Jump to content
Sign in to follow this  

Dies at 0-1/4 Throttle

Recommended Posts

I have a 2005 wr250f, and have had problems with it since I got it out from winter storage. When I first took it out the float was stuck and it would constantly drain gas with the petcock on. So I took apart the bottom half of the carb and cleaned the bowl, main jet, pilot jet, starter jet, and everyting I could get to from the bowl.

Now the bike will not idle at all without the choke. It starts up perfectly with the choke pulled out but as soon as you push the choke back in it immediately dies, no sputtering at all, just shuts off. It sounds like it is running perfectly with the choke pulled out, it isnt idleing high or anything, so Im guessing it's running lean somewhere. I am able to ride it or let it idle with the choke off as long as I am holding the throttle open. But if I close the throttle with the choke off it will instantly die. I have the idle screw turned in to where it's getting pretty hard to turn it anymore but there is still a good amount of threads left, but I dont think this is the problem.

I think that there must be something new wrong with it, and not just needing a new pilot jet because it ran perfectly in these temps in the past. This has all been happening in the 40s and 50s, which isnt really that cold, it has ran fine before in colder temps. The main jet was changed to 172 last year and I have the pilot screw set at 2.5 turns out. What could possibly be wrong?

Share this post


Link to post
Share on other sites

I'm pretty sure that my problem is with the pilot circuit. I still ahve the stock 40 pilot jet in it, which seems small, but hasnt been a problem for me before.

Moose - I cleaned my pilot jet yesterday, and no change. I soaked it in carb cleaner for a while, poked around in it with a fine wire, and blew air through it as much as I could. It looked clean as far as I could tell and I could see through it after I was done cleaning it. So I don't think that there is a problem with the jet itself.

Share this post


Link to post
Share on other sites

Any other ideas on how to fix this major problem of mine?

Share this post


Link to post
Share on other sites

what is your current jetting? all stock except for the main? have you cleaned out the whole carb? you said the float was stuck. was it gummed up from old gas? what does the bike do when you twist the throttle with the choke on? have you cleaned the pilot air jet? did you double check that you are not missing the o-ring or washer on the fuel screw?

Share this post


Link to post
Share on other sites

I believe that the float was stuck form old gas. The fuel screw has never been removed, so I would think the washers and o ring is there. I cleaned out the float bowl, float, needle valve, starter jet, pilot jet, and main jet. The only changes made to it are the pilot screw is set at 2.5, main jet of 172, and the needle was moved one clip to make it richer.

The bike will run fine with the choke on. I can ride it around with the choke out as long as I keep the throttle constantly open. If I pull in the clutch while riding it and get off of the throttle it will instantly die. It sounds almost perfect with the choke on.

Share this post


Link to post
Share on other sites

Is your idle set too low? Try turning it up. You never no some little kid might have been standing there and got bored and started turning things.

Share this post


Link to post
Share on other sites
did you have the slide out of the carb?

No, the only time i have messed with anything besides what I could get to form the float bowl was when I adjusted the needle.

And my idle setting isnt the problem, ive tried changing that around as well.

Share this post


Link to post
Share on other sites
hot start being held open?

I thought it might be a possibility considering i have taken it off so many times recently in order to clean my carb. Would I be able to tell form the lever if it was open? Like would the hot start lever just be lose and floppy back and forth?

Share this post


Link to post
Share on other sites

it would probably be loose. start the bike and pull the hot start lever and see if it changes the motor. if it does then it is most likely working ok, but i would pull it out just to see.

Share this post


Link to post
Share on other sites

Dunlop, Im having the same problem with my 2001 yz250f. I cant get it to run at all with out the choke on. I just took the carb off today and cleaned the entire carb and checked to see if all the jets were the at the stock settings. Im ordering a 03 cam because its a pain in the a$# to start cold or hot. Let me know if you solve this problem. I will do the same. Good luck

Share this post


Link to post
Share on other sites

Ok, so I feel pretty stupid now:blush:. My idle was just set too low:bonk: . I had checked it many times and thought that I had almost all the way turned it because I was not able to turn the idle adjuster any more and the spring looked fairly compressed to me. The problem was just that the cable had gotten twisted up and caught, probably from taking off the carb so many times. Thank you very much for all your guys input.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

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

Reply with:

Sign in to follow this  

×
×
  • Create New...