[atvracer1971]

:blink:I have a 2001 400ex, rebuilt the engine 5 months ago, 426cc, stage 2 hot cam etc. Anyways it was running great, no problems then all of a sudden a few weeks ago i lost power at 3/4 throttle. I changed the main jet(smaller) cleaned the carb and still the same problem. Possible ignition control module problem?? IS there any way to check it? OHMS etc? A new one is $100. Also i checked the ignition coil, it had 18.5k ohms and I heated it up and it went up to 20.5k ohms. My honda manual does not tell you any values to check.

Any help can be appreciated!! Getting tired of missing all this great riding weather. Still waiting for the new 450r to come out., I heard maybe 2012

 

[69quadracer]

Welcome to the forums! havn't had much dealings with the 400ex but some of the other guys here have them and will be able to point you in the right direction.

 

[TRX2fiveO]

Welcome to the forums. I don't think it's an electrical issue. You may want to pull the slide assembly out and check for scoring and check to make sure the clip on the needle didn't by chance break. Also check the choke lever they have a pretty good track record on these carbs of getting weak where it mounts to the carb causing them to actuall close to the first click with vibration, I had this issue with my carb.

 

[Helmut]

Welcome to the forums.

 

[atvracer1971]

Thanks, I will check the slide, I think that is the only thing I did not check!!

 

[tomgodd]

Welcome to the Family!