News 2003

31st December

OCTOBER came and went with a solo test for me, as Dominic is now at Birmingham University on his M.Physics course. With non of the other members of the team attending due to illness things were a bit fraught. With so much more power, 2nd gear burnouts are a doddle now and I made one hard launch where 'The Fang' carried it's front wheel through first gear. However fuel starvation problems in the higher gears forced the run to be aborted. With the lunch break ahead and work piling up at Turnertech I had to call it a day.

SINCE then the Turnertech works has been flat out and I didn't have time to look at the bike until Christmas Eve. During a frantic day in the workshop I finished the new clutch cover, removed the Shorrocks and balanced the new Eaton in position to plan out the mountings. Unfortunately the rest of the 'holiday' will be spent producing a prototype for delivery on 7th January, so The Fang will have to wait for a lull in production.

2003 saw us take significant steps forward, and despite the lack of results we have learnt a great deal and plans for 2004 are more focussed. A new sponsor has offered us unlimited dyno time and discussions with another potential sponsor could result in use of a van - 2004 is looking good!

Happy New Year folks.

17th August: Latest Test

EQUIPPED with new electronic ignition and first kick starting we headed of to Devon and the NSA sprint at Smeatharpe hoping for a full power run by the end of the day.
As nothing fell off on our last outing, 18 year old Dominic was back in the saddle for the first time in 18 months.
The bike started easily and a tentative run around the car park showed the misfire had gone. Judging from the clouds of black smoke it was running rich but Dom went for his first run and this was confirmed, it just wouldn't rev and was very woolly.
The H1F SU is a blessing when it comes to tuning; just turn an external screw to adjust the main jet. Dom performed an impressive burnout whilst I made adjustments and everything was fine with the relief valve popping at 15 psi and 6000rpm.

OK off to the start for a proper squirt. With a terrific aggressive hard edged bark, The Fang left the line like a bullet..........(you just know something is going to go wrong), sadly when Dom changed into 2nd the power faded badly, what now?
Back in the pits the bike ran fine with no odd noises so we tried another run, this time the engine was very flat and wouldn't take any throttle.
Back to the pits again for another beard tugging session; fellow racers offered pearls of wisdom but nothing seemed to add up. Then Dom commented that he didn't remember seeing any boost on the gauge, stripping off the belt guard gave the answer: the blower pulley and shaft were turning but nothing could be heard inside other than a very faint scraping. Oh well back on the trailer and a slow journey home avoiding cows on the road, a traction engine and some coffin dodger who insisted on driving at 25mph for miles!

ON Monday evening we eagerly stripped the blower of the bike and carefully removed the drive side cover; sighs of relief, the drive shaft had sheared clean off the rotor drive flange leaving the fragile vanes and rotor undamaged. For some reason, Shorrocks machined the bearing seat without a radius and I guess this is where the fracture began. Fortunately we have a spare as I don't really have the time to carve a new one from solid. Hopefully we'll be at the season closing test and tune at SCR.

Update 26th August

Careful examination of the broken bits showed signs of rust in the fracture, so failure was inevitable sooner or later.
The spare has been fitted and engine fired up, normal service now resumed and next stop a test and tune.

Who doesn't enjoy this part of the ritual?

The perfect launch, back wheel spinning slightly and the front tyre skipping across the, err track (click on the image to see a larger version - apparently the track is used by NASA for testing Martian rovers), then......

So that's why the boost dissapeared!

6th July

TESTING at last, with me riding, as there was so much new stuff I've made. In the event this was not a good idea, but I'll leave my son Dominic to give the details:

EARLY Sunday morning ‘The Fang’ was conveyed to the NSA sprint at Weston Zoyland near Bridgewater, for the first outing with the supercharger.
We hoped to get lots of runs in which would be valuable for setting the bike up. The bike passed scrutineering fine and so did the leathers, gloves and boots, but the helmet failed; doooh! wrong ACU sticker (I new we should have brought my helmet). This is where Dave and Jane Glover stepped in; Dave was already sharing his helmet with his brother, yet generously let my Dad use it too! Of course this did lead to a lot of running around and 'hot swapping' of the helmet, but If it wasn’t for Dave ‘The Fang’ would have never turned a wheel down the track, so many thanks.

First attempts to start the bike left my Dad with a larger right leg due to the copious amounts of kicking. We think the long plenum chamber contributes, but this was silly, it would just pop and bang occasionally. We took the points cover off for a quick check and then gave it one more kick: the bike started and carried on running! So Dad set the initial adjustments on the SU carb, and got the revs down to a nice tick over. I was amazed as the bike started hunting and the handlebars gently oscillated in unison. It was the sort of hunting that you would get from the old top methanol cars with the roots type blowers.
As we had no idea what boost we would get, we are running on C-16 which we acquired from Rachel Pattison (many thanks Rat). A blip of the throttle set off a nearby car alarm, people began to take an interest! What will it sound like running on methanol? In the warm up we were getting around 10 psi which explained the louder and much more aggressive sounding Fang.

The first run Dad just drives off the line, so we can check if everything is OK, but then the bike went straight into a really bad intermittent misfire. When the bike did start to pull, which would happen after he had rolled of the throttle and then started to open it again, it would pull a lot harder then normal so Dad guessed it was running rich. A few runs later and it became clear the mixture was OK but we still have the same problem with the misfire, but even worse with the engine cutting out completely and then suddenly bursting into life and nearly wrenching Dad’s arms out of the sockets. He saw over 15 psi boost at only 6000rpm and the power is definitely there. After 3 runs the sparks finally disappeared and it appears that we should scrap the points for electronic ignition, the 500T electronics have plagued us with problems from the start.

‘The Fang’ attracted lots of interest and photographers, and we are really happy; the bike sounds and looks great and we know that we can cure the problems. Best of all the blower belt didn’t break, all the new bits were fine and Dad’s worst fears regarding the 180° crank didn’t cause a problem.
Our new Eaton blower has just arrived from CCSE competitor John Sleath and things are looking good. I can’t wait to get back out at Shakespeare County Raceway.

Click here for a small MP3 (76Kb) of 1/4 of a very small Top Methanol car.

21st June

DESPITE working a near 7 day week at Turnertech we are still on target for testing at Weston Zoyland early next month. My new underslung billet kill switch is fitted, leaking supercharger manifold fixed and this week 2 gallons of racing petrol organised. With the supercharger fitted, the effective compression ratio could be as high as 14:1 hence the need for 118 octane fuel.
Just the myriad little jobs to do now such as today; making a polished alloy OFF label for the fuel valve, moving the seat back a couple of inches, Helicoiling a stripped thread, attaching the oil catch can and modifying the choke mechanism on the SU carb for easier operation.

1st June

TURNERTECH is very busy again so work on the bike has lagged a bit, but is still on schedule for our planned testing session. Helping to install a ZX12R engine in a kit car yielded the Kawasaki exhaust downpipes as a bonus. With the aid of a bandsaw and MIG welder, these were swiftly converted into a shiny new stainless exhaust for 'The Fang'.
Our fan may know that the bike uses a Honda CB250RS front end and the brake has been a problem for some time as it weighs a ton and the master cylinder takes up far to much room on the handlebars. These have now been replaced with super lightweight items from a Kawasaki KMX200 and another shiny alloy bracket made to fit the caliper.

JUST to test the new exhaust you understand, we had to start the bike again. This time I let the bike warm up much more and got the engine close to tickover. To our great delight the engine started 'hunting' very slowly like a Top Methanol car but with most of its cylinders missing! It was a couple of hours before I stopped grinning, perhaps I should get out more!

I'M working on a custom aluminium lanyard kill switch at the moment to replace the cheapo plastic item we have. Checking the latter with a meter showed the contacts were opening slightly with a gentle tug on the lanyard.
MORE pictures soon.

16th May

SINCE the last report I invested in a metre of Samco blue silicon hose for the supercharger manifold and a boost gauge. As a result I now have loads of 38mm straight hose available at the next SCR meeting. Various odd jobs were attended to, including a leaking weld on the manifold and constructing a proper wiring loom - no more insulating tape! One problem I have is supercharger lubrication, as the metering pin was missing. I guessed at a diameter for a gravity feed and obviously was way too small as an egg cup full of oil disappeared on the first start up, so a larger one was fitted (when I arrive at the correct size this will be posted in the Shorrocks section). The belt guard was installed, mods made to my newly designed clutch operating mechanism to clear the huge gearbox sprocket, and breather catch tank fitted using some surplus red hose from the new washing machine!

YESTERDAY the whole team gathered around outside the garage, each assigned jobs such as watching the belt, boost gauge, looking out for annoyed neighbors etc. I had finally figured out how to operate the SU choke, and so after a few kicks to distribute the oil, ignition on and a few more kicks before wooombah! Whilst the engine warmed up at 2000 rpm negative boost was noted as expected, in fact the Samco hose was fairly collapsed ooer! A blip of the throttle sorted that out as the gauge went above 0psi, OK no leaks - one last bigger blip to about 4000 and triumph as the gauge swept up to 5psi. I cut the engine and looked around to see huge beaming grins, I suspect mine was the biggest. Better still nothing had gone bang or fallen off and the belt was still in one piece.

TRACK testing soon. I can't wait!

5th May

THIS photo was taken 3 weeks ago. Since then much burning of midnight oil brought us to a significant point this weekend.
Whilst Dominic and his mate were off enjoying themselves at the Excitement Nationals, I rigging up a rough wiring loom and refitted the exhaust aided by crew chief and number 1 daughter Bryony. Saturday was a frustrating day when first the SU float chamber cover 'O' ring started leaking. Then despite a healthy spark the damn thing refused to even make a feeble attempt at firing. Aaagh, time to take the dog for a walk!

SUNDAY dawned with an early start and a more rational approach. After spending nearly 2 hours examining the ignition system closely I made an interesting discovery, one pair of the brand new set of CB points had a mystery intermittent dead short. Selecting another set of points from the previous racing engine produced the same effect on the other cylinder, no wonder it never ran properly!
Combining bits of both sets produced a consistent spark on both cylinders. OK, petrol on ignition on, kick.....bloody hell fire! Good job I was wearing my ear defenders as the engine burst into a deafening fast tickover. A tentative blip of the throttle nearly took the garage roof off, OK that's an exaggeration but I was a bit over excited.

THERE is still a fair bit to do and we won't make my scheduled track test next weekend but things are looking up.

20th April

DUE to pressure of work at Turnertech, progress on The Fang ground to a complete halt in November. Even the Christmas holiday failed to bring a respite, so in order to get to the track some time in 2003 a change of plan was required.

WORK on the new bike has been abandoned and the supercharger is now mounted behind the engine in the 2001 bike. Not the ideal solution as the C of G is now much further back and combined with the short wheelbase should provide some wheelie good fun.
FORTUNATELY most of the parts made for the aborted chassis went straight on the old bike and we hope to have a test fire up in about 3 weeks, with a view to track tests at a sprint shortly after. Photos soon.