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RMX250 Powervalve Change?

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Hi,

I have been looking into changing the powervalves on my '97 RMX250. Zig06 suggested a pair of '95 RM250 Powervalves. Has anyone out there done this change? I have even considered machining a couple of blanks and not running a powervalve at all? Not sure if the bike would be un rideable if I did this though. Anyone got any thought on this?

Any ideas would be greatfully recieved.

Thanks

Jon

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If Zig said it works then Thats good enough for me :banana:

He's owned alot of Suzuki 2Ts including RMXs. I also think he just had to do the same thing to his RMX.

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If Zig said it works then Thats good enough for me :banana:

He's owned alot of Suzuki 2Ts including RMXs. I also think he just had to do the same thing to his RMX.

Ditto.

Why do you want to change them?

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I did this change because when my power valve broke up in my '96 RMX at the end of last year (literally the last ride of the year) I discovered how expensive those little pieces really are. What's even worse is that a previous owner had removed the two smaller slides, so I was running two slides short (I'm sure there's a joke some where in there).

Damage list:

One of the slides in box #3 was broken

Both #8 & #9 were missing

To replace those parts I was looking at about $360.

SU0253_005.gif

It just so happen that I had a complete '94 RM250 cylinder sitting on the shelve, and all of the power valve parts did interchanged. You do have to go with a complete set, it's not just a half RM and half RMX deal. I haven't ridden the bike yet, maybe in a couple of weeks the snow will be low enough to make the trails passable then I'll post a ride report. I did consider using the complete '94 RM250 cylinder but it had a steel liner (my RMX was still plated) and I would need a cylinder head off of a '92 RM250 to get the radiator hose and head stay to work with the RMX setup and the newer o-ring cylinder ~ and that wasn't worth it.

In any case I'm expecting my RMX to still act like an RMX only with a little more top end and a little less low end or mid range. Because even though the power valve has changed I still have the RMX pipe, a wide ratio trans and the heavy RMX flywheel.

in klxman's case you would need to check on your '97 RMX a little bit further because the US models never really changed but the Austrailian and maybe European RMX's did, I just do not remember when (around '97 ??). In any case you would only need to source those parts from a similiar year RM if you wanted to go the same route that I had to go.

Edited by zig06

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Thanks Zig, although the RMX is a 97, the valves look the same as the RM you are talking about so see no reason why the swap should not work? The RM valves are very rare though, I have spoken to effectively @250 breakers and none have the parts. New would be over £400 against about £150 for the standard part. Its just a case of risking the engine chewing another valve!! There is a lot of wear on the one side so was going to get it built up with Aluminium weld then machine it back. I will be interested to hear how you get on Zig.

Regards

Jon

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Ride report!

Yesterday I had Friday off and the trails were calling, so I decided to go for it. Good thing I did because today it's snowing...

Anyways, I took it easy in the morning and broke in the RMX. Made a jetting change and went back out in the afternoon to break in the '08 (another new piston) and to get some real riding time on the RMX. As far as the power valve change in the RMX goes (from a RMX setup to a RM setup) I have mixed feelings about the swap. There's only three real changes that came out of it, one is that it does rev out faster which for the type of riding that I do is fine (mostly deep sandy trails).

Number two change is a downer and that's because with the RMX valve you do have more midrange, so with this change I did lose some midrange. The third change is that because it rev's faster through the RPM range you spend more time in an RPM range that the pipe was not designed for. So it spins up faster to a point where it just doesn't make any more power, just more noise.

Soooo, we have options. If you like and want to keep the RMX's burley midrange then keep it stock. With the RM power valve, I really need to use an RM pipe. So right now I'm looking for a stock '92 RM250 pipe which should directly bolt on. Naturally, that should work great with the RM power valve. Or I could try an FMF Gnarly pipe for a '92 RM250 which should get me back some of my lost mid range.

The best out come that I can see right now would be for me to find a decent stock '92 RM250 pipe and try that. Then I would know which way to go with a new pipe (an FMF Fatty or Gnarly pipe). And that's because a pipe change is still cheaper than a completely new power valve.

So does anyone have a stock '92 RM250 pipe laying around??

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