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my rm is gutless.

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Ok I have an 01 RM250 I have owned it since 2007 it was basically beaten to hell when I got it and I spent the last 5 years rebuilding it little by little. I'v tried everything

-pipe was dented so I had that repaired.

-I rebuilt the powervalve cleaned it and it functions perfectly now

-Carb is in perfect working order (jetting is almost spot on depends on the weather)

-I had some motor work done to it during this rebuild, I had the cylinder ported and the head cut to run 100 octane

-I tried a different reed cage and different reeds and there were changes but nothing serious

-I am running an oem piston with rings compression is very good

(note: I just finished doing a full motor and tranny rebuild all new bearings in the top and bottom end everything rebuilt)

Some people are going to say that's just how much power the bike has, well I owned a 98 rm250 and that was a much faster bike. Hell my trx250r quad is faster then this dirt bike. my 98 rm250 used to destroy my friends 450 quads my 01 is way behind.

any suggestions?

Edited by sangheraent

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my gearing is 13/51. I can only imagine how bad it would feel if I had stock gearing. Im not losing in a race at top speed my power loss starts from the bottom all the way up. top speed doesn't matter to me I only use the bike for MX

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is the pv set right? you should loosen it off so it unwinds then twist it till it clicks and tighten the retainer back up....only takes a minute

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Port timing, hopefully a reputable shop did the work. And where is your squish set at (gap and width)?

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The shop is very well known built 2 of my other bikes and they haul total ass. however my bike had no power even before I ported it. I don't know the squish I can check it out.

I have tried tons of different PV adjustments it doesn't add power just moves it around.

My two biggest suspects are the carb or the silencer. My silencer is a spark arrested fmf Q series in rough shape. Maybe its blocking air movement?

My carb Im not sure how to test the powerjet deal.

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How is the reeds and jetting? is the powervalve connected? Is there a hole in the engine somewhere? Is the jetting correct? Is the piston the right size? Check the reeds out too. It very well could be electrical also.

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The shop is very well known built 2 of my other bikes and they haul total ass. however my bike had no power even before I ported it. I don't know the squish I can check it out.

I have tried tons of different PV adjustments it doesn't add power just moves it around.

My two biggest suspects are the carb or the silencer. My silencer is a spark arrested fmf Q series in rough shape. Maybe its blocking air movement?

My carb Im not sure how to test the powerjet deal.

This is my guess

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Powervalve is connected and rebuilt.

I tried 10 different stator timing adjustments and some were better then others but I just put it back to stock at the end of the day.

No air leaks on the motor, plating has about 30 hours on it, piston is brand new and so are rings.

It could be electrical I guess. I can test everything, from my personal experience electrical causes jetting issues and I don't have those.

Spark arrestors get clogged? I did not know this? I might rip open the silencer and see whats going on I repacked it last season. but didn't mess with the spark arrestor.

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Powervalve is connected and rebuilt.

I tried 10 different stator timing adjustments and some were better then others but I just put it back to stock at the end of the day.

No air leaks on the motor, plating has about 30 hours on it, piston is brand new and so are rings.

It could be electrical I guess. I can test everything, from my personal experience electrical causes jetting issues and I don't have those.

Spark arrestors get clogged? I did not know this? I might rip open the silencer and see whats going on I repacked it last season. but didn't mess with the spark arrestor.

FMF Q won't clog at the S/A there is simply no way unless you flip it muffler end into a dirt and jam crap down it. There is a faint possibility the perforated core of the muffler part broke and has collapse blocking clean air flow. tear it apart and replace the packing anyway.... new packing and you eliminate that possibility. Win/win. :)

You mentioned you had good compression... how much did you have?

Had a buddy put a piston in backwards the night before a race and it ran but ran like crap. Just a thought.

You said the jetting is spot on. What are you running, other guys on here may notice if something is possibly off.... I am not one of those guys. :)

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Ok i took apart my silencer and the thing was completely destroyed, So I bought a powercore 2.

now with the new silencer but is the exact same but quieter.

Im getting very good bottom end medium mid-range and nothing up top. I'm thinking maybe the clutch is slipping? but it has good bottom end, iv ridden a worn clutch before and it slips everywhere. Any thoughts on this?

Im getting lots of rev but no power on the ground.

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Ok i took apart my silencer and the thing was completely destroyed, So I bought a powercore 2.

now with the new silencer but is the exact same but quieter.

Im getting very good bottom end medium mid-range and nothing up top. I'm thinking maybe the clutch is slipping? but it has good bottom end, iv ridden a worn clutch before and it slips everywhere. Any thoughts on this?

Im getting lots of rev but no power on the ground.

Take a look at your clutch plates. 10 minutes and you'll know for sure.

Or if you have a paved hill you can ride up pull a high gear (4th or 5th) and wack it. If it comes on pipe hard but you're not accelerating hard you know your clutch is slipping.

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Sure you're not riding it like your quad, waiting too long to shift, and over revving it??? Over rev a 2 stroke, and it will make all kinds of rpm, go nowhere, and feel gutless.

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I would definetly check the piston like others said.

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Ill have a look at the piston and check the tolerances on the clutch, I remember distinctly putting the arrow pointed forward unless its suppose to be the other direction. (ill double check the manual just to make sure. )

Iv been riding this bike for about 5 years so Im confident I understand its power and my quad is also a two stroke.

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