Should i replace a piece, or all of it?

So i recently adjusted my 2006 yz450f valves and after getting everything back together, the bike ran great for about 5 minutes. Then it died, OH NO!!! Sure enough took it back apart and it had skipped 2 teeth on the intake cam. I examined the cam and it showed 2 thin lines of the blue metallic "i just got really hot color." I think i put the cam caps on to tight? There is some minor scarring on the cam too. Needless to say i ordered a new one, but should i get a new chain and more? a new tensioner as well? Thanks guys, help the newby TT Guy!!!

I think i put the cam caps on to tight? !

damn dude, BUY A TORQUE WRENCH!!!

I believe they are supposed to float on a very very thin layer of oil, thats why the proper torque for that part is very very imporant, too tight or too loose and it could cause damage.

Your tensioner should be fine, but I would get a new cam chain...it's cheap anyway. When you're working on internal engine components it really is important to use the proper torque settings, because even if you are a little bit off in there, the results could be disastrous.

Were you sure to pre-lube all the moving parts so they weren't put together dry? And yes, proper torque is best.

Being that it skipped time I'd say a new chain would be a must. I'd make sure the tensioner is up to snuff also.

Once you get the new cam, you can run a clearance check on it (see the manual). You more than likely distorted the bore in the cap/head, and will need to have that fixed.

And yes, always replace the timing chain and tensioner whenever there's been any sort of a skipping incident.

thanks for replying guys. Yeah my torque wrench was an hour away, and i thought hey ill just snug and a lil 1/4 turn more. found out its something nuts like 88 inch/lbs!!! that nothing! so if i replace the chain, whats the best way to go about getting to that bottom gear? pull the flywheel?

Ah ok. that makes sense. thanks for the help guys

Check out the sticky threads on the Yamaha YZ450F form. Lot of good info that will help you. :banana:

thanks for replying guys. Yeah my torque wrench was an hour away, and i thought hey ill just snug and a lil 1/4 turn more. found out its something nuts like 88 inch/lbs!!! that nothing! so if i replace the chain, whats the best way to go about getting to that bottom gear? pull the flywheel?

You need to pull the flywheel and remove the cam chain guide behind the flywheel, then you can just pull the chain out (assuming you have the chain off of the cams already).

found out its something nuts like 88 inch/lbs!!! that nothing!
87, and that's too much. IMO. I use 75 in/lb.

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