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Rm 125 Slingshot Explain The Manual Powervalve

4.6K views 1 reply 2 participants last post by  RGrider  
#1 ·
I brought a RM 125 today (old one)
My mate looked at it & said its a very rare 'slingshot' model.

Said the power valve is known as power BAND & you can adjust it manually with a pair of pliers to fully open so its pure fierce rip ya nobleys off powaaahhh or half way or whatever you want.
Can someone explain to me why / how / what is the point in this power band being able to manually adjust?

My CR is an 04 and so i dont know about this type of valve, so i obviously would like to know for my own knowledge & also so i know what to do with the bike as if its as rare as my mate says then it might be worth stripping it naked and restoring every inch of it so its mint.

If anyone knows about these old chesnuts please do bang away about it below!!
And yes i know its classed as super evo class now due to age, but im more interested in if the model is rare or not.
It has a Mikuni TM carb where as the normal RM of the same year has a Keihin Carb.
Also its f**king huge i feel like a kid stood next to it my cr is no where near as tall as it

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#2 ·
That thing on the side of the engine is part of the power valve, it's used to adjust the powerband, but it isn't "a powerband" if that makes sense lol. What it does is as you twist it clockwise it loads up a spring which stops the powervalve opening so early, the more you twist it the later the powervalve opens so you essentially get a broader spread of power and it should be a little more easy to manage depending on the sort of riding you're doing. If you're riding trails you want it opening later so you get more mid range, if you're riding MX you want it open soon as possible to get the most power. Hope that made some sort of sense to you lol.