New to the forum but been reading for days. Anyway upgraded my kids 2004 raptor 50 with the following. Procom 80 CDI, did the clutch *****, put a completely new 80 carburetor with 80 internals, took out spark in exhaust and put a K&N filter along with a new spark plug and trimmed the throttle bracket.

Problems I’m having after installing everything is bike sputtering at mid to high range RPM and constantly fouling the plug (black) any suggestions? Do you think I need a new coil or maybe even have to adjust the valves in the head? Could that be causing the sputtering which is the reason why my plug is black and fouling? If I install a new plug it will be black within 30 minutes while trying to tune the bike.... any help appreciated thanks also for some reason I can’t find that raptor80racing website..... did they shut down?

Also since I’m here asking why not throw it out there, if I purchased a 80 cylinder head kit will it work without having to crack open the case? Is the stroke the same on the 50/80 and just a bigger cylinder head/piston etc? Thanks I’m advance

 

This is a 4 stroke, correct?

 

yes 4 stroke.