Hello and thanks for the replies.

This bearing is supposed to be new, it just looked pretty scrubbed to me. All the other bearings you can tell are new. This one looked suspect though. The PO slid a couple cams in and out and maybe thats where the wear is from. A brand new CC camshaft turns freely, so I guess I'll leave it alone.

I plan on using a high volume oil pump, I was not aware ATV oil had high zinc content. I usually use Valvoline synthetic racing oil and zinc additive, but man, it's pricy. I think the last oil change I did on my 440 with a premium filter was right around $100.00