Do these cam lobes look okay? 2017 R1200GSA

[akbeemer]

2017 R1200 GSA - 35,7000 miles. Valve clearances have not changed since I checked at 500 miles and now three times thereafter. My last chance to go over the bike before the warranty expires.

How do these look?

Right Intake
IMG-1659.jpg

Right Exhaust
IMG-1662.jpg

Left Intake
IMG-1661.jpg

Left Exhaust
IMG-1660.jpg

[pappy35]

If your dealer is reputable (i.e. you trust them not to screw you) I'd run, not walk, there and show them those pictures. I too would be concerned but if there's no scoring then I'm not sure I'd panic about it (not saying you are panicking, just a figure of speech). Can you feel any scoring or a ledge at either side of the "polished" center section if you run a fingernail across each cam?

[Lee]

Maybe it's just the picture but it looks like there is a definite notch worn into the cam lobe.
I agree, send pictures to the dealer now.

[pappy35]

If you need new one's they are over a grand for all four plus installation labor if you can't do it yourself.

[PoorUB]

They don't look very good to me!

That right intake looks like it has considerable wear, but maybe just the light.

If you run you fingernail across the "bad" spots, do you feel anything? They should be mirrior smooth.

[kevinsclo]

They look scratched?! No oil?


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[akbeemer]

I cannot feel any irregularities or a ledge on any of the lobes. I will send the pictures to my dealer. They have always treated me well. At the very least I will have a record of my concern if it gets worse.

[Lee]

I cannot feel any irregularities or a ledge on any of the lobes. .

I looked at pictures on a couple of my valve checks and I have the same dark line on the edge that makes it look like a ledge. Like yours mine do not have a ledge.
Mine do not have the scratched look so I would still contact the dealer to be safe.

[akbeemer]

They look scratched?! No oil?


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Oil was good. Serviced in accordance with BMW’s schedule using Castrol 5W-40 4T. Normal amount of oil in the valve covers and a good film of oil on the lobes.

[stooie]

Kevin:

Gee, those look pretty bad to me. Just to make sure I'm seeing what I think I'm seeing: Are what appears to me to be circumferential scratches on the lobes truly in the metal? It's not just the oil film giving a funny look, is it?

If the cams really have those line/scratches in the metal I'd be asking for a very thorough explanation from the dealer. The problem with any sort of distress on the surface of cams or gears is that any mark at all causes a stress riser which leads to more distress and wear in the area. Once it gets to a certain level things degrade pretty quickly.

Good luck with it! Please let us know what the dealer has to say.

PS: This seems to be a good argument to be sending oil to a lab for analysis on a regular basis to keep on eye on wear trends.

[Pauls1150]

Typically, the "fingernail" test works OK, but some of those pics show that the scuffing is uneven horizontally across the lobe - That indicates the hardening is wearing off. I'm with Stooie on this one.

[akbeemer]

I have pictures sent to two senior techs at two different dealerships, one I know and the other is a friend of a friend. I already have the opinion of a well respected member of this forum who said they look okay to him. He can identify himself if he wishes. We shall see what the others say.

I appreciate the input of you all and welcome more.

[jandhumphreyme]

I've seen quite a few cam shafts over the years, some discolored, some not, with no discernable pitting or ridges I don't see anything I'd to be too concerned with at this point, certainly worth keeping an eye on. Do you have a dial indicator with .0001 scale? You could spin the cams and see if there are any low spots.

Thanks for posting the photos, very interesting and informative. Please post the tech's opinion when received.

[pappy35]

Given the cost of the parts, I'd take it in to the dealer and ask them to look at and document it.

If, and that's a big IF, they fail sometime in the future, that might help your dealer pitch BMW for good-will coverage. Since the covers are dangling in the the breeze (yay boxer!) it wouldn't cost much, if any, labor and might just come in handy someday in the future. Not knowing if those cams are treated in any way makes it difficult to judge but surface patterns like that look like chrome plating (or other surface hardening coating) that's wearing through. It's good than you can't feel anything but I'd still what an official evaluation.

PS - folks might take issue with me mentioning a specific coating. Yes, I have no idea how they treat those cams for wear resistance, but, then again, unless they work in the factory where they are made, chances are neither do they. So, caveat: This is all conjecture by a well-meaning but semi-informed lot trying to be helpful.

[LFarling]

I have literal looked at over 100 cams and have NEVER seen any with that look.

Conventional wisdom says if you can not feel that with a fingernail it is fine. I guess the first question is how long they been that way? I mean was it opened before and not noticed or seen, or maybe not there, and now at this mileage is?

Me I would close it up and check again in 3K or so. If you can not feel it now or then then just keep a eye on it. If the hardening was coming off you would think you would feel something. Did you get a jewelers loop on it or any kind of magnification?

If you can get a dealer to replace I would do that for sure and with the known issue it may just be a very easy replacement process.