250 2t question

Hey guys.

As some of you might know I have a 07 kx 250. The previous owner had a 168 main jet in it when it is 160 stuck so it was obviously fouling plugs and was gunked up. First thing I did was clean up then cylinder and rejetted it. It fixed the bike for the most part but the power valve leaks oil out of the breather and im curious if this is normal as i dont recall any other of my two strokes doing this. Now there is no spooge coming out of the muffler and aside from me busting it, the packing is fine. Now I had the pipe and silencer welded back up with new backing and now it sounds a million times better. The bike has oil dripping from the breather all over the garage and it is annoying and I would just like to know if its normal. The bike runs fine aside from that.

Normal. Both our 125 & 250 drip a little. What's your riding level? on the pipe all the time or up & down? When I ride, it spooges a lot. When my son rides, its clean.

Normal. Both our 125 & 250 drip a little. What's your riding level? on the pipe all the time or up & down? When I ride, it spooges a lot. When my son rides, its clean.

Cool thanks a lot. I was just curious because it makes a mess in the garage but i have no spooge at all coming out of the muffler and i dont recall my 125 and my older 250 doing that. My riding level is A. I am a aspiring pro national rider, well trying still gotta get the license and move up to that level, and its mx so the bike is on the pipe most the time, warm up and pit riding its lugging.

Edited by Ringo25

Did your older bikes have the breather vent tube? I have a 2005 KX125 and a 2005 KX250. Both have the tube, but none of my KDX's do.

My 250 is not jetted perfecty, and the only time I am really on the pipe is when my bike low-sides to the left and I high side to the right. :)

I only recently purchased the KX125 and have not ridden it enough to see the tube leak. My 250 does leak some. After putting it on the stand in the garage, I just fold a paper towel in half, then half again and wrap it around the end of the tube. I call it a diaper.

An apparent second use for the tube is an exhaust pipe. I once forgot to pull the silencer plug and started the KX250. It was REALLY smoking out of the vent tube!

Is there any advantage to adding a vent to a bike (like a KDX)? I was wondering if that would help keep the power valve cleaner since the excess oil could drain.

Ringo, need a name. I always cheer for the privateers. I hate all the big money, sponsored riders. Even more in the Amateur world, it is off the leash.

They're spoiled. During my 2 chances with the Pros, Bob Hannah, Rick Johnson, David Bailey, etc showed up in box vans with themselves and their mechanic. I found out how fast (slow) I really was.

If you're not on twostrokemotocross.com yet. Get on there. They try support any 2T riding pro.

Thanks for the replies and am glad to know its normal. My yz 125 did have a vent hose but the 04 cr 250 had the electronic powervalve which did not have it from the older pictures i have of it.

And to sappers: my names Ryan Petschauer ( pronounced Pet"shower") Plan on trying to make Lorettas this year and see how that goes. I know ill be showing up with my pickup truck and my bike at the races though. Im sure ill be part of the few like that there.

Good luck, ride hard, stay healthy. I'll be looking for your name in the regional results too. Tear 'em up!

BTW, what classes? You said your an A rider so that puts you out of the 2 stroke class.

Edited by SAPPERS

The breather tube is a pain in the ass. My 125 doesn't drip that bad but my 250 did. I was going to make a small catch can for it. Just a metal tube strapped to the frame, the cap would have 2 ports, one for the current breather tube and one with a 'J' shaped vent tube. You can just bend up the vent on the case to protect your floor.

Lots of bikes have them, Kaw started using them on either the 03 or 04 KX250 from the front/top main valve cover.

Edited by Jeekinz

Good luck with getting to LL's!!

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