In the first pic there is scuffing where the outer race of the cam bearing sits. Is this normal?

In the next two pics the one exhaust valve looks much cleaner. Any reason for that?

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And what's this little guy for? (the one with the blue dot)

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Why did you take it apart? Vintage Bob

Interesting scuff pattern. Almost looks like it goes up, loops and starts back down. I once tore down an aircraft engine that had spun a cam bearing; much much more damage than your scuff. So I guess I'm really just typing and not answering any question... Maybe bearing was installed with some trash under it??

Bob, it's a 250f, it's always apart. Seriously, it's due for rings and the stock pancake showed a little skirt wear so I was interested to have a look. And it's super crappy weather here so I stuck her in the basement for a good once over. Got any tips for suspension fluid change?

2stroker, it's a roller bearing. The outer race is clamped by caps. I would say the outer race was spun for sure. Maybe cold start issue? We do run them a few times over the winter but I usually run 0w40. The cap bolts were reasonably tight coming apart. The cam looks great, no scuffing inside the inner race of the bearing.

Bob, it's a 250f, it's always apart. Seriously, it's due for rings and the stock pancake showed a little skirt wear so I was interested to have a look. And it's super crappy weather here so I stuck her in the basement for a good once over. Got any tips for suspension fluid change?

2stroker, it's a roller bearing. The outer race is clamped by caps. I would say the outer race was spun for sure. Maybe cold start issue? We do run them a few times over the winter (20*) but I usually run 0w40. The cap bolts were reasonably tight coming apart. The cam looks great, no scuffing inside the inner race of the bearing.

Joe - Take a close look at the valve seat contact area and you'll likely see the reason for the difference in the exhaust valve deposits and coloring.

Uh oh, you think the seat is burnt? I'll pop the valves out today and have a look.

Rich, any thoughts on that scoring?

If it was not for the valves, I thought it was a 2 stroke. Rich, oil, coolant or man you are getting some bad fuel. The loose seat makes for a really crappy burn. New valves, recut the seats, you got the lap and run deal. Do you know for a fact the "scoring" was not there before? If the cam is not scored, burnt, then the "scoring" in the race could be there to begin with. The marks could be from the original machining, the shiny is the worn area. Measure the id. No skirt pics? How about side to side, small end of the rod bore? How are the thrust washer clearances? Vintage Bob