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Discussion Starter #1
I have read and seen videos that suggests polishing the somewhat course black finish on the cams included on bikes like my 996. The idea is to reduce rocker wear. Is there a general concensous on this?

I have the cams out anyhow for work, and I'd prefer to reduce the amount of times I have chrome peeling off my rockers.

I have never seen a cam on any bike with a finish like I have on my Duck.
 

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The coating on the stock cams is likely to help hold oil or for hardness, there are a few aftermarket cams (ducati performance as well) that are bright and shiny but most have been coated . it may also be a surface hardening process and you would need to be careful not to remove it too much and expose softer steel under the hardened layer. If you are planning on going that far start with a set of performance camshafts and have them DLC coated first.

Either way the rockers were the issue not the camshafts as the early and latest rockers have similar failure rate while 97-98 were the worst with NO change in camshaft coating/surface.
 

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If you remove the nitrite treatment, you will reduce the value. The treatment reduces friction and increases the hardness of the contact surface. I know some look pretty ratty. I've never found any that looked objectionable to me although they do look less that spectacular, but I've heard....

If your's look particularly ratty, offer up some pictures.
 

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Discussion Starter #4
Great advice from everyone as always, thank you. I don't think my cams look any different than the others I have seen.

I haven't inspected all the rockers yet, I will just refresh as needed and carry on with the current cams.
 

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Discussion Starter #5
If you remove the nitrite treatment, you will reduce the value. The treatment reduces friction and increases the hardness of the contact surface. I know some look pretty ratty. I've never found any that looked objectionable to me although they do look less that spectacular, but I've heard....

If your's look particularly ratty, offer up some pictures.
I had time to pull the cams today. I found 3 bad opening rockers. Oddly enough, the rougher the cam surface the better the rocker looked. Once upon a time I was a machinist, and I do have some experience with heat treatment and coatings. I don't recall ever seeing nitrile coating actually create a texture like this.
 

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It may be the pictures but the closing lobes do look like they are textured, that's not normal. The opening lobe being worn as it is was caused by the bad rocker as the edge of the missing chrome wiped off the coating. I have seen cams with a sort of mottled look to them but never a issue caused by them, the other cam in the picture looks more normal from what I can see.

Bottom line if you are concerned at all replace it with a used one as Last I knew they were plentiful and cheap as they do not need replacing very often unless someone does not check rockers and leaves a bad one in there because it is "in spec. " for valve clearance.
 

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Can't really be sure from the pics but they look like they were rusted before they were coated. Can you feel any surface roughness on the unworn part of the closer lobes? If they were rusted, that could eat the chrome face but the rocker wear doesn't look any worse than any of the other flaked rockers I've seen that have been on smooth shiny lobes.
 

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Discussion Starter #11
Can't really be sure from the pics but they look like they were rusted before they were coated. Can you feel any surface roughness on the unworn part of the closer lobes? If they were rusted, that could eat the chrome face but the rocker wear doesn't look any worse than any of the other flaked rockers I've seen that have been on smooth shiny lobes.
They do not appear to have any rust at all from what I see. There is a little texture to some of the lobes, it looks more dramatic in the photos than in real life, but you can definitely feel some texture to the cam lobes.

If I have to replace the cams, is there an upgrade worth doing at this time?

For what it's worth, this motor only has 3500 miles on it...
 

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This was the video I saw of EMSDC that made me actually write this post. I would be very interested to actually hear how his technique held up over time, and what the change in rockwell hardness is before and after plating.
He did a part3 to that video
 

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Discussion Starter #14
I think I will be on the lookout for a spare set of cams off ebay. His polishing did appear to be ok for 12,000 miles but i can see how it would be very difficult to keep a perfectly flat and perpendicular surface polishing by hand.
 
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