[riosmark458]

So i recently bought a 2004 crf250r for 1700. The guy who i bought it from said that he had just done a valve adjustment and was selling because he was moving up north. i live in Fresno Ca.
The bike started up nice in about 2 kicks so that convinced me that it was in good condition. The only problem i encountered was that it had idel issues everything else ran superb. Yesterday i was riding about 10 mph and out of no where i heard a clicking and clacking noise then the bike stalled. When i went to kick start it, it was completely stuck. i read online and i guess its called engine seize. MY QUESTION IS, HOW DO I TAKE OFF THE TOP END SO THAT I CAN INSPECT IT AND SEE WHAT HAPPEND. ALSO HOW DO I REMOVE THE CAMS IF THE CRANKSHAFT IS STUCK. I would really appreciate any real help that you guys can provide me with.

[dirtae]

You came to the right place man. Thats the risk you run when buying used. I've had it happen to me. If you look at the top of this website, look under 'COMMUNITY" in the Navigation bar. Go to how-to articles. There is a how to on checking valves, doing a top end etc. Read those over, you will get a great idea of what your in for and step by step help with pictures.

How exactly was the bike idling, you said it had problems idling? was it noisy, or just struggling to idle. Is it still seized after cooling down?

[crfsonly]

welcome to CRF's Only. here's the how-to link dirtae mentioned:

http://www.crfsonly.com/howto/honda-crf ... emoval.php

let us know what you find.

ken

[riosmark458]

thank you for taking the time man. YES buying used is a huge gamble. As for the ideling it wasn't noisy or any kind of clicking it was just struggling but it would stay on. the last ride when it happend, it wouldnt stay on i had to give it throttle. Im new to motox and this is my first bike and i bought it on my own therefore im really bummed out.

[riosmark458]

and yes i just checked to see if it would crank but nope nothing at all it wont budge. im guessing this is worse off right?

[crfsonly]

you won't know how bad it is until you pull the head. hopefully there's minimal damage.

[dirtae]

^^^ yup, pull the head. take pictures and post them.

[riosmark458]

THANKS GUYS. It is about 2 a.m and i just got the head off thanks to the how-to posts. I will be posting pictures tomorrow a.s.a.p. I hope to keep this thread alive with the help of all of you.

[crfsonly]

good job! hopefully minimal damage.

[riosmark458]

OK if i can get these pictures on hear you will see the buckets of the intake valves; the one on the right seems to be jammed in real good i have not tried with pliers yet to get it out.
The left one i was able to pull out relatively easy.

The Cam Shaft seems to be in good condition except for the right side also, the lobe seems charred and warped and flattened.

The little bolt looking part is the cam chain tension er. I was just wondering if yall would recommend me replacing that and if i really need to. The only thing that is wrong with it is the loose-metal piece got pried up and sort of broke.

The bottom part of the valves seem ok except for the 'right' intake valve is stuck open and i'm guessing its due to the 'valve bucket' being stuck?

The top portion of the cylinder doesn't have any scratches or grinds so im guessing the piston rings didn't corrode? And the piston itself seems fine except for the 'right side where the intake valve' sits it seems like it hit hard and indented the metal.

[/img]SORRY FOR SUCH A LONG REPORT.
SO I TOOK THE HEAD CAM AND TENSIONER TO MY LOCAL CYCLE SHOP AND THEY SAID THE HEAD WAS JUNK BECAUSE MOST LIKLEY THE RIGHT BUCKET DAMAGED THE HOLE IT SITS IN. ALSO THAT THE CAMSHAFT WAS CRAP BECAUSE OF THE LOBE. AND THAT THE TENSION ER I SHOULD REPLACE WHILE IM AT IT.

I know mechanics will sometimes say your parts are not salvageable so that they can sell you parts and also get work out of it so i just want more advice and i will also be taking the head to other shops.

That being said, im thinking of splitting the bottom end of the engine to see if any bearings gave out due to the starvation of oil but i dont see a how-to article about splitting the bottom end??

[b]ANY HELP IS APPRECIATED.

[riosmark458]

[riosmark458]

PICTURES ARE UP!

[crfsonly]

i too would recommend replacing the head, valves, shim buckets, cam, cam chain, cam chain tensioner and piston. you will need to make sure the bottom end isn't also damaged. you'll need to inspect the entire cam chain tensioner assembly to make sure there's no damage to other components. also inspect the rocker arm assembly. it's unlikely this was damaged but it should be inspected carefully. the roller should spin true and freely. the rocker pivot pin should be true/unbent. the rocker arms unbent. if you are looking for a source for these parts check out our OEM parts website at www.yeltrik.com. in crfsonly.com we have assembled heads with valves installed with CNC improved valve seats and port bowls. let us know if we can help answer any questions about your rebuild.

ken

[ferguscawley]

I agree with Ken 100% here.

Some questions - was there oil in the bike ? What condition was the oil filter in ?
Was there any coolant in the bike ?

[Hondacrfrider]

was the air filter in good shape? (clean and properly installed) and did you ride though deep water?