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Rm250 why you so slow !

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Hey guys i just traded my good 06 yz125 for a 01 rm250 . The motor was just rebuilt , bike seems nice . Heres were im baffled ... The rm is very torquey but has no mid or topend .. My yz125 would smoke this rm250 bad ... The bike is stock other that. The fmf gnarly . Which ik takes some topend away .. But this bike should still beat a 125 imo... Im on stock jetting i just pulled the carb and checked . The bike is got a little bit of spooge coming from the pipe . Im going to either drop a 155 main or a 160 coming from the stock 162 in hopes to liven this thing up a bit. Any sugestions ? Thanks

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Check ignition timing,clutch for wear,piston worn? Thick base gasket? Has to be something.

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...power valve opening?

Yup..that could do it

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so i put the clip on the second groove on the needle  and installed a 160 main ,   i made a video of the powervalve it seems to be working fine when i rev it out of gear but in gear the valve doesnt seem to open all the way

Edited by yamaha racing 230

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another update so when the bike is outta gear and i stab the throttle wide open the valve opens halfway ...  what do you guys think this is ? if i blip it half way it opens fine 

 

also i zip tied the powervalve in the wide open position , took it for a ride... felt like a 250 should with a gnarly pipe jetted on the rich side ...  so now i  gotta figure out why it doesnt want to open all the way when i pin the throttle

Edited by yamaha racing 230

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Im pulling the cylinder off tomorrow to pull the valves . I think they need to be cleaned .. I can get the valve working by holding the throttle halfway open for about 10 seconds than the pv opens and stays open and will randomly close .

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the actuator goes fully up, so that is not the problem

the problem are the 2 little "pistons" on the side of the powervalve

they have a groove in it, which make them twist when going out and in

after some the time the groove wears out and those pistons don't move fully out

 

had the same on my 04, right side was completely worn

pretty expensive &%$#@!ers too

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the actuator goes fully up, so that is not the problem

the problem are the 2 little "pistons" on the side of the powervalve

they have a groove in it, which make them twist when going out and in

after some the time the groove wears out and those pistons don't move fully out

 

had the same on my 04, right side was completely worn

pretty expensive &%$#@!ers too

This could very well be the problem ~ take the time and check it out.

 

Also note that if it's working when the bike is in neutral but not in gear then you may not be rev'ing the bike out as much when it's in gear.  Hard to say what's causing that, pulling the cylinder and inspecting the complete valve is a good place to start.  Carb, reeds, ignition timing and even a plugged up silencer could be the cause or at least contribute.  So go after what you can and take your time as it's impossible to know what a previous owner may or may not have done.

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The 01 RM250 is not a slow bike. My father rides the same machine. I have ridden it three times after his rebuild and it pulls HARD. Has minimum bottom, but when I get to the mid and top it feels like it won't stop pulling. Sad to say but it out runs my YZ250 pretty easily. Of course mine is geared down for trails, but still I stand no chance.

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Check out the Solenoid valve for the exhaust valve. if it is all gummed up which most of the time they are it won't operate the PV correctly

 

solenoidevalve_zps2018ae91.jpg

 

Also check your PV tensioner on the side. this should only have about a 1/4 turn on once you start getting tension on it. Too much and the PV won't open correctly.

 

IMAG0023.jpg

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Also i ordered a new actuator when i pulled it apart you could feel slight grooves that the ball bearings ride on . Also ordered new boysen pro reeds and a procircut r304 silencer .

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