Motorcycle Repair: honda 900f, valve stem seals, johannesburg south africa

Question
Hi Jan. I hope u can help. I know u only only work on cbx1000. I ran a bearing and stripped the motor and redone complete motor. I also changed valve stem seals. I have reshimmed cam valves. My problem is it won't start. It just backfires and only exhaust pipe 3 gets hot. I have even changed the spark units to see if it will help. I'm at a total loss. I would appreciate any help. No one in johannesburg south africa can help. Thank u carl

Answer
Hi Carl,

Is there a chance that you got the valve timing wrong?  There are marks on the cam and the crank and they have to be aligned perfectly if the engine is to run.  Did you do a compression test to see if all is well?  You need compression, fuel and a well-timed spark for it to run... Establish what is missing, bearing in mind this is a wasted spark engine so 180 degree difference on the cam makes no difference to the enging running.