Dave Jones

im just doing this at the minute and seem to have similler problems, ive got a 2002 bike which has dropped the exhaust valve, so ive got a M reg 1995 engine which i have seen running fine and put that in, i have swapped the left hand casing and flywheel, so all the wiring matches up with the cdi etc, problem i have now is im getting a spark, got fuel, checked valve settings and timing and its all coming back fine, im slowly at a loss, ive got some spares so iv swaped, the carb, the coil, plug, cdi, etc to no avail. still the same issue, my next logic would be to say that the ignition timing could be out? can anyone help me on this? Cheers Dave