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89 Rmx 250 jetting

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So iv read the sticky on jetting and im going to go through that procedure, however i was wondering what size jets to order that would be close to what i need. Iv got an 89 rmx 250 and im on a fresh topend ( re nickasealed) wiseco piston, procircuit expansion pipe and 304 silencer, boyesen power reeds, twin air airfilter with the airbox lid removed, rm 250 head gasket, yamalube 2r 40:1, and i just picked up a keihin pwk 39mm off ebay used for 80 bucks. The pilot in the pwk now is a 58, and the main is a 124. I know the main is way off but im not exactly sure as to about where it would be, so i was wondering what 3 or 4 jets i should order to get me close. Also, is there anything i should do to the pwk like rebuild kit for floats or replace any parts that tend to wear quickly?

Thanks,

Dan

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Actually all new motor as i just rebuilt the bottom end with new crank and all new bearings throughout as well. Probably doesnt matter but thought i would add it.

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My RMX runs the same specs as yours except I run a 38mm PWK air striker

My jetting is

Main 175

Pilot 42

Slide #7

This is in Australia though I think our fuel is a little different to US fuel also I can't remember what needle I ended up with.

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Just found out my pwk has a #6 slide, do you think ill still be able to get it tuned ok? New to the whole jetting thing and still learning.

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#6 slide might make it hard to jet right, you could always try it and see how it goes.

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Ok so getting into this a little bit finally got a good starting point thanks to uncle apolo and Wmc83, (thanks again). I have the screw on top older style pwk so my float height ended up being 16mm. Right now im on the right track but i ran out of jets and all the stores are closed to buy jets from so looks like im done till tuesday. Because i have the screw on top, the stock cable will not work (works for now but cant leave it like that). So anyone know what cable to run and where to get it? Also, any ideas on what needle to run? Mine is not in the greatest conditon and not even for the bike to begin with. Could i run the one from the stock mikuni or is that a no no?

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Yep the round top PWK is the one to get, I used the Mikuni cable on mine it's too long so I made up a 3mm spacer to take up the slack its not ideal as you run the risk of the cable poping out the top of the carb. I tie wired mine with stainless fishing wire to prevent this but a correct cable is the go finding one could be trip and error though.

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