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Why does my 04 cr250 not idle?!?!?

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Well just like it says my bike will not idle, to the point where when descending a hill on technical trails with the clutch depressed it will conch out. It drives me nuts! my 01 cr250 would idle all day long, no problems, but after obtaining my 04 it will NOT idle even with the idle screw all the way in. I have a fmf gnarly, fmf shorty, v force 3's, clean air filter, new plug, 410 main, 2nd clip needle, 32.5 pilot, and air screw 2-2.5 turns out ( i know i should probably to go down on the pilot, just havent gotten to the local shop to pick one up).

I would like to know if there are any suggestions, OTHER THAN 2 STROKES DONT IDLE, b/c all of my friends idle just fine, or atleast 15-30 secs, not 5 secs like mine if im lucky. I did notice my throttle tube was cracked and need to replace it, but i didnt think that would have anything to do with it, would it? I have even tried to adjust the metal wheel on the throttle cable to add tension with no luck. I have tried all settings on the idle screw, in, out etc, for the bike to even sit at idle for mere seconds the idle screw has to be recessed inside the lock nut. Suggestions?

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the throttle tube is probably what it is... or a vacuum leak somewhere else.. you could have a pinhole in an intake boot and it'll idle like crazy high or wont.. your idle jet/circuit could be dirty/clogged too..

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Yeah, well that would be my last resort so far as finding a way to get it to idle would be the throttle tube but next on my list. I know its not an air leak, and i have removed and cleaned the carb multiple times. Which circuit in the carb would be my idle circuit, i couldnt imagine it being dirty seeing as i just fully removed and cleaned/blew out the carb before my last ride?

I did notice this, and seeing as it is hard to explain i will have to post pictures. But just in case yall can understand, on the reed block side of the carb in the bottom part of the opening there is a pinhole, (maybe idle circuit?) and it looks like someone has taken sandpaper, or a dremel with a light grinding bit on it and run it back and forth over the opening, is this some type of "mod" or maybe the hole was damaged and they tried to smooth it down?

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it honestly seems like the throttle tube though... because it's set to block air at idle so the mix doesn't become too lean, if it opens up, cracks splits, is stuck, in wrong could cause it..

post pics of that thing though, because it could be important.

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yeah, i will have to get a new tube, but i will try and get some picture up tomorrow of what im talking about. but the tube was cracked and i put new grips on then safety wired them wouldnt the safety wire hold the throttle tube together? either way ill get some pics up tom of what im talking about

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ohh! i thought you said like throtle slide like in the carb.. 👍 if it was your twisty tube it wont make much of a difference, if you have to you can super glue that back together to makesure it's not sticking but then it might be that hole you're talking about! or loose airboots something, gone through thouroughly 3 times looking for vaccum leaks? wd40 test?

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First things first, replace your throttle tube. Ever hear of a throttle sticking wide open? How about murphy's law? With a broken throttle tube you're just tempting both of them.

Have you checked your reeds? Check them from chips/fraying. Also verify that they sit firmly on the reed block and no light shines through.

Then remove your pilot jet and put a new one in. This jet has the smallest opening, therefore it is the easiest to clog and hardest to clean. You can blow carb cleaner and air through it all day long and not touch varnished gas. They only cost a few dollars.

One thing that should be mentioned, is the age of the top end. If your top end is way past it's service life, then don't expect much. If it has a fresh top end, it should idle assuming everything else is in order.

Throw a new spark plug in there while you're at it, and preform a compression test. The compression test can give you a good idea of the quality of the rings and also give you a number to base future readings off.

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OK, inspected the reeds, they look brand new, what is the WD-40 test? is that similar to automotive vaccuum leak test where you spray break cleaner around a manifold lookin for a change in rpms?

Also, tell me if this makes sense a jetting recommendation from a local shop. My bike runs on in high rpms when depressing the clutch. (the gung gung gung noise), with the air screw at 1.5-1.75 turns out. NOW i put the air screw at 2-2.5 turns out and the gung gung gung stopped. Well i understood the running on to be a lean condition? SO why would leaning it out even further help stop that? The guy who owned the shop who is a two stroke rider said try moving the clip to position 3 vs. 2 (down from top), 400 main vs. 410 main, and leave the 32.5 pilot, and start at 1.5-2 turns out and see how it runs. And last time i moved the needle to clip 3 with the 410 main and 32.5 Pilot it wouldnt even clean out, so why would the 400 run better prospectively? Can yall explain this reasoning?

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