wr 400 keeps stopping

I have a 00 model wr 400, The problem is that when it is ideling and you go to give it full throtle it dies and it also does it when you go to give it s%#t around a burm it just stops also.

Can someone please help as it is very annoying.

Firstly...

If it was working fine before...

- clean your carb with contact/carb cleaner and compressed air. First make sure ALL the o rings etc (esp the ones left behiond when you remove the fuel screw) are removed before you apply the air pressure or you'll lose em. Also make sure your APJ is working correctly. The insides of this gets gunged up reeeeeeal good sometimes and jams/malfunctions. The function of this little gem is to squirt gas down the throat and into the engine just before the revs really start to spin and the air flow into the engine takes things over. I think the theory is that at low engine speed when you crank it open for the first few tenths of a second the air rushes in faster than the gas from the jets can follow so you end up leaning the engine. This squirt compensates for that.

- Have you done the BK mode or other to your APJ to limit the squirt...could be you are getting too much and need to back it off.

- Taffy may insult you :D if you expect to whack it open from idle and get results...something about the engine not being under load so it dont work like it should .... I should know...he got me on that one a while back :)

Other than that if you still have problems you may want to post your jetting and have the experts render their opinion.

WHY? I Can Whack mine from a dead Idle and damn near be dismounted if I'm not careful. My jetting and settings were courtesy of Taffy and JD. The only thing I wasn't crazy about was hitting the rev limiter so early. I had to learn to short shift it, and the power is unbelieveable.

I used to have the same problems with my 400...But not since rejetting and changing the needle to the EKN.

Bonzai :)

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