seat, despite flow tests proving that the ‘Big Bertha’ needle and seat admitted 50% more flow to the float bowl than the original modified brass needle and seat. So a trip to Paul Barfoot’s lathe produced Big Bertha Mk2, which was hollow to just behind the conical end. This brought the weight down to around 2 grams, but still no joy in seating. So I then suspended it in the chuck of the bench drill and waisted the ribs of its flutes until it was guided only top and bottom (which is enough when you think about how a needle works). Success at last – Big Bertha sealed off reliably at a finished weight of around 1.5 grams. To be sure, to be sure as they say in Ireland, I also doubled the number of holes behind the filter on the inlet side of the seat housing and attacked the standard main jet holder, doubling the number of holes which admit flow from the float chamber to the reservoir under the main jet. At that point I was happy to run the Monobloc with Li’l Speedy’s new piston, in the knowledge that there was now little chance of any remaining bottlenecks in the fuel supply chain, thus ensuring a continuous supply of methanol under all racing conditions.
The return to the track for a Tuning Day in August was disastrous, with the engine seizing after half a lap. On stripping down I discovered that the only part of the lubrication circuit receiving flow was the big end quill and return to the tank ( hence the appearance of “everything normal” when checked by peering into the oil tank). The cam seized on the cam spindle and the spindle turned in the timing case, the cams were blue, both valves picked up bronze in the guides and the rocker shaft housings were heavily marked. The barrel needed honing by another thou and the piston needed to have heavy scuff marks removed.
So at the end of yet another unscheduled stripdown, which included the most detailed scientific disassembly you could imagine, I got as far as dismantling the oil pump and still found no immediate cause for the oil pump to have only lubricated the bottom end. I did notice that the ball valve spring was lightly kinked and may have become trapped beside the ball in the timing chest gallery, thus preventing it lifting fully off the seat. However knowing that on iron engines the ball valve is on the delivery side of the little positive displacement pump, even this theory didn’t fully explain the problem.
So I left the ball valve out and fitted a tap under the oil tank to prevent wet sumping. I also replaced the black rubber hose part way along the rocker feed line with a clear plastic piece, for visible indication of oil travelling northwards. And before starting the re-rebuilt engine I walked it with fuel tank off, plug out in first gear until oil emerged from the top rocker feed union deliberately left loose. Then, and only then, did I refit the tank, fuel up and bump start down the driveway, delighted to hear the crisp note that we all love. And even more delighted to lift the cap off the oil tank and see a healthy return flow appear almost immediately.
And so we were ready for the Father’s Day race meeting in early September, which turned out to be a successful day with few problems after some gentle running in during practice and the first couple of races. Being a wet day made it ideal for the return to the track with fresh engine.
Same story for the final round of the Club Championships in October, although gear selection problems saw Li’l Speedy jump out of top gear several times during the morning. Visual checks revealed the gearlever wasn’t fouling on anything (it had been touching the exhaust pipe at the end of travel and was corrected with some judiciously applied heat at the September meet). So back out we went with more deliberate footwork on the change from 3rd to 4th and it seemed better. But in the second race after lunch when on full song, it jumped out again and as I shut down the throttle I glanced down to see the tacho coming back from somewhere way beyond the vertical (which is where the needle sits at normal peak revs of 6500). To my surprise as I pulled off the racetrack to retire for the day, the engine picked up cleanly in a lower gear and felt 100% normal. But to stay out there would have been courting disaster, and I had no desire to embark on another stripdown with only weeks to go before the Nationals.
Then it was time for final preparations for the National Championships in early November, hosted in WA as part of a rotating cycle of venues around Australia. The gearbox came out and after diagnosing worn internal dogs on the sliding gear it was left with Don Chesson for a complete check. It returned a week later with a serviceable double sliding gear fitted, and a reshaped track in the selector plate to provide maximum engagement of this gear onto the splines of the sleeve gear when engaging 4th gear. I also lifted the head to see if valves had kissed piston. They hadn’t, but the exhaust valve leaked kerosene when I filled the exhaust port, so it came out and was lapped in to ensure a gastight seal. A thorough check over all vital parts, nuts and studs, chains and tyre pressures, wheel alignment, adjust brakes and clutch and we were ready for Practice and Qualifying on Friday 7th November.
For those who wanted more track time, the circuit was available on Thursday as well. I didn’t take advantage of this, but since I finished a meeting nearby at about 4pm decided to call by to see how Paul Barfoot’s latest project was running. This little flyer is a MOV racer with NSU flywheels and a very short rod. Last I saw it the barrel was down to two fins with more to come off the length. All the local Velos were parked up by the time I arrived but Paul was halfway through fitting a spare clutch to Mick Tesser’s MAC. Mick had been having trouble setting the clutch up after having the chainwheel bonded by the same shop that did mine earlier in the season. In typical Barfoot fashion, Paul brought a spare along just in case Mick had trouble. Then, when it was evident that it was needed, he sent Mick on his way and stayed back to fit it up so the bike would be ready for Friday’s official practice sessions.
There were two morning practice sessions and a mid afternoon qualifying session. After the first session it became clear that the machine to beat in the Period 2 Junior Class was Peter Dunster’s 1936 MAC. Peter (from Canberra) and brother Paul (from QLD) were enjoying their second visit to Barbagallo, having also made the long haul across for the 1998 Nationals. Being a spectator only at that meet, I recall being impressed by the pace of the swing arm framed, iron engined special which Peter campaigned in the Period 3 class. This machine was back again and in the ensuing years the rigid framed machine has been resurrected from the Newcastle area and campaigned successfully around the eastern tracks. The “as found” looks of this bike appealed to me, and I was not to be fooled into thinking that the mechanicals were anything but 100% race ready.
Practice session 1 resulted in some fun following local racer Harry Reynolds, out for the first time in Period 2 on a freshly built plunger framed ES2 Norton. Eventually we got around him and Li’l Speedy ran sweetly with no sign of the gear selection problems of the previous outing. Harry came into the pits grinning from ear to ear – much more fun than his G50 – enough time to think and yet fast enough to thrill. A Period 2 racing convert for sure. A check of times showed we were first 350 with a best lap of 1:25.69 with Peter Dunster second on 1:26.35. The Class record listed in the Program was 1:24.20, so we were circulating reasonably quickly and getting a feel for the conditions. It was quite hot, giving excellent grip.
Practice session 2 saw the pace quicken as Li’l Speedy’s gearbox gremlins now appeared to be completely solved. However I took note of some significant vibration through the footpegs between 4000 rpm and 5000 rpm. Fortunately they disappeared over 5000 rpm so I put it down to the slightly heavier Mahle piston. The footpeg vibes had been evident in the previous two meetings, but not as noticeable as today. Perhaps the change to a synthetic oil had some influence? I made a mental note to check the security of the engine and gearbox mounting bolts and the head steady after the session. Times were indeed quicker with a best lap of 1:24.42 but Peter Dunster had pulled out a hot lap over 2 seconds faster than Session 1, which put him well under the Class lap record with a 1:22.38. It was clear we’d have to dig deep in the afternoon’s Qualifying session to stay beside the flying MAC on the grid. But we had some in reserve, as Li’l Speedy had regularly run in the 1:22’s towards the end of season 2002, when a Period 3 start was all that was on offer. Our Club had not fielded a Period 2 class until the beginning of season 2003.
After a run over with the spanners and a chain lube in the pits, we were ready for the Qualifying session. For the first few laps we were circulating with one of the 500’s, which was hard to get by although it was slowing us up. Eventually we slipped by coming into the Basin and made it stick on the long drag up the hill, with Li’l Speedy’s tall 3rd gear again proving its worth as we crested the hill, grabbed top gear and got a slingshot ride down into the braking area for Novus corner and then a good run onto the main straight. With no traffic ahead this was going to be the lap. There were no mistakes and no-one baulked us so we ran a warm down lap and came in. No sense running hard for no reason – there were two more days of racing to come.
I was very pleased when I saw the Qualifying times – we’d cracked into the high 1:21’s but Peter had pulled another second off his previous best and scored a well deserved 350 Class pole on 1:21.29, a little over half a second ahead of Li’l Speedy. It was interesting to note that in a mixed field of unlimited, 500, 350 and 250 Period 2 machines, the two MAC’s qualified fourth and fifth, with only a Series A Vincent twin, a very fast Harley and a quick ES2 ahead of us – the rest of the 500’s and unlimited machines were further back on the grid. This is a tribute to the competitiveness of the racing Velo, even when based on the humble MAC.
While preparing for the warm up session on Saturday morning, I noticed methanol dripping from the right rear of the tank. The weld around the fuel tap socket had cracked, so it was off with the tank, dry it out and apply some of the magic epoxy putty. It was dry and held fuel in time for the first race. Neither of Saturday’s two races scored Championship points – this was reserved for Sunday’s events only.
Come race time we were ready and all seemed in order - we had oil circulating, no fuel leaks and a crisp throttle response. Warm up lap went by and then we gridded up at the head of the second row with Peter Dunster taking the inside spot on the front row. When the lights went out we got our usual conservative start, being swamped by the two slower 500 Nortons on the second row. At the end of lap 1 we were in sixth place, with Harry Reynolds in our sights. By lap 2 we’d moved past Harry and had the flying MAC 1.5 seconds ahead. As we came into the braking area to complete lap 3 we saw an opportunity to slip up the inside and try to outrun him down the straight. But as we exited the corner Peter looked down and pulled to the left of the track – his race over due to a mechanical problem. So we pressed on, getting onto the tail of the 3rd placed Norton through the esses and slipping by under brakes into the Basin. And again the 350 proved to have the legs on the 500 despite the long uphill drag out of the Basin. Two more laps and the chequered flag came out for a creditable third place. This would give us a great starting opportunity for the afternoon race, being up on the front row next to Kal Carrick’s big Vincent and Fraser McMillan’s fast ES2 Norton.
During the post race checkover I discovered that the magic epoxy had failed the race test. After draining the remaining fuel I asked around and found a handyman in one of the pit garages, who was set up for welding. After blowing the tank out with compressed air for at least ten minutes, he welded the fracture around the fuel tap’s threaded socket and we had a permanent cure, and a slightly less pretty paint job. Fortunately there was plenty of time between races.
A cameraman on the grid at the start of the afternoon race gave us a taste of how Valentino, Troy and the boys feel before a big race. Made a mental note to find out where he was from and get hold of some of the footage. We lined up for the start and within seconds of the red light fading Li’l Speedy was again surrounded and muscled back through the field, entering turn one in seventh place. We lost four places in the first 200 metres due to my reluctance to punish the clutch as much as I obviously should. Tucked in behind the Dunster MAC (which also stormed past off the line) we prepared for the job of working our way through the fast starting but slower 500’s that had beaten us to Turn 1. But a passing opportunity on lap 2 got us in front of Peter and then onto the tail of the fifth placed ES2.
By the end of lap 3 both MACs had passed both fifth and fourth placed Nortons, leaving us to circulate with little hope of catching the big Vincent, an indecently quick Harley (which had not appeared in the morning race) and the Mcmillan ES2. When the last lap board came out we were 10 seconds behind the 3rd placed Norton and I could see and hear the Dunster MAC range up alongside down the main straight. But we held our inside line and our nerve into turn 1 and started the last lap with Peter in hot pursuit. We led through the left hander, over skyline and down into the basin. We led up the hill and down into Novus, with the racing line covered. A mere moment after I decided that there was no need for any desperate late braking because he wasn’t coming up the inside, I heard a noise to the outside and with a wide swooping entry to Novus, Peter slipped by and led us onto the home straight. Despite getting on the power early out of Novus and holding a tighter exit, the best we could do was run up the inside of the flying 36 MAC as we approached the chequered flag, with the official time showing a 0.2 second gap between us. A good way to end Saturday’s non Championship races.
We returned to the track early Sunday morning and prepared for the warm up. On each day we were the first race of the day, so it was important to be on top of machine preparation. Li’l Speedy was running well, so , fuel tank welding aside, maintenance was confined to lubing and inspections, although I did check the tappet clearances at some stage over the weekend.
Race 1 was forgettable. The Dunster MAC was ahead of us on the grid. We got a better start but one or two 500’s came by and got between the two MACs. This caused us to lose time getting past, which we were able to do by the end of lap 1. But by then Peter had a 4 second break on us, having made the best of a clear opening lap. The gap grew a little each lap so we eventually settled back for a safe fifth place overall and 20 points in the 350 class Championship.
Following a chat with Don Chesson in the pits, the strategy for the final race was mapped out. Somehow, we had to be on his tail at the end of lap 1. Then we had a fighting chance.
We lined up for the final race. Peter had the last spot in the first row, Li’l Speedy had the first spot in the second row. I knew I had to use more revs and be prepared to punish that clutch. We got a great start but still a 500 Norton got between us before turn 1. Got right on his tail through the left hander with Peter only a few lengths further ahead. Lined up the Norton for an inside pass on the right hand kink coming into skyline when a fallen bike and rider suddenly appeared. Fortunately the big Vincent was sliding towards the inside of the track – we were towards the outside. We found a clear line through the debris and managed to execute the plan, coming back into spectator view right on the rear wheel of the flying Dunster machine. Don will be happy, I thought.
But it was to no avail as the officials red flagged us at the start/finish line to allow the marshalls time to clear the track. On the slow down lap we noted that the rider was sitting, awaiting the ambulance, but his beautiful Vincent was strewn over 50 metres – we found out later that the gearbox had seized.
Back at the dummy grid, they gave us an opportunity to top up fuel, so we returned to our pit area and topped up the tank – wouldn’t want to run out during the final race.
Back down to the dummy grid, another warm up lap and then we were back on the start line, with an empty space on grid position number 1, where the big Vincent had been.
I focused on the red light with the same determination to get off the line fast, but what unfolded was unfortunately not the same result as the aborted race. Over skyline we lined up the Norton but couldn’t get by. It led us into the Basin and won the drag to the top of the hill. At the end of lap 1 Peter led the Norton by 1.3 seconds with Li’l Speedy a further 0.4 seconds further back. Early on lap 2 we made our move on the Norton and started to claw away at Peter’s lead. But he was determined not to give an inch. The gap at the end of lap 2 went out to 1.9 seconds. Lap 3 was a ripper - by the top of the hill as we came into spectator view again we were gaining, but not quite on the back wheel of the Dunster machine. We crossed the line at the start of lap 4 only half a second down. At the start of the final lap the gap was only 0.1 seconds. But the battle was so enthralling that I didn’t see the last lap board. I actually thought we had 2 to go.
So we tagged the flying Dunster machine all around lap 5, plotting an overtaking move on the final lap. Problem was that this was the final lap. However I had decided that I could probably get up the inside out of Novus, run side by side across the start/finish line and then take the inside line into turn 1 and see if we could hold him off to the finish.
So in executing the first part of the flawed plan, I actually gave us a fighting chance, as we were already on a tighter exit line and gaining when I looked down the straight and saw the chequered flag being waved for the bigger machines in front.
Damn – there’s not enough time – or is there? I held Li’l Speedy in third and stretched that throttle cable as far as I dared but Peter was doing the same right alongside. The momentum we had was enough to get past, but alas not before the finish line, losing out by only 0.07 seconds. What a finish to our first National Championships.
A RED IN THE SHED (328)
Li’l Speedy’s 2003 National Championships, Perth WA (continued)
While preparing for the warm up session on Saturday morning, I noticed methanol dripping from the right rear of the tank. The weld around the fuel tap socket had cracked, so it was off with the tank, dry it out and apply some of the magic epoxy putty. It was dry and held fuel in time for the first race. Neither of Saturday’s two races scored Championship points – this was reserved for Sunday’s events only.
Come race time we were ready and all seemed in order - we had oil circulating, no fuel leaks and a crisp throttle response. Warm up lap went by and then we gridded up at the head of the second row with Peter Dunster taking the inside spot on the front row. When the lights went out we got our usual conservative start, being swamped by the two slower 500 Nortons on the second row. At the end of lap 1 we were in sixth place, with the Norton of Harry Reynolds in our sights. By lap 2 we’d moved past Harry and had Peter Dunster’s flying MAC 1.5 seconds ahead. As we came into the braking area to complete lap 3 we saw an opportunity to slip up the inside and try to outrun him down the straight. But as we exited the corner Peter looked down and pulled to the left of the track – his race over due to a mechanical problem. So we pressed on, getting onto the tail of the 3rd placed Norton through the esses and slipping by under brakes into the Basin. And again the 350 MAC proved to have the legs on the 500 despite the long uphill drag out of the Basin. Two more laps and the chequered flag came out for a creditable third place. This would give us a great starting opportunity for the afternoon race, being up on the front row next to Kal Carrick’s big Vincent and Fraser McMillan’s fast ES2 Norton.
During the post race checkover I discovered that the magic epoxy had failed the race test. After draining the remaining fuel I asked around and found a handyman in one of the pit garages, who was set up for welding. After blowing the tank out with compressed air for at least ten minutes, he welded the fracture around the fuel tap’s threaded socket and we had a permanent cure, and a slightly less pretty paint job. Fortunately there was plenty of time between races.
A cameraman on the grid at the start of the afternoon race gave us a taste of how Valentino, Troy and the boys feel before a big race. Made a mental note to find out where he was from and get hold of some of the footage. We lined up for the start and within seconds of the red light fading Li’l Speedy was again surrounded and muscled back through the field, entering turn one in seventh place. We lost four places in the first 200 metres due to my reluctance to punish the clutch as much as I obviously should. Tucked in behind the Dunster MAC (which also stormed past off the line) we prepared for the job of working our way through the fast starting but slower 500’s that had beaten us to Turn 1. A passing opportunity on lap 2 got us in front of Peter and then onto the tail of the fifth placed ES2.
By the end of lap 3 both MACs had passed both fifth and fourth placed Nortons, leaving us to circulate with little hope of catching the front runners (the big Vincent, an indecently quick Harley which had not appeared in the morning race and the Mcmillan ES2). When the last lap board came out we were 10 seconds behind the 3rd placed Norton and I could see and hear the Dunster MAC range up alongside down the main straight. But we held our inside line and our nerve into turn 1 and started the last lap with Peter in hot pursuit. We led through the left hander, over skyline and down into the basin. We led up the hill and down into Novus, with the racing line covered. A mere moment after I decided that there was no need for any desperate late braking because he wasn’t coming up the inside, I heard a noise to the outside and with a wide swooping entry to Novus, Peter slipped by and led us onto the home straight. Despite getting on the power early out of Novus and holding a tighter exit, the best we could do was run up the inside of the flying 36 MAC as we approached the chequered flag, with the official time showing a 0.2 second gap between us. A good way to end Saturday’s non point scoring races.
We returned to the track early Sunday morning and prepared for the warm up. On each day we were the first race of the day, so it was important to be on top of machine preparation. Li’l Speedy was running well, so fuel tank welding aside, maintenance was confined to lubing and inspections, although I did check the tappet clearances at some stage over the weekend.
Race 1 was forgettable. The Dunster MAC was ahead of us on the grid. We got a better start than in Saturday’s races but one or two 500’s came by and got between the two MACs. This caused us to lose time getting past, which we were able to do by the end of lap 1. But by then Peter had a 4 second break on us, having made the best of a clear opening lap. The gap grew a little each lap so we eventually settled back for a safe fifth place overall and 20 points in the 350 class Championship.
Following a chat with Don Chesson in the pits, the strategy for the final race was mapped out. Somehow, we had to be on his tail at the end of lap 1. Then we had a fighting chance.
We lined up for the final race. Peter had the last spot in the first row, Li’l Speedy had the first spot in the second row. I knew I had to use more revs and be prepared to punish that clutch. We got a great start but still a 500 Norton got between us before turn 1. Got right on his tail through the left hander with Peter only a few lengths further ahead. Lined up the Norton for an inside pass on the right hand kink coming into skyline when a fallen bike and rider suddenly appeared. Fortunately the big Vincent was sliding towards the inside of the track – we were towards the outside. We found a clear line through the debris and managed to execute the plan, coming back into spectator view right on the rear wheel of the flying Dunster machine. Don will be happy, I thought.
But it was to no avail as the officials red flagged us at the start/finish line to allow the marshalls time to clear the track. On the slow down lap we noted that the rider was sitting, awaiting the ambulance, but his beautiful Vincent was strewn over 50 metres – we found out later that the gearbox had seized.
Back at the dummy grid, they gave us an opportunity to top up fuel, so we returned to our pit area and topped up the tank – wouldn’t want to run out during the final race.
Back down to the dummy grid, another warm up lap and then we were back on the start line, with an empty space on grid position number 1, where the big Vincent had been.
I focused on the red light with the same determination to get off the line fast, but what unfolded was unfortunately not the same result as the aborted race. The same Norton got between the two MACs before turn 1. Over skyline we lined him up but couldn’t get by. It led us into the Basin and won the drag to the top of the hill. At the end of lap 1 Peter led the Norton by 1.3 seconds with Li’l Speedy a further 0.4 seconds further back. Early on lap 2 we made our move on the Norton and started to claw away at Peter’s lead. But he was determined not to give an inch. The gap at the end of lap 2 went out to 1.9 seconds. Lap 3 was a ripper - by the top of the hill as we came into spectator view again we were gaining, but not quite on the back wheel of the Dunster machine. We crossed the line at the start of lap 4 only half a second down. At the start of the final lap the gap was only 0.1 seconds. But the battle was so enthralling that I didn’t see the last lap board. I actually thought we had 2 laps to go.
So we tagged the flying Dunster machine all around lap 5, plotting an overtaking move on the final lap. Problem was that this was the final lap. However I had decided that we could probably get up the inside out of Novus, run side by side across the start/finish line and then take the inside line into turn 1 and see if we could hold him off to the finish.
So the execution of the first part of the flawed plan actually gave us a fighting chance, as we were already on a tighter line with a faster exit speed than Peter when I looked down the straight and saw the chequered flag being waved for the bigger machines in front.
Damn – there’s not enough time – or is there? I held Li’l Speedy in third, got down under the top layer of paint on the tank and stretched that throttle cable as hard as I dared but Peter was doing the same right alongside. The momentum we had was enough to get past, but alas not before the finish line, losing out by only 0.07 seconds. What a finish to our first National Championships!
By the time we passed the end of the control tower only 10 metres past the finish line Li’l Speedy’s wheel was in front. But the opportunity for a draw on points was lost. Peter was the deserving winner, 50 points to 40. Roll on season 2004.
A RED IN THE SHED (332)
Li’l Speedy’s National Titles, Winton, VIC 2004
Part 1 – Preparations
Early in season 04 Li’l Speedy suffered a major mechanical failure in the engine department. This occurred towards the end of a Club Day at Wanneroo with little warning, the only tell tale sign being that the magneto mounting nuts loosened not once but twice during the day. After the second incident I decided to park it up and investigate later, as it was by now accompanied by a clattering sound at idle, which I put down to the steel magneto drive gear contacting the back face of the timing chest, which it could do if the magneto was able to tilt during operation. No doubt a more experienced rider/mechanic may have detected other signs of the root cause of this problem, but unfortunately I was not in tune to the changed vibration and noise which must have foreshadowed what was to follow.
When I finally got to look inside some weeks later, I was aghast at what I found inside the timing chest. The flights of the oil pump worm and a chunk of the steel pinion were lying in a pool of bronze gunk in the base of the chest. The cams and bottom followers were blue. I removed the steady plate and started putting parts in the tray, wondering what had caused this latest malady. Having got the cams and idler gear out, I grabbed the end of the mainshaft and found 1/8”free movement - a timing side main bearing failure was the cause of this mess. An hour later the engine was on the bench and the oil pump was out and dismantled, revealing that a piece of the broken ball bearing had gone into the suction side, jamming the gears, hence the broken pinion on the oil pump drive and the lack of flights on the bronze worm. I resolved to develop a method of stopping this from happening again. Something better than the factory’s ‘suction filter plug’ and the racer’s ‘no suction filter’ approaches. I figured that the magneto must have worked loose because of the cyclic load being transmitted up through the train of timing gears on each upward stroke of the piston, when the crank was no longer properly supported by the main bearing. Close inspection of the steel gears revealed no visible damage and fortunately the bushings of the camwheel and idler gear were still within tolerance, a tribute to the robustness of the design. I also concluded that although the bearing may have been on its way out for a while, the oil pump failure must have occurred on the warm down lap or when re-entering the pits, as Li’l Speedy’s engine would otherwise have seized solid if oil flow had ceased at race pace.
During the period of chasing down spares that followed, I decided to go the whole hog and take up Don Chesson’s offer of a newly cast strengthened drive side crankcase. This would allow me to bump the compression ratio up another notch without fear of breaking the drive side crankcase (the need was driven home by the remarks of experienced competitor Peter Dunster when he was looking over Li’l Speedy’s racing modifications during the 2003 Championships – “I see you’re still using a hand grenade crankcase”, a reference to the standard drive side case I was using.) A replacement oil pump appeared courtesy of Norm Trigg and over the following weeks all the damaged bits were either repaired or replaced and the rebuild began. An unexpected problem arose with the oil pump – when the original (now scrap) pump was removed, it required modest heat. After the rebuild, with the same drive side case, it was a cold fit. And so was the new pump Norm supplied. There followed a series of measurements of different pump bodies and crankcase bores available in workshops in Glen Waverley and Perth, with the conclusion being that there is a range of diameters and bore sizes over a 3 to 4 thou range which have to be matched. So the rebuilt engine, now with c.r. a healthy 12:1, roller bearings both sides of the crank and titanium pushrods, was temporarily fitted with the new cold fit pump. Arrangements were made to call by Norm’s to fit a slightly larger diameter pump before heading to Winton. I bumped the engine into life in the driveway and observed a satisfactory oil return before loading Li’l Speedy and a swag of tools onto the trailer for the big trip across Australia. When the cases are cold and the oil thick, the problem of oil short circuiting around a poor fitting pump is an academic one only – but for road or race use the fit must be good. I also packed a coil spring which was a neat fit in the crankcase suction gallery and an off-cut of fine brass mesh with which to fashion a foolproof suction filter when I had a quiet moment in Melbourne.
Part 2 – The Mission
The decision to enter the 2004 Australian Championships was borne of exasperation and frustration. Having been on a winning streak in the first two rounds of the 2004 Club Championship, I was keen to get back for the fourth and final round in October to secure Li’l Speedy’s first class win in a Club Championship. Then I discovered that this meeting clashed with the Good Companions Rally at Bright, VIC, which I had entered. Torn between conflicting commitments 3600km apart, I tossed around several ideas, none of which were satisfactory. Then an envelope arrived in the mail, with entry forms for Winton, which happened to be on the weekend after the Bright bash. And then at work, I was notified of a booking for a training course in Melbourne in the week between these two events. So the die was cast – forego the Club Championship in exchange for another shot at the Australian title and a great weekend in the Victorian high country the preceding weekend.
So it was that at dawn on Friday 22 October the great solo transcontinental journey began. I had 3 days to cross the continent and be ready for work in my employer’s Melbourne office on Monday morning.
The tow wagon was our 2002 model Peugeot 307 Hdi. This is powered by one of those modern high speed turbo diesel engines that the European manufacturers have turned into an art form in recent years. The advent of better engine management computers and high pressure common rail injector technology have led to jet-like on road performance coupled with incredible frugality from its 2 litre powerplant (a claimed 4.0 L/100km on highway cycle – that’s a whisker over 70mpg in the old language!). Their modest power / high torque characteristics make them ideal for towing. And the Pug’s supple ride, low NVH and standard creature comforts (climate control, CD player, front seat armrests, height and reach adjustable seat and steering wheel) mean that it can be set up for any driver to tackle long distances with minimal fatigue. Essential spares included a fan belt, 5L of radiator coolant and a stick of magic epoxy putty (for use in case of us tangling with wildlife in the middle of nowhere).
The battle plan for the mission was simple – Day 1 = 1200km Perth to Cocklebiddy. Day 2 = 1200km Cocklebiddy to Port Augusta. Day 3 = 1200km Port Augusta to Melbourne.
The mind can play tricks after a long day at the wheel, especially when dusk falls on the western edge of the Nullarbor Plain. The day had been a breeze, with a 5:35am start from Perth, one fuel stop as the first 800km ticked up on the odometer, and a couple of comfort stops. I had quickly adopted the habits appropriate for a long distance mission, eating and drinking on the go and generally minimising the time stopped in order to keep the hourly averages up where they need to be if you are to pack 1200kms into the daylight hours. Another trick I discovered by accident, which helped to stay focused during a long day at the wheel, was to keep an hourly log from the minute of departure.
Anyway, the last 60kms into Cocklebiddy was seriously risky, with kangaroos on the move, and in one instance just sitting right in the middle of the road. With senses sharpened and speed reduced, we made it safely into the welcoming forecourt of the Cocklebiddy roadhouse, but not before severe eyestrain and mind tricks had set in. During this period I coined a phrase to describe the frantic brain activity – “Is that a roo or an rso?” RSO being an acronym for Roo Shaped Object, of which there were plenty seen among the saltbush plains when the brain became overactive.
Day 2 began at 5:20am local time, Cocklebiddy being in an unofficial time zone half an hour ahead of the rest of WA. I decided to put some distance away before stopping for fuel 2 hours down the road, 1400km from home. An hour or so out from the SA border I remembered that I had fruit left over from yesterday, so in the course of the next hour downed two bananas and an apple to avoid having to throw them in the border guard’s bin. After passing into SA, the coast of the Great Australian Bight comes up to the highway and so I ventured in to several of the viewing points for photos and a lung full of fresh Southern Ocean sea air. We made Port Augusta just on dusk, but thankfully without a repeat of yesterday’s roo-dodging conclusion.
On day 3 the wheels began to turn at 5am. By 8am we were traversing the still sleeping outer suburbs of Adelaide and were soon over the Hills, heading for the Victorian border on the rhumb line to Melbourne. By 2pm I decided we were sufficiently ahead of schedule to deviate via Bendigo to catch up with some old friends, before completing the journey to Melbourne. The entourage pulled into the driveway of Richard Fanning’s eastern suburbs home at 6:45pm, having covered 3,564kms since leaving Perth. Mission complete with no bumps, no scratches – not even a windscreen chip to show.
Part 3 - Final Pre-Race Preparations
While I checked over chains and wheel alignment, Richard’s workshop skills were put to good use making the suction filter. The plan was to solder a disc of mesh onto the end of the spring, then insert the spring, (mesh end first) into the oil return gallery. Upon tightening the drain plug, the spring would push the mess firmly against the upper end of the gallery, thus ensuring that any lumps of metal which enter the gallery from the lateral crankcase drilling, cannot enter the small bore inlet to the oil pump return. It would also be easy to remove and clean. A precautionary test with cold, heavy oil showed that the mesh offered virtually no resistance to oil flow when in a clean condition. After some fiddling, the new filter was fitted and when the engine was fired up a healthy return oil flow indicated that the filter was having no unplanned side effects.
The next night Li’l Speedy was back on the trailer and off to Norm Trigg’s shed for an oil pump changeover. He was busy preparing a special wide trailer to get the Velo outfit safely to the following weekend’s rally. But he interrupted proceedings long enough to help with the oil pump. I chose one which was a 1.5 thou interference fit in my cases, and this went in first go with the engine still in the frame, much to Norm’s surprise. As I waved the oxy torch over Li’l Speedy’s bottom end, Norm stood back, somewhat cynical about the chance of success, asking a string of unsettling questions. What if it only goes in half way? Have you got any long bolts to guide it in? Have you done this with the engine in the frame before, because I’ve only ever done it with the engine out? I didn’t have time to consider the full ramifications – I just knew the cases had to be hot enough and I was acutely aware that I only had one shot to push the pump home and get the first 2 studs in for proper alignment. Otherwise there’d be a lot of time wasted re-heating cases to a higher temperature, removing and cooling the pump body then trying again.
A final shakedown run up and down Closter Ave before departing for Winton the following week showed that all was well, although I’d need to use the practice sessions to bed in the new bearings (and learn the track) before using full throttle under race conditions.
On a wet Thursday evening the tow wagon headed north for a rendezvous in Benalla with my pit crew for the weekend, retired Velo racer Ted Hicks, before heading for our digs, shared with a bunch of other West Aussies at Wangaratta.
Part 4 – Friday Practice & Qualifying
Low scudding clouds marked the short drive from Wangaratta to Winton on Friday morning. On arrival at the track we soon found our pit garages, hired by the WA Club for the weekend, and passed through a wet scrutineering bay with appropriate ticks in boxes and stickers issued. The main disappointment was the shortage of Period 2 Junior class machines on the entry list. We were, until then, unaware that east coast racing politics had seen many potential entrants stay away. So again we were faced with racing in a non-championship event. But arch rival from 2003, Peter Dunster was there with his rapid pre-war MAC, so we would get to have some fun one way or another.
The racing was held on the long track, as used by the V8 Supercars, so this left us with the confusing prospect of having 2 start lines and 2 pit entry points to choose from, however this was soon clarified as all races started from the new start line and we were at liberty to use either pit entry. A benefit of the smaller than expected fields was that the final programme packed in an extra race on each day, which was good, except for the fact that we’d pre-ordered our supply of methanol based on the preliminary race programme. With only 20 litres for practice, qualifying and racing, I was unsure if it would be sufficient, although I had 5 litres brought from home, stashed in the trailer if needed.
We went out for the morning practice sessions and put in half a dozen exploratory laps each time without incident. Gearing seemed too tall for the tight back section so before the first qualifying session we went from a 21 tooth to a 19 tooth gearbox sprocket.
After this change, our best lap time in the qualifying session was 2:02, which was respectably midfield and ahead of many 500’s and unlimited machines, but some 7 seconds per lap slower than Peter Dunster. We went home on Friday evening satisfied with the day’s work and contemplating the racing to come.
Part 5 – Saturday Qualifying & Racing
Saturday’s weather was similar to Friday’s. In fact the second qualifying session was wet, so times blew out to 2:16 for me and 2:11 for Peter. So in the wet, the gap was a little closer, although not close enough for my liking. But now the gearing felt too short, needing a 100m stretch of top gear towards the end of Falken Straight, before going back to second for the two tight right handers leading onto the new start/finish straight. So we changed to the 20 tooth sprocket and settled on this for the remainder of the weekend. This proved to be just right for this section, with third gear now peaking at a shade over 6500rpm as we reached the braking point.
After lunch we gridded up for the first non-championship race. Track conditions were damp but improving. By the end of the race lap times were similar to the first (dry) practice session. Li’l Speedy finished 8th with a best lap of 2:02, while Peter finished 4th with a best lap of 1:58.
Later in the afternoon we were back out for the second of the non-championship races, this time with a better grid position. We were in position 8, directly behind the Dunster MAC in position 4. But the larger capacity machines behind us on the grid swamped us off the line so we had to work hard to get up to 9th at the end of lap 1. Track conditions were damp again, demanding caution to avoid the occasional pool of water near the inside of the racing line. We worked our way up to 6th, one place behind the Dunster MAC by the end of lap 3, but a lapse into complacency on the last lap allowed two of the larger capacity machines to re-pass, leaving us with a creditable 8th place, but disappointed not to be better placed. Best lap time in these damp conditions was in the high 2:08’s, matching for the first time the Dunster MAC. Perhaps a wet Sunday would be our only hope of challenging for the 350 class win in the Championship races.
Part 6 – Sunday Racing
Sunday’s programme gave us 3 more races, with only the latter two scoring points for the National Championship. By now, I had become confident that the oil pump was pumping, the new mains were bearing up under race conditions and the gearing was as good as we could get for the variety of corners and lengths of straights this circuit had to offer. So it was down to me to improve lap times.
Li’l Speedy started race 3 from position 8, yet again. And again we were swamped off the line, having to battle as number four in a tight pack of 4 unlike machines to get back into 10th spot at the end of lap 2. We were then confronted by a problem – a battle with Ted Dexter’s pre-war 500 cammy Norton, which had the legs on Li’l Speedy on the straights but wasn’t as quick through the curves, particularly the tight back section of the old circuit, which is shaped like a capital M. There is a tight right hander (Penrite Corner) followed by a short straight, a tight left, another short straight then the final tight right (Kumho Corner) before the Dunlop Straight. We sat in behind the Norton for laps 2 and 3, both putting in 2:01’s, then on lap 4 ran around the outside on the back section, just to let him know we were there. Ted responded with a fastest for the race 1:59.9 on lap 4, but in pressing on harder he revealed the Norton’s Achilles heel – a lack of ground clearance on the right hand side of the machine. A shower of sparks and a wobble gave the game away so all we had to do was wait for an appropriate opportunity. This came on the final lap, when we closed up hard on the back wheel running into Penrite, got a fast exit and ran up the outside of the Norton through the tight left hander then stayed there on the short straight, thus taking the inside line through Kumho corner. With the Norton’s lack of ground clearance on this side, Ted had no response to this. But I knew his opportunity would come on the run down Dunlop Straight. Li’l Speedy’s fresh engine felt strong so I abandoned the 6500 rev limit and ran out to 7000rpm in second and third, all the time waiting to hear the sound of the 500 Norton ranging up along side – but thankfully it was enough to hold him off. We crossed the finish line 0.7 seconds clear, thrilled to win our little “race within a race”. As we rode back into the pits, a cheery wave to Ted on the Norton yielded a thumbs up and a grin from ear to ear – he obviously enjoyed the battle too.
While refueling and running a spanner over Li’l Speedy in preparation for the afternoon’s two Championship races, an announcement came over, advising that our remaining races would be shortened from 6 laps to 4 laps. This was welcomed from a fuel conservation view, but meant that we would have less time to recover from our notoriously slow starts. The weather was clearing with the track now completely dry, so our hopes of making up the 5 second per lap deficit on the Dunster MAC were shot to pieces. But that doesn’t mean we couldn’t go out and have some more fun with whoever was lapping in the 1:59’s, a group which included West Australian Joe Zappa’s quick ES2 Norton, Bill Brice on the Redgrave Motorcycles Harley Davidson, Brian Gray’s BSA Silver Star and of course the Dexter Norton. In fact with the leading three or four machines typically finishing races with 5 to 10 second gaps ahead and behind across the finish line, we were having the fun of racing at close quarters while they were circulating in an efficient but lonely manner.
As we completed the warm-up lap for leg 1 of the Championship I snicked Li’l Speedy into neutral (or so I thought) as we coasted towards our grid position. Unfortunately when I let the clutch out there was a lurch and the engine stalled, leaving me with a potential problem at the worst possible time. So I quickly dismounted, engaged first, pulled back off compression and pushed, preying that the engine would fire without locking up the back wheel and before my solo pushing power on flat ground was exhausted. My prayer was answered with an immediate burst of life and before the tail enders reached their grid positions we had paddled back to our allocated spot on the grid, engine blipping crisply, this time with gearbox in the real neutral.
We got a good start this time and by the end of lap 1 had worked from 9th to 7th position, tucked in behind the Zappa Norton and the Brice Harley, witnessing some incredibly desperate late braking from the Harley as he challenged Zappa through the tight bits, ungainly as it looked with its hand gear change. There were occasions when I thought about overtaking but as soon as I tried any outbraking maneuver, he’d ease off the brakes and somehow manhandle the monster around the looming corner. I then sat back, deciding it was better to wait for a mistake, rather than risk it. My opportunity came on the second last corner of the race, when he tried to make a move on the Zappa Norton, but ran wide on the exit, crossing one of the remaining puddles in the process. We held a tight line, slipped by then made a super quick entry through the right hander onto the finish straight, and again revved the little 350’s heart out in second and third to beat the now recovered and fast closing Harley across the line by half a second. This finish gave us our best grid position for the final race – starting off number 6. It was also the first race where all laps after lap 1 were in the mid 1:59’s. In comparison the Dunster MAC finished fourth, putting in a fastest of 1:54 dead in these dry conditions.
The second leg of the Championship was a cracker. We lost some places on lap 1 but the field soon sorted itself out into the leading three, strung out ahead of the Zappa Norton, the Brice Harley, the Gray BSA and Li’l Speedy. For the first 2 laps this battling group of 4 was covered by 3.6 seconds, but on lap 3 we managed to pull closer to the tail of the Gray BSA, leaving only 3 seconds to the 4th placed Zappa Norton. A frantic last lap, which saw both the Harley and the BSA jousting with the Zappa Norton for a safe overtaking opportunity resulted in the 4 of us closed up nose to tail for an exciting finish. Despite each rider’s best efforts, the order remained as it began, but with only 1.5 seconds covering fourth to seventh places. This was a great way to end the weekend, with Li’l Speedy accounting well for itself among a field of larger capacity machines. A post race analysis of lap times showed that Li’l Speedy recorded the fastest lap of all 4 machines in this enthralling battle, an indication of how important the first few hundred metres of every race is. Get a clean start and lap 1 will be a quick one. Get a poor start and you’ll end up battling to make up time for the remainder of the race.
The most gallant performance of the weekend was that of Peter Dunster, whose rapid MAC finished third in the unlimited class, behind the two very quick Harley’s of Simon Thomas and Gary Lawton. In chatting with Peter later, our only disappointment was that the number of entries again failed to provide us with a Championship Junior Class. Here’s hoping that more 350’s will turn out in future National Championships.
A RED IN THE SHED (336)
A Top End Overhaul For Season ‘05
With some re-engineering by Don Chesson (new inlet guide to suit latest "extreme racing" inlet valve and to shorten and fit a new exhaust valve) and a few late nights in the shed during re-assembly, Li'l Speedy fired up with its new TT carb fitted at 5pm Saturday. Loaded the trailer at sunrise Sunday and off to the track for Round 2 of the Club Championships.
Had set the TT with 940 main (same as used successfully in the Monobloc), needle on middle groove and went out for first practice. Ran OK but lacked pulling power. Read plug (wrongly as it turned out), lowered the needle 2 notches and went out again. Li'l Speedy ran worse. Raised needle to position 7 after conferring with Don but could only try in the warm up area (first gear only) before race 1, but it felt better. In race 1 it bogged down off the line (nearly stalled) so got away last. Got onto the back of a group of 3 and could catch them around the back of the circuit but lost 'em down the straights - still not producing the power it should.
Having discovered the suspected cause of the Monobloc starvation problem mysteriously reappearing last season (a pinched breather hose to the fuel cap that would blow air when tested but when I sucked from the tank end the previously pinched section closed up like a check valve) I was keen to try the Monobloc with my patented ram air tank breather, a small gauze covered funnel pointing forward with a 1/8th hose tail and PVC tube to the fuel cap - actually an idea stolen from NSU race bikes of the 50's, but I'll bet they didn't use brass BSP fittings. I mounted this beside the tacho. So back on with the Monobloc, fortunately remembering to swap the main jet from the TT.
Race 2 I was counting the laps down to see if it would starve half way round lap 3 as it had done in my 2 or 3 attempts at racing in season 05. I was elated when lap 4 passed with no sign of a starvation problem so then I was able to concentrate on the race rather than the bike - a vital switch of priorities that is fundamental to success on the track. On lap 5 some cheeky guy came up the inside of us on the entry to turn 1 so I eased off the brakes, ran a little wide to give him space, got on the power early and was half a length in front with the inside line for the run into the esses by the time we exited the turn. This was the moment that signalled the message - Li'l Speedy's back! Finished the race with a gap on the guys who were snapping at our heels and on the tail of a faster group. The TT can stay in the parts bin - the Monobloc is king for Li'l Speedy.
Had a better grid position for race 3 and got a great start, stuffing it up the inside of a group of 4 on the entry to turn 1 and sitting right on the back wheel of Nick Chesson on the Mk7 KTT by the time we reached the exit. That thing revs to 7500 and has real grunt, but through the tight bits he was holding us up, so on lap 3 we slipped up the inside on the entry to turn 1 and held it flat in 3rd through the esses covering the fastest straight line through, as I could the hear roar of the KTT hot on my tail and knowing it had more power I was keen to prevent a pass / re-pass situation. We managed to build a gap on the KTT through the tight section at the back and in another lap started to run down a fast 350 BSA and the leading bike, a 36hp girder forked plunger ES2, with Manx front brake and gearbox internals - a very fast vintage racer. I could catch this pair in the tight bits but lost a few lengths down the straight. Then on lap 5 of 7 I found a neutral instead of third on the downchange on the entry to turn 1 and when I found a gear it was second, not third, and we were out wide so we lost about 30 metres on the leading pair. I almost settled for a comfortable 3rd place at this point but regained composure and figured we could just brake a littler later and see how much of this gap we could close up. That worked, so by the end of lap 6, with the final lap board showing, we were back in with a chance. We tagged them round the back of the circuit and made sure that on the second last turn we were on the back wheel of the second placed BSA. We ran hard down the hill to the final corner, waiting for one of them to make a mistake, but they both held their composure. As we entered the last turn nose to tail, I took my preferred late apex / early on the gas line and tucked up the inside of the BSA's rear wheel, wide open in 3rd as we exited the corner . Li'l Speedy carried some corner speed and the advantage of being on the power sooner to pull level by the time we were on the main straight, but the BSA began to inch ahead. But then he needed another gear while Li'l Speedy was till winding out in 3rd (thank God for that 17 tooth sleeve gear) and that was enough to pull us half a wheel ahead with the finish line fast approaching. But then I looked at the tacho and with something near 7000 rpm showing and the finish line only 20 metres away, decided we had enough momentum to grab 4th gear without losing the slender lead on the BSA. But alas I was wrong - my gear change giving the BSA second place by half a wheel.
Iron MACs on methanol are the sweetest thing. Stay tuned for Round 3.
A RED IN THE SHED (342)
After Round 3 ’06, a Long Break from Racing
What has happened to Li’l Speedy?
You may recall from FTDU336 that Round 2 of the 2006 season saw a return to the track trialling a TT carb after a recurrence of the Monobloc starvation issue during season 2005. This trial was only partly successful so the Monobloc was refitted and the new ram air system that pressurises the fuel tank proved to be a winner, so by the last event of the day the racing continued in earnest, with performance back to the standards of 2004.
So we turned up for Round 3 on the first Sunday in July ‘06, keen to mix it with the fast ES2 and the mid 50’s B31 that we diced with in Round 2. Practice was taken gently with Wanneroo long circuit lap times in the 1:27’s putting us in the slowest group for the “all classes” non-championship race that started proceedings. The slow practice time placed us well down the grid and with all the traffic we finished this 6 lap race some 15 seconds behind the ES2 and 12 seconds behind the B31, but we were able to foot it with a 1961 350Manx, which was running consistent 1:24’s while our lap chart showed laps 2, 3 and 4 in the 1:25’s with laps 5 and 6 down into the 1:23’s. Once into the real racing for the day, we would need a string of these latter times, or better, to be anywhere near our two sparring partners from Round 2.
After a thorough once over in the pit bay and a top up with methanol, we lined up for Leg 1 of our point scoring races, intent on being with the ES2 and B31 on the first lap – no use spending the whole race playing catch up. When the red light went out Li’l Speedy leapt off the line and into turn 1 on the tail of the ES2, with the B31 close behind. As we started lap 2 we were 1.2 seconds adrift of the ES2 but held a 1.5 second advantage over the B31. Being intent on hanging onto the ES2, lap 2 was quick, at 1:22.3, but still we lost a further 0.2 seconds. However our break on the B31 grew to 2 seconds, comfortable enough to simply concentrate on running the ES2 down, or wait for rider Joe Zappa to slip up somewhere. But as I grabbed top gear at the top of the hill on the back straight, Li’l Speedy faltered. My first thought was that fuel starvation had returned, but as I backed off and listened closely, the misfire continued, so maybe this wasn’t starvation after all. We moved to the left and peeled off into the pit exit, allowing the B31 to finish the race without the fun of a two or three way dice. He finished the race 6 seconds behind the ES2, with a fastest lap of 1:22.7, still 0.4 seconds down on our quick second lap.
On return to the pits I checked the tank vent (no problem there), the fuel taps (ditto), then the float bowl inlet filter and main jet for signs of blockage, but found nothing. Experience has shown to start at the top and work down when tracing fuel supply issues. Attention then turned to the magneto and sure enough, when I removed the contact breaker assembly, the eagle eyed Paul Barfoot noticed that there was a scuff mark on the points return spring. This was thought to be a possible cause of the misfire, if it had been earthing out on the cam ring. An inspection of the cam ring showed that this had occurred, so after adjusting the spring in its slot and Loctiting the tiny grub screw in place, I fired Li’l Speedy up in the warm up area and was happy to get a crisp response with no sign of the misfire. Smiles all round – now to get mentally prepared for the last race of the day.
We gridded up beside Joe on the ES2 and Wayne on the B31. Got another great start but Joe was on a mission, opening up a 1.8 second advantage at the end of lap 1, while hot on our tail, the B31 was only 0.3 seconds behind as we roared past the finish line for the first time, into top gear briefly before braking hard and down changing for the deceptively shaped turn 1. We pulled back 0.8 seconds on the ES2 on lap 2 and opened up a 0.5 second lead on the B31, so things were shaping up for a close battle towards the end of the race. A touch of complacency must have set in towards the end of lap 3, because as I braked for turn 7 and the all important entry onto the main straight, the B31 came around the outside, balking our run onto the main straight. Damn - now we’d lost a place and all of the ground we’d made up on the leading ES2. This mistake cost an extra 1.4 seconds compared to the previous lap time. Knuckling back down to the task for lap 4, we recovered nearly half a second on the ES2, but the B31 stayed between us so we passed the “last lap” board with some serious work to do if we were to improve our placing.
We got out of turn 1 hard on the throttle in 3rd, through the esses in a line as close to straight as possible, peaking out at 6,200 rpm before braking into the tricky uphill left hander. Out of the left hander we moved to the right of the track, peaking at 6500 rpm (85 mph with the 21 tooth sprocket fitted) through the right hand kink before changing to fourth over skyline and rocketing down into the basin, getting close onto the back of the B31, who was similarly closing on the leading ES2. As Joe exited the basin, a 180 degree corner with its apex in the sag of a gully, he heard the approaching threat, so pulled hard on the throttle wire and used the extra power of the 500 to gap us, as we smaller 350’s tried vainly to stay in his slipstream, at least to the top of the hill. Li’l Speedy is good on this section, with the long, straight exhaust pipe giving lots of mid range grunt, and the close ratio gear cluster allowing 3rd gear to be held until just over the crest, providing a sling shot 95+ mph ride in 4th gear down the hill and into the braking area for the final turn. At this point we were right on the back wheel of the B31, with Joe having eked out a safe gap on his pursuers. I only know one quick way through turn 7 – the late apex, early on the gas exit that I had used to get in front of the B31 during one of the races in round 2. But the bugger had learned to cover my line, so when I tried to pull up the inside of him on the exit, he was right there, limiting my space. But despite this, Li’l Speedy’s excellent 3rd gear torque was more than a match for the B31, so we carried better momentum onto the straight, inching alongside and then almost level. As the mighty long stroke engine revved freely in 3rd to somewhere just beyond my normal 7000 rpm “heat of battle” limit, we crossed the finish line. Sadly we were two tenths down on the B31, with a further 1.4 seconds to the winning ES2. But still, a great race and a lot of fun.
On analyzing lap times after this race I concluded that we needed to reduce our lap times by 1 second or so in order to be able to compete with this pair, without riding the wheels off it and/or overstressing the engine. In discussion with Welshman Dai Gibbison, he had mentioned the surprising improvement in quarter mile sprint times he discovered when he converted his iron MSS sprinter to belt primary drive. We thought this could be a step in the right direction – improve performance by putting more of the current power to the rear wheel. So Dai put me in touch with English gentleman John Watson, who obliged in manufacturing a belt primary drive conversion for Li’l Speedy. It was while measuring some of the crankcase offsets for John that I discovered a problem - the crankshaft clicked when I grabbed the engine sprocket and gave it a tug. There shouldn’t be end float in the crank, I thought, I’d better investigate further.
Next evening, the problem was revealed – the timing side main bearing had started to turn in the case, eating its way outwards in the process. This was the roller bearing that replaced the original ball bearing that had failed disastrously early in season ’04.
At this point I decided to take a new roller bearing off the shelf (I had been saving two of them for another race engine project) and with the help of Jack Watson, built up the OD of the cup to provide an interference fit. However before reassembly could begin in earnest, a particularly demanding 8 month period on the business front began, eating severely into my spare time. This put paid to any thoughts of being back on the track in 2006. Then at the start of season 2007, with a lengthy mid year business trip come holiday planned, I decided to sit out the year, and get Li’l Speedy back into action during 2008. In November next year, WA is again hosting the National championships so having Li’l Speedy well sorted and reliable by then is a must.
The To Do list includes fitting an MSS gearbox with the new belt drive and clutch, pensioning off the 68 year old conrod in favour of a new Carrillo, fitting a smaller and less fragile at the seams fuel tank. Oh yes, and maybe some zinc plating on the nuts and bolts and a bit more paint! As usual, the cosmetics are near the bottom of my list.
1 day ago
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