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02 cr250 bottom end

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Well, ive got an 02 cr250 that i will be riding mostly in the woods. After buying the bike, i read this was one of the worst low end/lug years for the cr. Too late. Anywho, i have added a 13oz FWW, and a few other odds and ends. I would like to slow this thing down a bit. Give it some more bottom end. Im not affraid of the bike, cause i use to race one years ago(mx). Just need to make it better for the woods. A shop owner suggested getting a head off of e-bay, and boring it out, or buying a big bore kit. Thus, adding cc's to help the low end, and actually smoothing out the power. Another thing i have considered is buying a pwk 38 airstriker carb. Anybody have any experience with any of this? Thanx.

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The 02 CR 250 actually has a very strong bottom end even more than the YZ of similar years which most people claim has great bottom end. The lack of a hit in the power band makes the bike feel weak. To a normal rider, uncontrollable power makes a bike feel fast. The 02 CR was one of the fastest bikes on the track, in the woods, and on the dyno but it had controllable power which is what the novice riders are complaining about.

Of course, it's still pretty twitchy being an MX bike. The absolute first thing I would do for any woods bike is to install a set of steel clutch plates. Then, set your gearing up to give you the bottom end you want. Dial in the suspension. Maybe drop to an 18 inch rim. Then, if the bike is still too snappy for tight trails, throw some flywheel weight at it. Staged reeds also help.

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I added a 50t rear sprocket & a set of vforce reeds & jetted it. Those mods alone made a big difference. In your case for woods riding you might consider going to a 51t & a Boyesen rad valve. The rad valve will give you better throttle response over the vforce. You can also install a jd kit if you go with the mukini. The kit cleans up the jetting & makes leanier power over the mukini needles.

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I have an 03 that is a great woods bike with just bolt on parts...ya I wish I had a 6 speed trans but that's my only complaint.

I have ridden a 450-x, 250-x, converted crf 250-r, ktm 300-xcw, wr-250 and a kdx 200 on the same trail system and the CR is still my favorite and most fun to ride.

The flywheel is a must, try a boyesen or V-force cage, a Moose reed spacer, Gnarly pipe and a 50-t sprocket.

I have a 36mm airstriker carb that I think helped gain a little more bottom and toned down the hit even more and I also run a trials tire.

Suspension mods are also a must for anything more then jeep trails, far too harsh for roots and rocks.

I don't think a bore kit is a bad idea, I too thought about one but after getting some seat time I don't feel the need...I already have more than enough power, it lugs just fine and when things get slick and greasy the mildness down low allows the bikte to hook up better, I just have to finess the clutch and throttle once in a while.

Get it set up right and you'll love it!

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