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Rm 125 powerband

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Hii,

could you tell me please how i can ajust the powerband to make it kick in earlyer and make it just more rapid ?? :worthy:

thanks x

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just tighten it all the way, or get a red one.

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okayy thankyou,, so when i take the power valve cover off which part do i losen ? and also how sensitive is it so will i only have to turn it a half a turn or do i need to turn it alot? :worthy:

thankyou

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What year? I have a 1996 and it IS adjustable without removing any parts.

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I don't know if the PV is the same as my '96. If it is, there's a mechanism on the left side (sitting on the bike). It is basically kind of a "knob" that is held in place by two 8mm head bolts and a plate. It almost looks like a petcock or something, but is part of the side of the cylinder. By loosening the two bolts you can turn that knob in and out and adjust the tension of the spring that keeps the pv closed. The tighter the spring, the harder it is for the PV to open so it is delayed. The looser the spring tension, the easier it is for the PV to open and it opens earlier in the rpm range.

Do you have a service manual? I never own a bike without one.

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If your not sure what to be turning and how much to turn it. Then I think you should leave it alone. Just my 2 cents.

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If your not sure what to be turning and how much to turn it. Then I think you should leave it alone. Just my 2 cents.

+1

Seriously, if you are not sure then you should not mess with it, it's too easy to go the wrong way. Talk to a mechanic.

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I just bought a 2002 RM 125 off of CL. I had to put a new top end on the machine, including the cylinder. When I switched the power valve over from the old cylinder to the new cylinder, I set it at one full turn from the alignment mark as I always have on my 250. I have not run the bike yet, but just pushing on the power valves they feel really stiff. My RM 250 and my CR 250 are both easier to push in. I guess the final test will be the ride. The funny thing is they only feel tight right as they start to move, then it gets easier. I might need to add a little 2 stroke oil to lubricate, but I'm thinking I'm going to have to loosen the spring tension. What do you all think?

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You are joking right? This has to be a troll....

everyone must gain detailed knowledge of their bike automatically when they start riding and never ask a noob question once. I get it

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I got mine fired up and have already run the heat cycles and it is ready to ride. The powerband definitely kicks in later than on my 250's, but just wants to keep pulling once in it. Is it normal for the powerband to come on late in RM 125's? I'm new to 125's. I bought this bike for my daughter, but I'll be putting some hours on it. It's fun to ride. Doesn't have near the low end of the 250's. I guess I can try to loosen the spring to get the hit faster per an earlier post.

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You are joking right? This has to be a troll....
:worthy:

The guy is asking how to do it before he has a go.

I thought that was the general idea of a forum like this?? Not just an area for those who already know to mock those who don't.:ride:

If he had come on here saying he had already messed with it and cocked it up he would deserve a far worse panning, so why give him it now when he is trying to do the right thing?

That said, buy a manual mate, you will need one in the end.:thumbsup:

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Yesterday I tried to loosen the spring by turning the adjuster about a quarter turn counterclockwise. It had no affect at all. Is anyone on here sure that loosening the spring will cause the powerband to come on faster or do the RM 125 powerbands all come on late?

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A dyno might pick up the difference, other than that send your jug to Eric Gorr or RPM and go with a bigger bore.

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Yesterday I tried to loosen the spring by turning the adjuster about a quarter turn counterclockwise. It had no affect at all. Is anyone on here sure that loosening the spring will cause the powerband to come on faster or do the RM 125 powerbands all come on late?

Turn anti clockwise to loosen spring pre-load therefore comes on band at lower revs but with milder hit.

I've never needed to mess with mine but have read that any adjustments should be done 1/8th of a turn at a time, surprise you didnt feel much difference.

At the end of the day it is a 125 2 stroke, it is never going to have much low end torque. A powervalve adjustment will not give the bike more power just alter the way it is delivered. Just learn to keep it on the pipe and she ll fly!!

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