First of all I would like to thank RM_guy Dave for giving me a stator for my 01' RM 250 completely free, he wouldn't even let me pay shipping! I finally put it in last week and the bike ran great again, but i thought it was slightly lean.. I lowered the needle jet clip one position and it was a little boggy so I raised it back up a notch (3rd position). Went to run the bike and i accidentally ran it out of gas, but it seemed to idle fine if not a tad low before. Today i loaded up with my buddies to go ride and fueled up, it was very hard to start since I ran it out of gas. Finally it fired up and reved like wide open throttle as if I was running it out of fuel, but I was able to kill it with the kill switch. I kept starting it and shutting it off thinking maybe it just needed to get more fuel through the carb and into the motor, but nothing changed. I know when a crank seal went bad on my old RM it did the same thing, but this one was just running fine before I ran it out of gas and messed with the carb on it. I pulled the carb off and the slide wasn't stuck or anything, and the boots were all snug. Definately seems like an air leak, could it be coming from the top of the carb where I pulled it apart to adjust the needle jet? I'm really bummed because I just got it running again and couldn't even ride...
More problems with the RM 250 Reving like crazy!
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Yeah doesnt that make it rev up or something if you find the air leak though? I'm afraid to start the bike again honestly... I started it once and it was idling high, but not reving wide open. You could tell it wasn't running right though, then after about 20 seconds it started to rev wide open again. A few times I had to put it in 4th gear just to kill the motor, and I'm afraid its going to blow up if I keep starting it!
Yeah, or perhaps the float is getting stuck closed. You can tap on the bowl lightly with the handle of a screwdriver and see if that helps. If you turn the fuel on and lean the bike over toward the left does it start peeing fuel from the overflow? If not, there isn't enough fuel in the bowl, or the overflow line is clogged.
Hey Chris, glad you got it running...sort of ;)
Check to see if the throttle cable is hung up and not letting the slide in the carb close all the way. When you release the throttle (without the motor running) you should hear the slide bottoming out in the carb. If not, the check the cable routing to make sure it isn't pulling somewhere.
Check to see if the throttle cable is hung up and not letting the slide in the carb close all the way. When you release the throttle (without the motor running) you should hear the slide bottoming out in the carb. If not, the check the cable routing to make sure it isn't pulling somewhere.
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I checked the cable and its not getting hungup anywhere, and when I lean the bike over its flowing fuel out the overflow. I'm hoping when I cleaned the inside of the stator case with WD40 it didnt dry the seal out? If thats the worse case scenerio,
could I change the stator side crank seal without splitting the cases?!?
could I change the stator side crank seal without splitting the cases?!?
2strokerfun
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- May 19, 2006
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It's within the realm of theoretical possibility that running the bike out of gas could have been the final straw on a old seal... Still, my money's on the carb.
Could the clip have come off the needle and let it slide up? I'm baffled and not sure what it could be. Sounds like you checked all of the obvious stuff. You may want to tear into the carb again just to make sure it's all Ok.
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I'll take it apart and check the carb out today most likely, I haven't yet because it's getting fuel and the slide was working properly. I wish it would be the needle clip fell off, that would be great. One thing I'm definately going to check, because your the man Dave and anything is possible =D
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Well i tore the carb apart and the clip was in place fine, and the stock needle & clip is about 3 months old. The main jet is clean, but whats a good tool to use on cleaning the pilot jet? Heres the other thing I thought of... It was completely out of gas, and I forgot my gas can when we went to get fuel on the way so I had to mix it in the tank. I know its not good, but i shook the heck out of the bike and we had a bumpy ride there. It was smoking when i started it normally, just reving wide open. It did seem the fuel in the carb appeared to have alot of yamalube in it, I could tell the color was deep red but I don't think that would take away enough fuel for it to run that lean...
if the throttle is shut and it is reving then you are getting air in either by way of the carb seal reed block or the left crank seal...was it that hard to remove the flywheel and stator??
only thing I'd be checking in the carb is the piliot circuit and air screw.... have you turned the air screw all the way in and tried starting?? I think that would eliminate the idle (piliot)circuit....
only thing I'd be checking in the carb is the piliot circuit and air screw.... have you turned the air screw all the way in and tried starting?? I think that would eliminate the idle (piliot)circuit....
you tell us ...when you had the flywheel off did you look at the seal?
if you can see the entire face of the seal then it comes out from the outside ..if you can't see the outer edge of the seal due to the engine casing coming around the front then you will have to split it.
if you can see the entire face of the seal then it comes out from the outside ..if you can't see the outer edge of the seal due to the engine casing coming around the front then you will have to split it.
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When I had the flywheel off I was looking at the seal, it appeared to be in decent condition and looked like you could replace it without splitting the cases.
I was just wondering if anyone else has done it on a late model RM 250 so
they could give me some advice.
I was just wondering if anyone else has done it on a late model RM 250 so
they could give me some advice.
I've never done the left side seal but when I get home tonight I'll see what the service manual says.
Its do able, but why? Because you think its leaking? Does it appear to be leaking, sprinkle baby powder around it? Does it appear even and flush with the chamfer in the bore? Spraying brake cleaner should make it rev higher? Does your choke knob spin down for higher idle? The air screw and choke have no effect? You actually have free play and hear/feel the slide slam? Vintage Bob
Crap, I forgot to look at the manual on the seal replacement. I had some car trouble last night. I think you can change it without splitting the cases though.
Actually it's an old trick when you are out on the trail and expect to need to fill up at a gas station. You carry enough 2 stroke oil to mix in with pump gas and mix it in the tank.
Good luck with the mixing pre mix in the tank theory. Not the best method agreed, the cause of the lean condition? How? Too much oil, like more than 18:1? Erratic throttle response at best, if you could keep it running, not a solid rev to the moon.
RM_guy said:
i'm with you man the only difference in the bikes gas tank and the gas can is the shape and size.
while at the pump I put in one gallon then all the oil for 2gal, then add the last gallon, hold the front brake and push -pull a few times...finished
