Seized intake cam on 06 yz 450

Hey guys any input greatly appreciated im familiar with the yz 4strokes top ends but when it comes to the bottoms is where I find it difficult my question is with the intake cam seizing do I need to split the cases and check the crank the bike had 131 hrs on it surprisingly I did usual inspection no up and down free play on the crank no piston free play I haven't drained the oil yet to view the oil screen . I'm replacing the head cylinder piston cams chain pretty much the whole top end basically am I in the clear from splitting the cases thanks you guys for all the input

You normally wouldn't need to do anything with the crank as a result of the intake seizure unless there was significant contact between the piston and valves that would make you suspect damage to the rod or big end bearing. Have the head repaired, replace the chain and tensioner, and carry on.

Yeah I didn't see any marks on the top of the piston I need a new head I don't know if any machine shop can redo the journals for the cams also I'm getting the cylinder works big bore kit should the stock crank be ok for it thanks gray for your input

I had the same thing happen on a buddies 06 YZ450 so I took the head to Engine Dynamics in Petaluma, Ca (707)763-7519 and they recut the cam journals. I had the head back by the end of the week and paid $90. His web site is enginedynamics.com. Hope this helps.

I had the same thing happen on a buddies 06 YZ450 so I took the head to Engine Dynamics in Petaluma, Ca (707)763-7519 and they recut the cam journals. I had the head back by the end of the week and paid $90. His web site is enginedynamics.com. Hope this helps.

Engine Dynamics can fix your head way cheaper than you can buy one for.

Ok thanks guys I'll call them hey do you think I need a different crank for the big bore I'm getting

An '06 with 130 hours! That is pretty low.

What causes the cam to seize? those journals should be getting plenty of oil. Bad bearing?

When i took the head apart it had oil in the head I think he didn't tork the cam cap and the cam shifted and scared the inside of the head I'll take pics of it and post it on here

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