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Odd power delivery question on 92 rm125

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So Ive gotten my rm125 to run were i want it too. Everything is pretty much factory stock except for boyseen reeds and a uni filter. Its run great except if i slow down too much going up hill. Itll still run but be very boggy. Now if just touch the clutch lever and pull it in the slightest amount the bike will snap back to its normal life. itll race right up the hill as long as i have slight tension on the lever and i mean slight. Basically just rest my fingers on it. I though it was a clutch issues but adjustment appears to be fine and the clutch looks good. It doesnt slip at all and has no other signs of issues.

Anyone got any suggestions or ideas? Cant be jetting can it?

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125's aren't good hill climbers, here's a couple things though, engine compression, should be 150 psi or better, float level setting too low and it'll starve for gas going uphill, or maybe a bigger rear sprocket, but you'll lose on top speed w/ the bigger sprocket, clutch feathering is the only other option, which you already discovered.

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Im not sure what im doing is actually feathering the clutch. Im pretty much just resting my hand on it slightly and thats enough to snap it up. racing around all other times and im fine. Its just when it starts to bog down thats the only way of fighting it. If i go up a not so big incline at a decent speed ill be fine but if i slow alittle bit itll start to bog then i just touch the lever and im off. Also when i do a burnout off the line I have to have the lever in ever so slightly again or itll just take off slowly. Maybe ill relook into the carb again.

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I would also suggest checking your power valve and making sure it's functioning correctly.

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pffft. 125 can't hill climb what a bunch bs, I have a 97 rm 125 and I trail ride the hell out of it. Of course you're gonna bog out if you attempt it at 2 mph, but as long as you gas you a little you're gonna be fine.

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i'm pretty sure your powervalve spring is tensioned too hard

so the valves open a bit later, your clutching is helping it rev so they open

or they are just dirty so they don't wanna open quick enough

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Im gonna give the powervalve a cleaning first since its probably never been done. I do think its adjusted to have more tension but ive never delved into it to much for fear of it breaking. It already looks like someones been in the pv area with a hammer and chisel. The knob is busted and the screws holding the opposite side cover on are pretty torn up. Ive been worried if i get into it i might break something inside so i left it be.

Whats the recommended steps to cleaning it as easily as possible? I know i should probably pop the head off but id rather not. Should i just take off the side cover and spray away with carb cleaner and take some tension off the knob as well. I know i should be going in the front cover to really clean it but the frame is in the way so id have to drop the motor to really get at it. What are the chances of me breaking th elittle clips that hold the pv assembly together while cleaning it are?

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If you haven't opened up the top end yet you should do it now. You can inspect and clean the pv, install a new ring and gaskets for less than $30.

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If you haven't opened up the top end yet you should do it now. You can inspect and clean the pv, install a new ring and gaskets for less than $30.

your probably right. Unfortunately the last time i had a 2 stroke apart was back in the 80's. Ill have to relearn how to do it again. I cant even begin to remember how to do it.

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you can't do much wrong on the top end of a 2 stroke

dont forget to let the coolant out, that was my first mistake i ever made :lol:

and a pretty bad one ^^

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