Author Topic: Finned exhaust clamps cleaning up & replating?  (Read 1045 times)

Offline theriddler

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Finned exhaust clamps cleaning up & replating?
« on: September 23, 2018, 09:18:05 PM »
Hi does anyone have any suggestions on how to rejuvenate the finned exhaust clamps? I can get them clean but would then like to get them treated as they seem to be prone to rusting?
John R - '76 CB750F1

Offline AshimotoK0

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #1 on: September 23, 2018, 10:51:58 PM »
You have to remove every trace of chrome/nickel plating by reverse plating in the chroming bath. Then  media blast them, then clean up with a rotary wire brush.

Well that's what two chromers I have used both  told me anyway. Very difficult items to chrome and even originals tend to spot rust very easily.
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Offline RGP750

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #2 on: September 24, 2018, 06:54:27 AM »
The fins were designed originally to be rough as this increases surface area and
 causes turbulence over the surface to dissipate heat.
Back in the 70's when it was 'cool' to polish the fins on heads and barrels bikes frequently seized as they ran too hot .
Yes they don't seen to last very long when replated .
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Offline kevski

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #3 on: September 24, 2018, 10:38:01 AM »
You would be better off sourcing new ones, this would be a cheaper option, they would still end up rusting quite quickly though as the fins shield the recesses during plating and the underlying nickel remains very thin and chrome is not waterproof.

Offline AshimotoK0

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #4 on: September 24, 2018, 10:58:01 AM »
You would be better off sourcing new ones, this would be a cheaper option, they would still end up rusting quite quickly though as the fins shield the recesses during plating and the underlying nickel remains very thin and chrome is not waterproof.

Agree ..it's about fifty quid to get a set of 4 re-chromed.
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline hairygit

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #5 on: September 24, 2018, 11:02:00 AM »
You would be better off sourcing new ones, this would be a cheaper option, they would still end up rusting quite quickly though as the fins shield the recesses during plating and the underlying nickel remains very thin and chrome is not waterproof.

Agree ..it's about fifty quid to get a set of 4 re-chromed.
How about asking Philpotts if they would do them? The hardchrome they use on forks is not quite as shiny as say that on exhaust downpipes/silencers, but it is very hard wearing.

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Offline martin_uk

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #6 on: November 21, 2018, 09:21:44 PM »
I have had them zinc plated or nickel plated which is normally much cheaper than chroming
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Offline Rozabikes Tim

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #7 on: November 21, 2018, 10:27:18 PM »
Just a thought. I had a DOHC CB750  and had the whole motor plastic coated, which included the clamps (similar style). The cases and head were black and the block silver. I had no issues with the finish or engine performance even with a pretty heavily tuned motor. I appreciate this is probably not your answer unless you simply want practicality....

Would the ceramic coatings people use on exhausts work? Lots of colours available.


Tim
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Offline flatfour

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #8 on: November 22, 2018, 08:26:20 AM »
Every couple of years I take the exhaust rings off the bikes and, after masking up the polished areas where the retaining studs pass through, paint them with high temperature aluminium paint. This looks fine (at least to me, much better than rust!) and usually lasts through two riding seasons. The areas that remain polished seem to go quite well with the painted finish.

Offline Spitfire

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #9 on: November 22, 2018, 09:50:50 AM »
I had mine re chromed and to be fair they lasted a lot of years but one went rustier than most, so I bought a new NOS one and it was as bad as the one that I wanted to replace, so I now do the same as flatfour, the rusty parts get a clean up and then the High temp Aluminium paint treatment, this also works on the welds on the header pipes.

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Offline Green1

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #10 on: November 22, 2018, 06:39:14 PM »
Mine have also been painted as rust is inevitable.
I went a slightly different route as I have veriouse differnt rattle cans kicking around for special effects at work.
I treated the rust then painted them with gold rustoleum combicolor and then rustoleum chrome metallic.
They have lasted very well over two years. They have lost there shine but are still looking better then if they were done in VHT paint.
 
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Offline theriddler

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Re: Finned exhaust clamps cleaning up & replating?
« Reply #11 on: December 09, 2018, 01:46:50 PM »
Cleaned mine up & was going to paint them, but took bike out for a ride instead ... oops! Then cleaned down bike & already exhaust  clamps are rusty after a fortnight! :(
I have a spare set which aren't too rusty which I'll paint then swap over ... wonder if exhaust will come off enough to swap over fins clamps without disturbing pipe to collector box &  muffler seals?
« Last Edit: December 09, 2018, 01:50:03 PM by theriddler »
John R - '76 CB750F1

 

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