my bad: Godet 500 Flash claims 60hp.I've not heard of a Godet 600 single........Ours are all 500 cc, but 2 different engine bore/stroke combinations used........Stock French engine uses a 92 x 77.2 mm.......whereas our modified engine uses a 86 x 86 bore/stroke.......This second engine was re engineered by Peter Molloy here in Australia a few years ago.......he was a specialized engine builder who came up with this engine spec combo........Both these engines use a one piece all steel crank with 2 piece shell bearing con-rod.......These engines will rev to 8000 rpm plus, the 92 bore engine even higher......of course they all use a high pressure oil pump and the engine casing has provision for the WR Yamaha type pump.......My engine, i have set the rev limit to 7200 on the limiter but seldom take it past 6200 on the track......It has a huge amount of torque, so simply reving it higher is not really necessary...... i doubt any of the French engines has gone near 60 HP.......The design just simply is not that high a spec......Its power comes from big revs and massive duration cam timing.......There is more that can be done, its just time and money...... The French engine is great, but the top end and cam design is too old school i feel.
those BxS combos come near the ABSAF (BSA Goldstar D34) competition engine config, they push out well over 50+hp below 7000rpm.
uses metric bearings and vernier cams but 1:1 interchangeable parts with the original BSA of the '50s.
their full race spec engine with 12.6:1 comp ratio and some goodies makes 7400rpm redline and ample torque to stay ahead of the pack.
coming back to Vincent: I'd've thought there were larger valves for these engines and room for improved air flow in the porting to keep it going with RON98E5 petrol (instead of blown and/or ethanol)?
for my Bullet I've been studying JAWA 2V engines, these do in the region of 60-80hp and upto 13000rpm for bob's sake!! cannot be compared to these English lumps, but still, gives perspective on what can be achieved with modern tech fitted to antiquated (yet advanced in those days) design. speaking of, the Godet 500 Flash is very near the JAWA engine BxS...
have yet to compare a stock Vincent piston with that of a RE 500 (apart from the gudgeon pin dia) perhaps these can fit in a Vin (piston prices in favour of the RE)?
apologies in hijacking this thread.
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