I have a kitted FZ-50 (w/ expansion chamber) that even when it wasn't kitted has never hit even stock speeds. Definitely no air leak, and tested to confirm good compression.
Advancing the timing gives only slight improvements in speed. It seems that my CDI is retarding my engine top speeds. Exchanged my stock CDI with a CDI from Nate Bandit's FA-50 which is known to rip...yet STILL no improvements in top speed.
Anyone have experience with these sorts of issues and know of any other CDI's I could run on this bike?