Hey guys, my 03 z400 has been running very very bad the last few times ive had it out on the trails. Ive always taken great care of the bike maintenance wise but rode this bike hard...all the time. Ive noticed its been running very hot lately, and the fans are always running on it. Under deceleration I feel alot of vibration between my legs, im pretty sure its in rhythm with the piston and believe its "piston slap". The motor has been louder then ever, it barely idles anymore and when it does it sounds like I can almost hear metal on metal . The carb has been off and its been cleaned not to long ago.

Im going to bring the bike to the car dealership I work at and am going to start off with a compression test. Roughly what should the compression be, and hopefully that should give me a diagnosis on the bike. If it needs a rebuild Im going to have alot of questions, but I want to be able to diagnose the problem first.

-Gary

 

142 and hold the throttle wide open.