Seized Engine (I think) on a 2001 WR-250F

Hey guys what's up?  I think I've got a MAJOR problem with my 01 WR-250F and could really use some advice.  

Here is what happened:

A few weeks ago I went out riding for a couple of hours and during that time my bike was running AWESOME! When I was on my way back home I had just turned onto a paved road and was letting it rip, I had shifted into 4th and was just about at full throttle when all of a sudden the engine sputtered twice then totally shut off and the back end locked up (scaring the you know what out of me) and I came skidding to a stop.  I tried to kick it but the kick starter wouldn't budge, so I put it in neutral and pushed it a few miles back home.  Once home I was able to get it to kick over a few times and the bike actually seemed like it was close to starting once, then on the next kick it backfired and the kick starter locked up again.  I haven't touched it since then and was wondering if any of you guys have any thoughts about this. Why would the bike be running so good then all of a sudden have the engine seize up?  How come when the engine cooled off a bit I could kick it a few times? How much do you think it would cost for a mechanic to fix it - rough estimate? Or do you think I could do the repair myself?  About the only thing I've done engine wise was to rebuild the clutch once, but I've got the manual here and am pretty handy when it comes to stuff like this. I know it's about impossible to give much info without actually being here and looking at the problem but if anyone could give me some ideas on what may have happened - a best and worse case scenario, I'd appreciate it.  I just need to have some idea of what I might be looking at because if it's something that has to be done professionally by a mechanic then I'm pretty sure it's going to be big time expensive and that means that my wife is going to kick my butt! Tis the season.

Thanks guys!  

It siezed. When it cooled off, the metal contracted, likely just enough for you to break the piston loose, but the damage was already done.

At mimumum you will need a piston, rings, gaskets, circlips, and piston pin (about $150-200). You will likely need a cylinder (about $200 or so).
If you are lucky your crank survived.  If not, you will be in for a VERY expensive repair job.

Normally the valvetrain survives a siezure, but it should be checked when the engine is apart.

So - my guess is $500 in parts.  If you have a shop do the work, you can count on about $500 or so in labor as well.  
**

Here we go again!

yea, it's done. iv'e just gone through the same thing, except my pistonrod was welded to the crankshaft.an aftermarket crnkshft ass. could cost as low as $250.get the circlips, and a gasket kit. a bike manuel from CLYMER will help you step by step if you do it yourself, don't be afraid! it's only nuts and bolts.  

I wish u luck with ur possible seizure sounds like the exact same thing that hapend to me today on my 2006 yamaha wr250f i was riding mine today at the local dunes it was runin great for about hour and a half then on my way back to my truck to load up all of a sudden it just died back wheel locked up and i couldnt restart it with the electric start or the kick starter seemed to be seized. wen i got it home and partially took it apart i found about 600 dallars in damage plus the labor unless i do it myself, took the head off and found a shattered valve bucket metal pieces from it all over the head and took many things with it unfortunately many head parts for my bike arent sold seperately so i have to buy the hole head for 550 bucks plus bunch of other stuff fortunately i found a yamaha dealer in seattle thatll sell me everything i need at 30% off head alone instead of 550 is now about 360 (these are ruff estimates btw) but it'll save me a lot but i still need to find everything else wrong so its fixed right oh and i need a cam too and mines a 5 valve fyi but anyways i wish u luck i honestly feel your pain did i mention i still owe 3700 bucks on the bike lol  

blysct:
I wish u luck with ur possible seizure sounds like the exact same thing that hapend to me today on my 2006 yamaha wr250f i was riding mine today at the local dunes it was runin great for about hour and a half then on my way back to my truck to load up all of a sudden it just died back wheel locked up and i couldnt restart it with the electric start or the kick starter seemed to be seized. wen i got it home and partially took it apart i found about 600 dallars in damage plus the labor unless i do it myself, took the head off and found a shattered valve bucket metal pieces from it all over the head and took many things with it unfortunately many head parts for my bike arent sold seperately so i have to buy the hole head for 550 bucks plus bunch of other stuff fortunately i found a yamaha dealer in seattle thatll sell me everything i need at 30% off head alone instead of 550 is now about 360 (these are ruff estimates btw) but it'll save me a lot but i still need to find everything else wrong so its fixed right oh and i need a cam too and mines a 5 valve fyi but anyways i wish u luck i honestly feel your pain did i mention i still owe 3700 bucks on the bike lol

Wow,

First welcome, and sorry to hear about your WR.  Thats the one downside to the new 4-strokes; when they let go its ***

If you want to discuss your bikes issues your best bet though is create a new thread so it gets the proper attention and responses.  
.
Dave H 2006 YZ250
(2008 YZ 125 son)