Interesting 06' Problem...Ideas? (Not a Newb)

Ok guys, here is the back story (Kinda Long):

I put both bikes (06' CRF250, 03' CR250) in the back of the truck and went to the track. I got there and remembered I had done EVERYTHING for maintenance on the CRF except the easiest thing and change the filter. I rode it anyways. Got about 10 hard laps in and it felt like I was on the brakes. Made little power and would nose dive in the air and almost die until landing. Felt almost like I had some binding or something in the rear wheel.

Got it back to the truck and pulled the seat to find the filter dirty and drenched in 15-40 and the over flow tube completely full. I had this happen to me a few years ago at a triple header weekend that was dusty as hell(Sounds bad but I usually change filters religiously). I was bummed but had the 2 smoke along so I didn't ruin the weekend.

I got it home cleaned the filter, air box, drained over flow, put it back together and washed it.

Loaded it up the next weekend and took it to the track, it was hard to start but once I got it going it seemed to run fine with the choke as well as idling to the track (I run a higher idle as well). Got it out on the track and it was doing the exact same thing power, felt like I was dragging the back wheel when I got off the gas and would nose dive on jumps just the same. I pulled in immediately knowing something wasn't right somewhere.

Pulled it apart tonight to check the valves and they were a little tight but not excessive. Both Exhausts were at .009" and the Intakes were at .003". Chain tensioner looks to be ok and functioning and the timing looks to still be spot on.

I pulled the carb while I was at it and will clean that tomorrow. Maybe that dirty filter :thumbsup: sucked up some stuff and plugged something. Its the last thing that I can think of for simple stuff.

Its an 06' with an 08' cam and springs and a CP 14:1 Piston.

Any ideas from the moto family?

I also should probably check the plug to see if that oil fouled it out enough to not let it spark under a load while in the throttle

Too Long for people to read? Any Ideas anyone?

Responses are few and far between on the crf250 forum, I know the 250's are not like the 450s and don't have a site glass, but sounds like there might be to much oil in it. I know if I fill my 450 to the full line in the glass it will put oil in my overflow tube, as far as little power that was the airfilter.There is a guy shawn_mc on the 450 forum you might want to ask his advice he is pretty knowledable

When the engine starts carrying on like that it can mean your crank bearings are shot. Take the oil filter cover off and check the filter for brass shavings. I have read this over and over in the forum

Just a thought

did you make sure both ur wheels spin easily and the rear end is straight and tight?

Maybe a clogged carb hose?

I have a 06 and have the same problem cant work at all :thumbsup:

I'm gonna clean the carb up good, pull the filter and take a peak at it. If there is bronze, she is getting retired and parted out. Sadly the day might be here. Thanks for the help, I will report back on my findings. Hopefully it is something simple, I'd like to keep the ol' girl around a bit more. Like a bandaid, sometimes cutting ties quickly is just the best way to do it.


Pulled the filter, cut it up and no Brass from what I can see. Some small AL slivers. Pulling the clutch basket to see if the seal has failed. I needed to inspect the basket anyways. Might just pull the head to inspect while I've got it this far apart.

Thank god for the trusty ol 2-Smoke so I can still ride.

Worst comes to worst I will swap the wheels, pegs, misc and part out the thumper

Where did you end with this?? What,if anything, did you find out in the end??

I've been traveling for work alot and when I have had the chance I have been riding the 2-Stroke. Hope to dig in a bit more this week but it is still at the last post.

Good luck and keep us posted!!

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