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Cylinder head cover discoloration - Printable Version

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+--- Thread: Cylinder head cover discoloration (/showthread.php?tid=5504)

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Cylinder head cover discoloration - LongRanger_imp - 08-21-2016

Have you guys come across this before? This cover has turned a nice copper color. I haven't seen this condition on any other CB's. I'm guessing it's heat-related but the bike runs great. Bike has about 12k miles.

[url=http://s1285.photobucket.com/user/ericlevy/media/Mobile%20Uploads/197AEEC8-1256-405B-B31D-7F74E2F86847_zps34mw0lwf.jpg.html][Image: c84f91a20a5a5e7df3b20c32428a0dee.jpg]

RE: Cylinder head cover discoloration - Lord Popgun - 08-21-2016

Mine still look like new. How does your other one look?

RE: Cylinder head cover discoloration - Ulvetanna_imp - 08-21-2016

That cover has a different coating than the valve cover, is all.

RE: Cylinder head cover discoloration - postoak_imp - 08-21-2016

Huh, I thought that was all one piece, but according to this diagram, that is a reed valve cover that screws on to the cam cover.

http://www.partzilla.com/parts/search/Honda/Motorcycle/2013/CB1100+AC/CYLINDER+HEAD+COVER/parts.html

Have you tried some polish on it to see if that returns it to the original color?

RE: Cylinder head cover discoloration - Lord Popgun - 08-21-2016

Covers are for the PAIR valves.

RE: Cylinder head cover discoloration - Ulvetanna_imp - 08-21-2016

On my bike, 2013 standard non-ABS, that little PAIR valve cover is painted a silver metallic and has not yellowed at all. I do believe some changes were made in 2014 to finish items and other details.

RE: Cylinder head cover discoloration - LongRanger_imp - 08-22-2016

Thanks everyone. I've not bothered trying to polish it out, and the one on the other side is fine. Just looking to the forum collective to see if it's unique to my bike.

RE: Cylinder head cover discoloration - BayAreaRick_imp - 08-22-2016

^^^
Kind of like a 'birth-mark'??? Confused

RE: Cylinder head cover discoloration - Gumby 1100_imp - 08-22-2016

(08-22-2016, 12:31 AM)LongRanger_imp Wrote: Thanks everyone. I've not bothered trying to polish it out, and the one on the other side is fine. Just looking to the forum collective to see if it's unique to my bike.

I don't think that you could polish it out anyway as it likely has a clear coat over the polished/anodized aluminum. You'd have to take it down to bare metal and then it might darken later anyway.

I was just wondering if those Reed Valve covers had ever been removed on your bike such as during a valve adjustment/inspection. If the reed valve was not replaced properly or was leaking, it may be possible for hot exaust gasses to travel the wrong way and heat up the cover.

RE: Cylinder head cover discoloration - Ulvetanna_imp - 08-22-2016

(08-22-2016, 02:00 AM)Gumby 1100_imp Wrote:
(08-22-2016, 12:31 AM)LongRanger_imp Wrote: Thanks everyone. I've not bothered trying to polish it out, and the one on the other side is fine. Just looking to the forum collective to see if it's unique to my bike.

I don't think that you could polish it out anyway as it likely has a clear coat over the polished/anodized aluminum. You'd have to take it down to bare metal and then it might darken later anyway.

I was just wondering if those Reed Valve covers had ever been removed on your bike such as during a valve adjustment/inspection. If the reed valve was not replaced properly or was leaking, it may be possible for hot exaust gasses to travel the wrong way and heat up the cover.

I don't think that you could polish it out anyway as it likely has a clear coat over the polished/anodized aluminum. You'd have to take it down to bare metal and then it might darken later anyway.

I was just wondering if those Reed Valve covers had ever been removed on your bike such as during a valve adjustment/inspection. If the reed valve was not replaced properly or was leaking, it may be possible for hot exaust gasses to travel the wrong way and heat up the cover. Yes to all the above.