hi there. my neighbours 50cc speedfight (v reg)gave up on his way home after he hit a bump ive checked it over it still sparks but its like the timing has moved(if this is possible)it nearly starts then backfires. Any ideas anyone. Cheers John...

john mclauchlan, March 2010

yeah lol.

adam bike doctor, March 2010

thanks adam. i didnt think the timing would be adjustable.. oh well time to tell him the good news.. cheers

john mclauchlan, March 2010

it can only move if the woodruff key shears on the crankshaft and the magneto will then not be in the correct place.saying that i would say that it has ahd a seizurea dn is low on compression as a chuffing noise from the exhaust can be due to the fuel air mix burning in the exhaust when it fires and if its piston is damaged the lack of compression will stop the fuel burning like it should.i take it you have tried a new plug?ngk br7hs is the one you want.

adam bike doctor, March 2010