05 crf 450r valve adjustment help

[adambomb777]

I was adjusting my valves for the first time and have now ran into a problem. I put in the new shims, put the cam holder back in, lined up the punch mark on the right crankcase cover, put the lobes facing the rear, put the chain on the sprocket(lining up the permanant marker lines I made on the chain and sprocket) and put the sprocket on while aligning the index marks, put in the the sprocket bolts. I then go to give it a few revolutions with the kick starter and it gets to the point where the lobes are pretty close to touching the valve lifters and it will not go any further. I can back the crankshaft off and try again but it stops at the same point. It seems as if the cam chain is binding, but when i take the cam bolts out and let it rotate without the cam it is fine. When it came to the step of using the special tol on the cam chain tensioner i just took the whole unit off instead, does this matter???? Any suggestions would be greatly appreciated.

[steven_tonne]

Did you turn the adjuster in before installing it back in.

Maybe timing chain is not on the sprocket at the crank ?

steve t.

[504racing]

On the cam chain tensioner you can remove the middle bolt then stick a screwdriver in there and turn it to relieve the tension. Then put a vise grip on the screwdriver to hold it. Or you can remove the two outer bolts and remove the whole unit. It wont hurt a thing. Is there any chance you installed valve shims that are too thick and a valve is hitting the piston?

[skthom2320]

When it came to the step of using the special tol on the cam chain tensioner i just took the whole unit off instead, does this matter????

It matters if you tried to reinstall it without retracting the tensioner. Once you remove it, the tensioner goes out to its fully extended position.

[adambomb777]

I didn't turn the adjuster in before putting it back on, I will try that and see if it helps. Would that cause the cam chain to bind? The shims I put in are thinner so I don't think it should be a problem with the valves hitting the piston. The timing chain is on the crank because if I undo the cam sprocket bolts it will turn freely with the kick starter, just have a problem when I bolt the sprocket to the cam.

[skthom2320]

If you can install the tensioner in the fully extended position then your cam chain is stretched beyond it's service limit and needs replacement.

If you are getting an "interference" when you try to slowly turn the motor over, double-check all your alignments - engine at TDC, cam lobes toward the rear, etc. I vaguely recall this happening to me when I switched cams and it was something very simple - so simple it's slipped my mind!

[voodoolord]

I just did my first valve adjustment on my 04 and ran into a couple of problems, one of which was the same thing your talking about. Im not sure what I did to fix it but I do know that you need to be realy sure that the crank mark is on the money. I noticed that when I was close to the hole looking at the mark it looked like it was lined up but when I moved a little it looked like it was off so I got a flashlight and sat back aways so my eyes werent playing tricks on me and looked straight at the mark. It was off so I fixed it then set the cam gear. Im not sure if thats your problem or not.

[adambomb777]

Thanks for all the help everyone. I got the the punch mark on the crank to line up, the cam sprocket mark to line up, the lobes towards the rear, and it turns without any binding. I have one more question though, the mark I made on the chain and the sprocket before I disassembled I cannot get to line up??? If I do line up the marks I made, the crank punch mark and the cam sprocket mark will never line up. Is this a problem? Is it possible the chain moved a few teeth on the sprocket on the crank?

[biznet1]

It sounds like your chain moved on the crank, or you've rotated the cam gear 180 (used opposing bolt holes, unless it's pressed on the cam). If this is the case, then you'll have to disregard the marks and use your factory marks for TDC and the cam gear. If you have any doubt, the same applies. Make sure you're TDC, the cam lobes are facing rear, and make sure your factory cam marks are parrallel to the head face.

[adambomb777]

I made a mark on one side of the cam sprocket and the side it bolted to on the cam so I know that it hasn't been turned 180. I was thinking the same thing about the cam chain moving, because for awhile it was binding and that was my original problem. Every thing seems to be okay now, just have to throw it together.

[voodoolord]

Im glad it worked out for you, now make sure you set your decompressor gap correctly before you put the bike together. I put it all back together and the tank on and realized I didnt set the decomp, so I opened it back up and promptly set the decompressor wrong . I couldnt figure out why the bike was back firing and idling funny. It turned out that I set the decompressor to .14 instead of adding that to my valve gap and setting it to around .64. Im just glad I got it figured out.