Time to Split the Cases

[crfjedi393]

My '04 CRF250R has been EXTREMELY reliable. The only engine work I've had done was a top end rebuild by Pro Circuit in early '06. I have checked the valves but haven't needed to re-shim since then. I ride or race pretty much every weekend year round. I've been half expecting a seized crank, a broken rod, or some other major malfunction for the past few months. I decided to bite the bullet and just order a crank, piston and rings, all new bearings and seals, and gaskets. I bought a new cam chain and tensioner last year so I will keep them for now. I've been running some super high rpm's lately in the OCCRA series and am figuring to save myself some money by replacing the main engine components before it's too late. I reckon the regular maintenance has payed off but I don't want to push it.
I'm open to suggestions on anything I'm missing.

[KKXR400R]

I can totally sympathize with you. We are gonna be buying a seperate head for he 250f and slowly build in a 3 month period. We are still waiting for her original head to get back to us from Pro-X but when it does I'm hoping it will be more reliable. Heres a list of what we put on it

Kibblewhite SS Valves
Kibblewhite SS valve spring set
New valve guides
Wiesco Piston and rings
new cam chain and tensioners
Stock top end kit
and theres a stock Honda bearing that Chris ordered....I'm still scratching my head on this one . part #91002-MEB-671

I didn't mean to highjack your thread here.....

-Kevin-

[MotoMan]

Wow man, good luck with the rebuild!!

If you are going to those extents I would go ahead and do new valve seats and a fresh set of valves as well.

[MotoMan]

Nevermind....just re-read and saw your pro circut info.

[crfjedi393]

Originally Posted by MotoMan

Nevermind....just re-read and saw your pro circut info.

No comment.

[Florida 393]

Well, at least I'll know why you won't be calling for a few weeks

Bill

[P1M]

Originally Posted by KKXR400R

I can totally sympathize with you. We are gonna be buying a seperate head for he 250f and slowly build in a 3 month period. We are still waiting for her original head to get back to us from Pro-X but when it does I'm hoping it will be more reliable. Heres a list of what we put on it

Kibblewhite SS Valves
Kibblewhite SS valve spring set
New valve guides
Wiesco Piston and rings
new cam chain and tensioners
Stock top end kit
and theres a stock Honda bearing that Chris ordered....I'm still scratching my head on this one . part #91002-MEB-671

I didn't mean to highjack your thread here.....

-Kevin-

Kevin thats my crank bearing!

Jedi,
My only advise is use factory honda gaskets. They come in kits from Honda for top and bottom end.

[crfjedi393]

Originally Posted by Florida 393

Well, at least I'll know why you won't be calling for a few weeks

A few weeks? This better get done in a couple of days! Got a series to race.

Originally Posted by P1M

Jedi,
My only advise is use factory honda gaskets. They come in kits from Honda for top and bottom end.

Agreed!

[ossagp1]

I dont know if you noticed it or not, but the crfx uses the same second gear as the crf. I think that it would be so easy to make a better cross country bike out of a crf by simply putting in the low gear (mainshaft and countershaft gear) from the crfx. Then you can gear for more top and still have a good low gear if you need it. Just a thought,,since yours is going to be split.

[crfjedi393]

Something to think about. Thanks! It will likely boil down to the green stuff. That sounds like a great idea if I can swing it.

[crfjedi393]

Done splitting. Waiting on gaskets and new piston.




Here's a safety wire job rbm33 came up with to keep the gears in place while we knock out the old bearings.




And here's an '04 piston with lots of hours if anyone cares to look at it.

[char393]

Ack.. nekkid engine!!!



Thanks for the pics and the progress report..keep it coming, I like following threads like this.

[KKXR400R]

That looks like its going to be a project! Good luck with all that. I'm curious if you could post an approximate amount of what this is gonna cost ya, along with the amount of labor. That would be neat for that KB thread for some of the first timers...like me! Thanks for the pics, now I know what to expect next year.

-Kevin-

[Henry]

jedi, how did you get the cases apart?

[Florida 393]

Nice report so far David and great pictures to illustrate the narrative. I want to move this one to the KB when you finish with the rebuild. I am fixing to tackle the cam chain with the post that bsanch did last month on the 426. You guys and gurls do some great technical posts that are really helpful.

Only thing I can offer if you didn't already think of it is seals to go with the bearings.

Bill

[crfjedi393]

I really wasn't doing anything here for the KB forums. It's pretty tough to take pics with messy hands being all by your lonesome. rbm stopped in a couple of times in between jobs and gave me a little guidance. He's a busy man but he has some GREAT tools so I love doing my work at his place.
Henry, as for getting the cases apart........ It's just a matter of backing out a bunch of 8mm bolts and using that orange dead-blow hammer you see in the last pic. If they don't start showing a crack fairly soon, you've missed a bolt somewhere. The oil drain bolt needs to be removed, too.

I'll try to take more detailed pics when it's going back together tomorrow.
New seals are in, Bill.

[ossagp1]

I would say you got your full value from those rings and piston.

[DRGSin393]

Very kewl post Jedi, thanks!

[yz250guy]

Cool. Can't wait to see the pics of it going back together with the new parts! Preventive maintenance is the way to go

[crfjedi393]

Originally Posted by KKXR400R

I'm curious if you could post an approximate amount of what this is gonna cost ya, along with the amount of labor.

I'll do that when I'm done. I'm sure I'll be taking some of the bearings and seals back to my local Honda shop and getting a refund. I don't see any way to get some of the old ones out. But I can tell you this. It's less than $500 as I'm not paying for any labor.

BTW, the piston and gaskets didn't come in today so it looks like tomorrow is the day to get it back together. I need to make sure it's all good before racing this weekend.