monty_jon Posted May 17, 2011 Report Share Posted May 17, 2011 (edited) BSA On ebay: BSA C15 It seems a very nice bike, but if Im not mistaken that seems to be a B25 with a B25 Frame (pre oil in frame) The B25 was made 1968 onwards What would happen if you tried to enter this bike in a Pre65 trial? Edited May 17, 2011 by Monty_Jon Quote Link to comment Share on other sites More sharing options...
woody Posted May 17, 2011 Report Share Posted May 17, 2011 Most are Pre70 classes so it wouldn't matter It's only Scotland it couldn't be ridden, Yorkshire and Red Rose classic would probably insist it go in the specials class Quote Link to comment Share on other sites More sharing options...
monty_jon Posted May 17, 2011 Author Report Share Posted May 17, 2011 Most are Pre70 classes so it wouldn't matter It's only Scotland it couldn't be ridden, Yorkshire and Red Rose classic would probably insist it go in the specials class That Quote Link to comment Share on other sites More sharing options...
02-apr Posted May 17, 2011 Report Share Posted May 17, 2011 BSA On ebay: BSA C15 It seems a very nice bike, but if I Quote Link to comment Share on other sites More sharing options...
woody Posted May 17, 2011 Report Share Posted May 17, 2011 The C15 is a better engine for trials as it needs less work to put into trials trim. A standard road engine is fine as it is and just needs the gearing lowered. B25 has a big valve head, bigger inlet tract and much lighter crank assembly. They were designed as a 'revver' rather than a 'plonker' type motor and have better top end power whereas the C15 produces better torque low down. The light weight of the B25 crank makes them easy to stall so you need to use the clutch more. The C15 has a really heavy crank assembly and will chug to a virtual standstill, clutch out. The B25 is more prone to spit stalling due to the more racy head design. This isn't to say they won't make a decent trials motor as they will, but more work is needed over a C15. The frame on the ebay bike could well be a genuine Pre65 as that design with the 'V' shaped subframe was available in 1964, so the Pre65 label in the title isn't really inaccurate. The engine isn't Pre65 but what is anymore, Pre65 is just a generic label now that has stuck - Pre70 is more accurate these days as most trials run Pre70 British as a class, not Pre65, apart from the 3 mentioned above. Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted May 17, 2011 Report Share Posted May 17, 2011 BSA On ebay: BSA C15 It seems a very nice bike, but if I Quote Link to comment Share on other sites More sharing options...
bashplate Posted May 18, 2011 Report Share Posted May 18, 2011 (edited) very nice looking bike . i can't beleive someone would go to all that trouble and not do what ever the motor needed to make it a peach. it's obviously had work, as it says it's 280cc (could be a triumph bonnie piston with shortened skirt:- 71mm bore x 70mm stroke = 277cc)and it's got a micky rooney carb. proberbly got a heavy crank and suitable cam in it too. Edited May 18, 2011 by bashplate Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted May 18, 2011 Report Share Posted May 18, 2011 very nice looking bike . i can't beleive someone would go to all that trouble and not do what ever the motor needed to make it a peach. it's obviously had work, as it says it's 280cc (could be a triumph bonnie piston with shortened skirt:- 71mm bore x 70mm stroke = 277cc)and it's got a micky rooney carb. proberbly got a heavy crank and suitable cam in it too. Mickuni carb would probably cause palpetations at most Classic and Pre65 events. Best to check if acceptable with the organising club first. Just trying to be helpful Quote Link to comment Share on other sites More sharing options...
jonflower Posted September 30, 2011 Report Share Posted September 30, 2011 This is one of mine and my dads bikes now, its a beautiful looking bike and trials really well. One of the nicest bikes I've competed on I think Quote Link to comment Share on other sites More sharing options...
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