Idle problems - wide open!

The other day my son took the bike (05 crf250x) for a ride. It was hard starting as it had been sitting for a while. Once we got it running, he took off. A little later he came back. Pushing the bike. He said that the throttle had stuck on full! The throttle grip was stuck and would not turn. I got around to checking it out and with the carb removed found that the slide was stuck in the down position. It turned out the needle was stuck. I freed it and and reassembled the carb checking along the way that the cables moved freely and the slide also. Once the bike was back together, I fired it up and it went straight to full throttle! The grip moves freely, you can hear the slide moving up and down (with the bike not running).

I'd like to here any suggestions as to possible problems I should look for. I have done a bit of reading around and will start with the Pilot screw (aftermarket) and check spring, washer, and o-ring. Other than that, I'm at a loss.

Any help would be great!



If your slide was stuck, what did you do about the slide plate and slide plate seal?

You need new ones.

If the bike has been sitting a while and ran normally before you parked it. Then most likely your carb got gunked up and causing improper vacuum on your jets.

Did you open you carb bowl and clean out. If your pilot jet is clogged and bike is able to start, for example, with the choke 'on' and goes directly to full throttle that could actually be a very lean mix causing this. just a suggestion. and can't hurt to clean.

Thanks Guys, Yes the bike ran fine prior to parking it. I did blow out the jets with carb cleaner. I will have to look at the slide plate and seal as I did not mess with them. What was actually "stuck was the needle that goes through the slide and into the jet located in the bowl. Sorry don't know the names for these parts. The needle was stuck in the jet. I popped it out from the bottom and went to work on cleaning the jets as I figured it was gummed up due to sitting. It did look pretty clean but then again the needle was stuck.....

Thanks again,


DO NOT USE CARB CLEANER on a motorcycle carb!

Unless it's MC specific. You can melt the inner seals............

You need to replace the the pilot and leak jets, apump parts, clear the apump nozzle, use spray brake cleaner and compressed air, and follow the re-build guide.


Edited by Krannie


Yeah, I saw that information after I started the first time.... Living and learning all the time!

I did the rejet a while ago and don't really remember what they were. Perhaps 42 and 155? Does that sound about right, CA riding anywhere from 2000 to 7000'.... also the acc pump.

Thanks for the link to the rebuild info. I'll get to it when I return from vaca.

Follow-up questions... You say to replace the items, is better, easier, or just the right thing to do? Just wondering....

Again, thanks for the continued input! I'll post a follow-up once I return.


It's basic maintenance.

The carb is a system.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now