having problems with my 77 kz650.. recently when I start my bike.. start riding, between 3-4 rpm bike starts to spit & pop.. but after bout twenty min of riding it starts to smooth out... just curious if any body has any ideas...
If the bike ran good and then started to act up like that I would check for vacume leaks around the intake manifolds. Spray carb cleaner around the manifolds as the bike is running and if the RPM's go up then you have a vacume leak.
