Originally Posted by texasadv
I just finished rebuilding a '71 suzuki TS125. Bore size was increased to 57.5mm and a wiseco piston installed. A stock suzuki head gasket "G" was used as well. Compression test shows around 110psi. I'm assuming thats good.
So when I tried to start it I could sometimes get the bike to turn over briefly but only with full throttle. It would die almost immediately. I could kick it all day long and not make any progress; it would start then die. I checked timing and it seems fine. I get spark. I must also mention that I dont have the airbox etc so I'm running a pod filter. I have cleaned the carb several times and feel pretty solid that it's clean. I tried a variety of pilot jet sizes from 25 (stock) to 32.5 and no difference. The plug seemed to be getting gas. But again, unless full throttle was applied there was no way it would ever start.
So is it a carb problem?
Does my stock cylinder head need to be reprofiled from 56mm to 57.5mm to match the cylinder?
Will the gasket I'm trying to use work or should it be enlarged?
Though it shows 110psi I am able to easily turn it over by hand via the flywheel. Is that ok?
I'm at a loss of how to address this problem.
Thanks for any help!
Check fuel flow at the petcock and consider non ethanol fuel. Sounds like a carb/fuel issue.