1989 XR600r Motor rebuild

I am rebuilding a 1989 XR600r, found a bad rocker and Im not going to take any chances and reolace the cam. What cam do I put in? Happy with stock power but woudnt mind a more aggressive cam if there is no tradeoff in reliability (I know there is always a tradeoff, but something mild the tradeoff is pretty minimal). HRC, WB, Hot Cams?

With the motor apart, anything to replace on the lower end?

Finally, if I feel that I am in over my head, who do I ship the heads to? Who does good work? I want it back to stock specs, nothing wild. I think the cam is all I am going to do unless the piston is shot or the lower bearings are toast.

Depending on the hours, a new cam chain and tensioner might be a good idea.

Look in the crankcase and take a good look at the transmission gears. If you see pitting on the gears it might be time to replace a few.

Measure the ring end gap. The rings usually go before the piston or the bore. Measure everything carefully to be sure the piston and bore are within wear specs. It takes some special tools to measure the bore. Take it to a shop if you don't have them.

I had a couple of valve seats go bad on my 600. I tried the local Honda shop and they couldn't fix it correctly. A few months later I sent the head to XR's Only and they fixed it right. It's been working for a couple years now.

I can't really comment on an aftermarket cam as I still run the stocker. However, a stage 1 cam should be OK. Any stage 2 style cam will result in accelerated valve train wear due to increased lift.

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