Ok so I have this 91 cr125 that I've just about given up on. Now I just want to get it running right so I can sell it. Basically its doing two things I can't figure out. 1st is it just keeps flooding its self I have to drag the thing down the street to get it started but once you start it once if you kill it it will restart fine until it sits. Then the plug is soaked and its flooded again even though I instantly turn the gas off. I've cleaned and rebuilt the carb and quadruple checked the float height.

2nd issue is. It's down on power. When I first got it it was fine but in trying to solve the hard starting issue I replace just about everything including top end, plug, crank seals, Now it runs fine just runs out of power. Pulls fine on the bottom hits the powerband then just kind of hits a wall where it won't pull anymore.

Please help I have dumped over 1k into this bike not including the cost of it and I want to try and get some of my money back. As it sits I don't think I'd get much over 500 for it.

something is going on with your float. it may be pooched. or your needle and seat are screwed.

second problem, have you checked for proper powervalve operation?

Yea, it sounds like you need to throw your attention at the carb.  Something isn't working right there.  Needs to be severely cleaned or rebuilt.

Edited by KcDavis, 15 March 2012 - 10:04 PM.

i have a carb from a 99 cr125 for sale if your ever intrested.

In order for fuel to soak the cylinder/plug while sitting, that means fuel is somehow getting in there from the carb ... because the fuel line (from the fuel tank) isn't routed directly to the cylinder, so the only way fuel gets there is from the carb.

I suspect you need to replace the float inlet needle valve, and possibly its seat. Even upon inspection the tip of the valve might appear okay, but a slight imperfection in that mating surface will cause a leak ... especially since the amount of pressure to seat it is relatively light.

To lose power up top is due to a lean/rich issue, a fuel delivery issue, like the float bowl running out of fuel, or an ignition cut-out problem, or a powervalve issue. I would say since you are having flooding issues, that you will likely solve both issues by addressing your carb problem.

I've checked and cleaned the power valve. And I've cleaned and rebuilt the carb minus the needle and seat as the one that came in the rebuild kit was wrong. I'm leaning more towards the cdi as the power problem as my spark is rather weak and I've already replaced the coil and tested the stator. Any other cdi's compatable with this bike? I need this thing gone asap. I have 5 dirt bikes and need to trim the fat

Had the same problems on two different bikes.  One kept wet fouling plugs, turned out to be the needle seat.  The fall flat at midrange and no top end or pull was the powervalve not opening.  I had just rebuilt the top end, and like you was very frustrated.  I swore i had put the powervalve back together correctly, so much i refused to check it.  Pulled the carb three times before i reluctantly checked the pv.   It was not opening, i had pinched it when i put the cylinder back on.  I lined things back up, and it screamed, recheck your pv before you throw it in the lake, glad i did.....good luck.

two strokes are new to me. So when I checked the functionality of the pv after I put it back together I just made sure it slid in and out is there anything else I should check?

1bad88xr250r, on 16 March 2012 - 04:12 PM, said:

I was lucky enough to find an obvious mistake.  In short the exhaust port needs to become larger as the rev's increase.  I'm not super familiar with 91 pv assembly's, but somethings not assembled right.  Do you have a service manual?  If not i found a link you can download a freebie, or find a fiche that shows an exploded view and make sure it went in properly.  It isn't opening.  I am hoping someone on here will chime in who knows more specifics to that year.  The guys in this forum are always helpful, be patient and you will get it going!

ya I have the service manual. Went by that when cleaning the pv. The bike has been in storage since october so when I pull it out I will be sure to recheck. The pv on the 91 is rather simple.

Your manual will also tell you how to check to make sure the powervalve is operating properly.