Help!!!!

[dg95]

I have an 03 z400 that sat for about a month and now seems like it is hitting a rev limiter. it is not the carb or valves or air filter or cdi or ne thing simple two mechanics and i have gone through it i'm waiting to trade it in for an r450 and the 400 is currently sitting at the suzuki shop having them find the problem but they cannot identify it either. We are guessing that it is a sensor or something like that. has anyone had a problem similar to this? if so help! i want my new r450 in the worst way

[jaredZ400rider]

this happened to me about 2 weeks ago. i took it to nacs and they took the whole carb apart and found nothing so they just cleaned it and put it back together but it still would bog out at about half throttle. they took the carb apart again and they found a little piece of something clogging it so it wasnt getting enough fuel.

are you sure its doesnt have anything to do with the carb. it sounds like it isnt getting enough fuel or running to lean.

[dg95]

it is getting enough fuel because the pipe collects gas and then spits a flame out, the spark plug is fine. the guys at suzuki put a different cdi on my quad and it did the same thing but then they put that cdi on a different quad and now that quad is doing the same thing.

[huffdaddy_400EX]

Can you be a little more specific about "hitting a rev limiter"? Are you saying that when you start the quad it's like you have a hand full of throttle....the engine is over rev'ing? I'm just a little confused by the post.

[jaredZ400rider]

i dont get how it would just all of the sudden act like its hitting a rev limiter. were you playing around with anything? it doesnt make any sence

[dg95]

i just started it up and it was acting like this and it sounds like when you are going in reverse and it has a rev limiter that only allows you to go so fast and if you go past that limiter is pops and wheezes you know what i'm talking about?

[huffdaddy_400EX]

Have you checked the choke? I had the same issue with my z400. I some how had gotten something in the choke chamber (came through the cable). When I started it up it over rev'ed and hit the limiter....scared the sh%% out of me. Try pulling the choke off the carb and look inside to see if there is an obstructions (it should slide in and out with ease). In my case there something blocking it and as soon as I removed it and cleaned the chamber out with carb cleaner everything was fine.