cam lobe scratches

[Guest]

camlobe2.jpg

#3 exhaust cam lobe is scratched. There is signs of scratching on the shim as well. The scratch on the side of the lobe fingernail will actually stop in. Thoughts ?

[GregT]

Don't worry about it. There's still plenty of rubbing area. Flip the shim to present a fresh good face to the cam and screw it back together.

[60ratrod]

Probably from someone not using the right tool on the shims. It should polish itself smooth again

[BillH]

One more question - I have seen a couple of notes about installing the half moon rubber oil seals on the ends of the cam backwards to "help reduce" cam walk. Is there any merits to this ? And if you do, what prevents the notches on the end of the cams from shredding the rubber and having rubber bits in your valve train area. Thanks

[AMK]

One more question - I have seen a couple of notes about installing the half moon rubber oil seals on the ends of the cam backwards to "help reduce" cam walk. Is there any merits to this ? And if you do, what prevents the notches on the end of the cams from shredding the rubber and having rubber bits in your valve train area. Thanks

I have cam walk on my '82 and had it on my '82 850, it was occasional and I just ignored it.
Its harmless and it grew on me. Which means it sucks but I got used to it.
I liked the lip of the half moons inside to help keep from leaking and to keep from coming out but I never figured out what keeps them from going in

[BillH]

Thanks Alan
I had what was cam walk noise as well. Last year it was intermittent but this year it has gotten worse. It is all the time now, cold engine, hot engine, leaning, parking it on center stand doesn't matter and it's pretty loud. Yes it goes away after 2K rpm. So my thinking was to try some of the less expensive things a couple of folks had mentioned, like shim buckets, and turning the rubber end caps backward. I have seen the paper on the machining the head and half moon spacers to remedy the cam walk. I would have to take it somewhere for that to be done. Not sure if all the work I'm doing will help but I did want to try. Learning experience anyway.

[AMK]

Oh yeah, if it were constant on mine that would bug me.

[jsandidge]

One more question - I have seen a couple of notes about installing the half moon rubber oil seals on the ends of the cam backwards to "help reduce" cam walk. Is there any merits to this ? And if you do, what prevents the notches on the end of the cams from shredding the rubber and having rubber bits in your valve train area. Thanks

Boy, I'd really like to hear from some people that have tried this. I've shied away from doing it because I'm worried about rubber bits too.

[Dogma]

The manufacturing tolerances are loose enough that the half moons may or may not fit in backwards. On one side of my head, they won't go in backwards. I don't do this for the cam walk though. Intuitively, it seems less likely to leak.

Edit: Oh yes, the cam lobe. You'll notice the scratches are in an area where you can still see the original grind on the cam. It still has clearance on that part of the cam. So, the scratches won't hurt just make sure there's no raised material or a burr ready to fall off.

[BillH]

Update - so I have everything back together and have started it. The knocking noise is gone, well at least for now. YAH !! I think the carbs need tweaking again. So maybe all those little things helped. I hope to ride to ride it some this coming week.