Is this 256 cam junk... or OK

I just went and dug out my 72 engine stuff to see if I had matching numbers on my head and rocker box. And I do.

So as I was doing that I ran across my 256 cam. I thought I'd bring it in and take a look at it and maybe sell it to fund my project.

To my surprise I find some scratches on one of the lobes. I swear I was very careful removing it and storing it. Could this be engine damage or does it look like I probably did it moving stuff around, or removing the cam.

So. Is it junk or it can be ran.

Looks like it got dinged from something. Since that's in the area of the base circle, it could be polished out and re-used, assuming that it's base and lobe measurements check out. I'd check the rockers too...

TwoMany,

Would that be caused by too tight on the valve clearance, scrubbing oil off the base circle and causing this excessive wear.

Wear is not centered, but to one side, which is strange.

Brian902 said:

TwoMany,

Would that be caused by too tight on the valve clearance, scrubbing oil off the base circle and causing this excessive wear.

Wear is not centered, but to one side, which is strange.

Click to expand...

I don't think it's wear. It's a scratch from mishandling.

I'd run it no problem.

Brian902 said:

...Wear is not centered, but to one side, which is strange.

Click to expand...

Well, I was zooming in on the scratch area, and noticed that the scratch(s) overlap the follower score lines. So, the scratches occurred later.

The biased follower wear pattern on the lobes isn't terribly unusual, but not desired. Properly broke-in, the follower should have established full-width contact. This cam may have a checkered past, mix/matched with other rockers in another engine, or simply rockers reinstalled in different, non-original positions.

Just another subtle mechanic's procedure that sometimes doesn't make it into the hobbyist/enthusiast garage-shop. Doesn't necessarily cause imminent failure, but influences longevity...

Ah, I see the marks you are talking about now. Someone with pliers or some such thing trying to turn over the cam perhaps.

Very fine sand paper and just take the rough edge off and all should be good.

Here is a possible replacement:
http://www.xs650.com/forum/showthread.php?t=38907

Probe ignition system does not require anything of the advance unit or the threads on the right end of the cam. But that means and ignition change, pricey.