Saturday, 27 December 2008

2009 Full Specification

Over the last few months I've had quite a few messages and requests for more information on the specifications of the race scooter.

So i thought it sensible to do a full listing!

Will save a lot of answering questions!

So........... here goes.................
  • Frame - Indian GP150
  • Forks - GP200. Rebuilt with Taffspeed progressive springs, stainless steel one-off spring bushes, fork links modified to take brass bushes in place of nylon, Stainless pivot bolts.
  • Front Brake - ScootRS external hydraulic disc, stainless hose, Gilera runner master cylinder
  • Bodywork - GP200, fibreglass front mudguard, fibreglass side panels, strengthened floorboards.
  • Handlebars - SX200 (lower than GP), perfectly matched rods internally, perfectly free throttle operation.
  • Ignition - BGM stator plate, custom lightened Vespa PK flywheel, plastic cooling fan. Ducati Coil, Agusto advance/retard unit.
  • Barrel - Rapido Race 200. Tuning by Chalky White - Replay Scooters. Full Race Tune. 31.5HP
  • Piston - Suzuki
  • Cylinder Head - Readspeed Centre Plug - Nippon Denso Spark Plug - NGK rubber HT cap
  • Crankshaft - Chalky White special. GP split and rebuilt with Jap con rod. Tig welded
  • Carburettor - Mikuni TMX35
  • Crankcase - Italian SX200 (!)
  • Gearbox - Li150 Pacemaker
  • Clutch - 6 plate - Surflex clutch plates
  • Chaincase cover - Li 150 - internal modifications to take 6 plate clutch
  • Gearing - adjusted to circuit, using 46 or 47T rear sprockets, 15. 16, 17 ,18 fronts.
  • Chain adjustment - Nylon top adjuster only
  • Exhaust - Hand made one off full race exhaust , carbon mufller , Malc Anderson / MSC design specification, fully rubber mounted.
  • Rear Suspension - Hagon adjustable
  • Rear Brake - one off rear set brake, GP performance brake shoes.
  • Tyres - Dry - Dunlop TT92
  • Tyres - Wet - Sava Monsun wets
  • Seat Unit - Fibre glass single seat
  • Cables - Nylon lined, gear tie rod drilled and m6 retaining nut.

Friday, 26 December 2008

2009 Engine Upgrades - Dyno Results

Since the racing at Joigny in France, the engine from the race bike has been with Chalky White at Replay Scooters in Rothwell.

Chalky originally built the engine for himself to race, but never really got around to it! Chalky spoke to me at Cadwell, and was delighted that his engine had finally made it onto the track!

You may remember that at the final BSSO race at Cadwell I had what proved to be a 'phantom' twisted crank... i.e. it wasn't actually twisted despite giving the symptoms of a twisted crank! I had managed to run at Cadwell and at Joigny by using Ralph Remnant's (SRP Tuning) spare Motoplat ignition set up.

So after France, Chalky offered very kindly to check over the motor, and try to get to the bottom of the ignition problem. We also agreed that he would do some more work on the barrel to provide some more power for 2009. When he had originally tuned the engine, he wanted something with a reasonable spread of power and a rideable delivery. The engine had proved to be great for my return to the race track after 13 years away...... enough power to scare me, but not enough to spit me off...... but above all (except for the ignition problem) reliable!

I had been giving 2009 a lot of thought after Joigny. I was enjoying very much the thrill and adrenalin fix of being on a race track, but realisitically at 45 and such a long time away, I ain't going to be challenging Stuart Day and Charlie Edmonds any time soon!

So I decided that some economical power improvements to the motor, and as much track time as possible using test days at Mallory and the like, would be the best way to go!

So.......... fast forward.......... Chalky has done an absolutely superb job on the engine. Improvements are;

Crankshaft - New crankshaft has been built and fitted. A good quality GP crank was split by Chalky and rebuilt with a longer Japanese con rod. This new crank will be able to handle the extra power Chalky was working on!

Barrel - The existing Rapido barrel was reworked. Transfers were enlarged through their whole length. Exhaust port considerably altered and raised to give 192 degrees of exhaust. The inlet was enlarged and smoothed to improve the matching of the barrel to the inlet manifold.

Ignition - The old ignition stator plate has been totally replaced with a new one. A BGM stator plate was used to provide the sparks! The previous flywheel (modified Vespa PK with plastic fan) was cleaned up and skimmed to tidy up the internal damage.

Agusto 8000 - Chalky's superb Agusto advance / retard box of tricks has been added to improve power and pickup.

Exhaust - A few cracks were found in the exhaust system, so these have been welded and fixed. New exhaust rubber mounts.

So.... after Chalky had done all the above changes, I took my frame down on Christmas Eve and we re-fitted the engine, and put the bike on the dyno for a couple of 3rd gear power runs to see the improvement. At the start of 2008 the engine had been setup with a Mikuni 35mm carb on the Chiselspeed dyno and had produced 23.96 HP so both of us were keen to see the improvements. In my mind I was hoping for 27-28 HP.

The engine started easily when we bumped it up outside (to please Chalky's neighbours!) then it was up the ramp and through the workshop keeping the engine running whilst we strapped down on the dyno. We had checked the Agusto advance / retard system with a strobe, so we were good to go!

The first run..... just under 31HP............. big smiles all round.....

The second run ..... 31.5HP!!!!!!!!! ..........

Heres the dyno chart>> ( click Chart for full view )

Chalky said that as he accelerated the engine felt really smooth - like a very powerful road bike...... great spread of power...... should be superb out of bends.

The engine is producing over 30HP across a pretty broad rev range. I have always preferred engines with this type of power delivery so I am well pleased with the results. Torque is pretty good as well with maximum of 20.7 Nm at 7700 revs (peak power was at 8100 revs).

Theres a little work to do on jetting, with something wild occuring between 6 and 7,000 revs, but it's safe so we will play around with jetting at a later date.

So..... were we pleased? You bet!!!!!!!!!!!

Unfortunately due to external factors I was not able to go play at Mallory Park Plum Pudding on Boxing Day, but hopefully in February / March I will be able to start testing at Mallory practice days..... I reckon the first race meeting will be a great feeling !

A really big Thanks to Chalky White at Replay for all his help and great work on the engine. Very much appreciated!

Chalky's Contact details are;

Replay Scooters
2 The Avenue
NN14 6EY
Tel (01536) 418893

Saturday, 13 December 2008

December Update

Well people............... not a great deal happening with regard to the bike at the moment....... but here's an update.

I had decided originally to build a new motor for next year, but have you heard............. there's a credit crunch!!!!!!! I also decided that in reality....... money would be better spent on track time re-learning to ride fast rather than on some mega motor that I can't ride!

Chalky White of Replay Scooters in Rothwell had originally built my engine for himself, but never really made it out onto the track. Chalky introduced himself at Cadwell, and very kindly offered to relook at the engine and do some more work on it to help me out.

So after the racing in France, I dropped the engine out and took it to Chalky. The plan is to do some interim work on the barrel to produce some more power, and of course sort out the knackered ignition system! (Thanks again to Ralph at SRP for the loan of the Motoplat) and then in the spring do some further developments for 2009 with a possible change of exhaust system, and also going to direct scoop cooling. With Chalky's help this can be achieved hopefully with minimal outlay, leaving money from my small racing fund to use for some track days and tests, which in reality will probably be worth more time than a bonkers engine!

So...... what else has been happening? Well over a few evenings, rather than waste time sitting in front of the TV, I used it productively to edit a video which is a spoof of Hitler's reaction to Tony O'Brien's mega small frame Vespa. Its been well accepted and already doing the rounds of scooter forums, and quickly racked up 1,000 views! For those that don't know, there's a number of alternative versions of this video clip from the German subtitle film 'Downfall'. The original film is apparently very good, but somehow people have produced umpteen spoofs of this video clip with alternative subtitles, with everything from Churchill stealing his Big Macs, to him having problems with Microsoft Vista!

So I can't claim originality for the idea, but it was great fun, and actually harder than it looked trying to make things fit, and in places even match the sound of the German words.


So................ what else is happening? Well, the BSSO AGM is only a month away so it will be interesting to see if anyone is going to propose anything radical or controversial! With all the development going on in the road scene, with some VERY well engineered clutches, barrels and even gearboxes coming along, it would seem the right time to complete a well overdue review of the BSSO Racing regulations and specifications. The published ones are desperately in need of review and it would be great to simplify them and help out the many newcomers showing interest in racing. At the moment it's looking like we will have some full grids in 2009...... economy permitting!

We don't have a calendar of events finalised yet but I know we have the offer from the VMCC to race with them again. They are really a great bunch, and they and the spectators make us very welcome and enjoy the spectacle of howling scooters blasting around!

My good friend Dave Crampton will be a new entry next year on another bright green machine! This one will be a Gilera Runner, built to compete in Group 6. Dave's from an engineering background and has a number of subtle, but very trick additions and modifications to his Runner. It will be interesting to see how he goes - but I have a sneaking suspicion he ain't going to be at the back (no pressure!)

If I don't update before Christmas........ Peace and Love....... Happy Christmas (war is over!)