I know this has been asked before but I'm new to the forums and generally new to sport quads. I bought a 400ex and the top end needs rebuilt. I got some advice from my friends who have been around these machines and have done rebuilds in the past. I ordered and a 416 top end, stage two hotcam, wiseco 10:1 piston kit, and commetic gasket set. The bike has a full big gun exhaust. Im just not sure on the jetting. Its already jetted from the previous 426 with stock cam but ran a little rich. Any suggestions? Also any other mod ideas? It has a k&n air filter and open top airbox.

 

Also other work I have done to it: new battery, new starter clutch, new solenoid, new starter brush wires, nerfbars, extended rear Axel, aftermarket handle bar. I was thinking maybe 450r carb and shocks. I trail ride and ride in pastures, minimum maintenance roads and the river.