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RM 125 Problems

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I have an RM 125. Not sure of the year but its late 90's, maybe 97-99. Anyways it has a bog on the low end and I have to kind of rev it, bog, rev it, bog, rev it, and then it will hit the power band. Im trying to figure this out so it doesnt have this problem. It has a Pro Circuit pipe with a 170 main jet and a 50 pilot. The plug was brownish black. It was definitally darker than usual. Im going to run a new BR9EG plug today and see if that makes a difference. What could lead the bike to do this?

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when was the last rebuild?

when were the reeds replaced last?

If everything is fairly new you can try adjusting your airscrew, in = richer - out = leaner

Your saying bog, a bog normally indicates a lean condition

A blubber/stumble = a rich condition

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It is spose to be recently rebuilt. It has 120lbs of compression when the motor is cold. Spose to have boyesen reeds but never looked into that. I richened it way up and its still boggy. Its just right before the powerband tho. I can feather it into the powerband and let her scream but if i just lay on the throttle it will bog bad. Any more ideas? could it be something as simple as my mixture? or my plug? Im running 32-1 with klotz super techniplate. I need to pick up a couple new plugs and try them out. BR9EG, BR9ES, BR8ES. Any more help is apprieciated. Thanks

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It is spose to be recently rebuilt. It has 120lbs of compression when the motor is cold. Spose to have boyesen reeds but never looked into that. I richened it way up and its still boggy. Its just right before the powerband tho. I can feather it into the powerband and let her scream but if i just lay on the throttle it will bog bad. Any more ideas? could it be something as simple as my mixture? or my plug? Im running 32-1 with klotz super techniplate. I need to pick up a couple new plugs and try them out. BR9EG, BR9ES, BR8ES. Any more help is apprieciated. Thanks

The supposed to be recently rebiult doesn't fly, i've seen almost ever bike forsale with the recently rebuilt listed on it. I'm not sure what you should have for compression but that seems low to me i'd have to guess i'd say around 160psi would be better for a supposed fresh rebuild.

Check for air leaks?

If the crank seals are bad on the flywheel side it can cause a lean condition, if you pull your pipe off and look into the cylinder you can get a rough idea of the condition of the piston and cylinder. I'd also check your reeds while your at it and make sure they are not frayed/chipped and setting flush on the reedblock

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