400ex 1/2 throttle problem

[matholland]

I had bought an 02 400ex that was blown up. due to no oil. I got it bored to a 416 and got it all back together. I had a guy do the work to the motor for me. I got it going now and it runs great, but I do have a problem. If your riding it and you hit over 1/2 throttle it wants to die (like a limiter) it will stay dead until you let go of the throttle past a certain point and it workk go again. It also puts presure on the throttle like outwards. It has to be some sort of limiter, but not sure where to look.

[gt400ex]

Did you rejet for the 416?

[matholland]

didn't need too..sparkplug says its fine...its not a jetting issue i wouldn't think...i mean whenever you hit that point theres likes a clicking and it pushes back against your thumb, it has to be a limiter or something.

[gt400ex]

Might pull the cover off the thumb throttle, check the side of the carb. Could even be a bad cable.

[400exOverride]

sounds like the coke is on. on my 05 when chokes on it kicks back on the throttle.

[bigbad400]

sounds like a bad cable or somethings binding, not good. i would look into your whole throttle assembly and see cuz as far as i know there is no actual limiter like that on the 400ex. actually the blaster is the only one i remember with the real throttle limiter. what a waste of time that is.:huh

[mcgrath]

Have you adjusted your valves lately? It sounds like its poping back through your intake. When you did the rebuild did you do the valve seats? check the valves to make sure they seat properly? If its comming back through the intake it has to be from valves not seating properly, timing off, or backfire due to jetting. If your jetting is good Id check the valve clearance, and check to make sure the timing isnt off by a tooth. Not sure, but a good place to start.