2 quick questions here. 1st, looking at buying a bike, Seller says its is a 80" evo (which the motor #s confirm), but says that it has larger heads, pistons, etc. on it, I believe he said 96". Is this possible, and if so how can I tell without pulling the heads. I see no #s or names on heads or cyl. except for casting #s.
2nd its running a super E carb, starts fine and idles fine once warm. Runs good unless you try to give it fast throttle, or chop the throttle, then it stumbles. It revs up ok when you rev it slowly, but when you do it fast it kinda just sits there and doesnt rev up. No major backfiring I can hear... I'm new to evos so any help is appreciated.

 

rule of thumb...if you rev it and your tach drops really slow then its lean, it your tach drops below set rpm then raises back up to idle its rich...you can almost set the carb mixture to that then read plugs...put in clena set..run bike to full temp then kill and read plugs...dont rev over 2000 while doing it

 

It sounds like you have a flat spot coming off idle and that the accelerator pump might not be working. The easiest way to do this is with the engine not running. Pull off the air filter cover and quickly open the throttle and watch for a squirt of fuel into the intake manifold. No squirt means the accelerator pump is not working. The diaphram could be bad or even the smallest particle of dirt in the fuel bowl can plug the accelerator pump orfice. As far as identifying the cylinders or pistons as being bigger, ask him for the receipts. I dont think there is any way to just eyeball the jugs to determine if they are bigger internally..................BG

 

Holy crap I just looked at the date of the original post and it was almost a month ago. Sorry guy no one got back to you before today.................BG