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RM250 Power Valve Adjustment.....how do you like yours?

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I've got an 04' RM250 that I ride mostly on woods type trails.  It's mostly 1st, 2nd, 3rd gear stuff.....over stumps, over rock ledges, with some fast flat stuff every now and then.  

I bought the bike a few months ago and have put around 6 hours on it so far according to the hour meter.  I've read here on the forums that a lot of guys like to crank down the power valve spring making it tighter, so the power valve opens at a higher RPM.........they say that it "gives the motor more torque" for lugging through woods trails and tight single track stuff.  

Well, I've been playing around with the power valve settings a bunch......I've ran it at the stock setting (180deg clockwise from no tension) to an extra 1-1/2 turns clockwise (tighter) and everything in between.  From what I can tell......tightening it up doesn't really give the motor any additional torque.....it just delays when it comes into the pipe....making it a little smoother, making the rear tire hook up a little better if you get to greedy with the throttle. It definitely doesn't' rev as fast with the power valve cranked up tighter.  I've got an FMF Gnarly pipe on the bike which has lots of bottom end, but runs out of top end pull pretty fast.  When I have the power valve springs cranked up an extra 1-1/2 turns tighter than stock......by the time the rpms get up high enough to get the power valve to open, the motors already out of power because of the pipe.

After playing around with the power valve during several trails rides....I've went back to the stock setting.  It comes onto the pipe fast, but I'd rather have the power available and be able to back off the gas if needed (or work the clutch if needed), then not having the power there at all if I need it. With the Gnarly pipe, it's got plenty of low-end power to chug up hills and obstacles.....and when I get onto the gas, and it comes onto the pipe....I've got more power than I need. I like it that way. It just feels neutered if I crank up the power valve spring....like it's lost all it's muscle.

How do you guys have your RM250 power valves set up? 

Thanks for the info! 

Edited by IQRaceworks
Wrong pipe

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Stock setting on my 03. Sounds like you have a gnarly instead of fatty

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Crap...yep, you are right!  Not sure why I said Fatty....let me fix that in my original post. I've got a Gnarly.  Thanks for catching that! 

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I run my 03 with 1/4 turn, and a Fatty FMF. I played with 0 turn for a while, then split the difference.

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The stock PV setting and a FWW seemed to give me the best combination when I had my '08 RM250.

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3 hours ago, IQRaceworks said:

1/4 more than stock setting? Or 1/4 turn more than installed position(full lose) ?

1/4 turn more than full loose.

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I put a 04 cylinder and power valves on a 06 bottomend(built a bike from parts from 00-07) to go with our 07 rm 250 and the 04 bike hits harder then the 07 and didn't pull as good on the bottom as the 07,so I got a reed spacer that's on the 05 on up and put that on. Funny what alittle spacer can do! I messed with the power valves alittle before putting the spacer on but it didn't get us what we wanted and that's when I noticed the 07 had a spacer on it, so on it went and that worked just great. 

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