[mktshirt]

Hello all! When I finished cleaning the carb on my 2000 ex 400, I noticed a small o ring (4-5mm) on the ground. The bike runs but won't idle and I can't seem to find where the o ring came from. Any help would be greatly appreciated!

 

[retro]

Here ya go, the factory service manual for your 400ex.

Welcome to the forums!

 

[Goober]

If the carb is similar to. Trx350 might be the oring that joins the bowl to the throttle linkage cavity drain

No forget that too big