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Chrome vs. Electroless nickel plate my motorcycle exhaust pipes?

Q. I am a machinist by trade and also own home hobby machine shop. I am currently building a custom motorcycle for the challenge.

My question is:
If I were to electroless nickel plate my exhaust pipes (1010 mild steel) to a .0003" thickness, will they resist corrosion over the long haul? I know that they would definitely discolor from the heat, but will this heat remove or shorten the life of the corrosion resistance? I am also wanting to use this on other parts of the bike as well instead of chroming. Is this a good alternative to chroming?

Any thoughts are appreciated!

Bill Norton
Hobbyist - Scottsburg, Indiana, USA
2004

A. One trick, although hard to implement, is use double-wall exhaust pipes. I've seen this on a few Hondas. It helps but will still burn off the chrome if you do a long engine-running tune-up session without some big fans blowing on the pipes.

Tom Gallant
- Long Beach, California, USA
2004

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Chrome Plating motorcycle exhaust

Q. I recently purchased an '86 Suzuki VS 700. The previous owner modified the set of exhaust pipes on this bike. He welded a small piece of pipe (about 1" long) to the exhaust pipes where the flange is, so they would bolt up using the original exhaust flange. He did this I believe because these pipes did not belong on this bike. So what I have is: A small piece of pipe that is welded between the exhaust pipe, and where the flange is. He did a very good job, but the small piece of pipe he welded in is rusting, and it is a smaller diameter than what the pipes he welded to are. He did this, so both pipes are on the right hand side of the bike. I like the looks of how he did it, I just don't like the look of the piece he welded in, rusting, and being a smaller diameter. I know my explanation makes it sound complicated, but a professional could cut out/modify the small pieces, and then re-chrome them, and they would look like new. The rest of the pipes, excluding the welded in pieces look like new, except for some bluing taking place. I would like the problem fixed instead of purchasing a new set, but is the process I just explained more expensive than purchasing a new set?

Thank you,

Don Perkins
Hobbyist - Hutchinson, Kansas, USA
2005

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Q. I'm interested in getting a motorcycle exhaust copper plated. Exhaust temperatures usually reach 400-450° F. How will these temperatures affect the plating?

Thanks, Dave

David Mucci
- Chicago, Illinois, US
May 10, 2012

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Q. Is yellow/gold zinc plating a viable option? I've been told it has good corrosion resistance properties but wondering how it holds up to heat. I'm looking for interesting color/finish options for the exhaust.

Thanks,
Dave

David Mucci
- Chicago, Illinois, US
May 14, 2012

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Q. Does cadmium plating hold up to heat any better then zinc? I know this is used on a lot of automotive parts.

I have some samples of nickel plated steel I'm going to test under flame to see if they golden at all.

Thanks for the help.

David Mucci
- Chicago, Illinois, US
May 17, 2012

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Fresh Chrome on Motorcycle Exhaust + Heat = Instant Pitting?

September 16, 2019

Q. Hello,
I've just finished building a completely custom 1958 Triumph 650 motorcycle. For exhaust, I started with an off the shelf set of chrome pipes, then cut and welded them to my style. I brought them (and many other parts) to a local chrome shop, and a few weeks & $$$$$ later, all the parts came back looking shiny and new.
It took a couple of months since then to finish the bike, and everything remained indoors in a climate controlled atmosphere while I finished the build.
It came out stunning, and I took it for it's maiden voyage yesterday (3 miles) to begin breaking in the freshly rebuilt engine. Every part of the bike was reset to as new or better.

     

After my 3 mile ride, I noticed the left pipe turned gold/yellow at the head, and was many many little pits along the bend of the pipe. The pits almost pattern in striations. The right side pipe did not discolor, but is also showing pitting forming in these odd line patterns. Very small, but visible, and tangible.

I expect the discoloration (eventually), but am really surprised at how quickly at happened, and am totally baffled about the pitting! The bike did not sit and idle ever, though a new engine will tend to run hot, and she did get hot (not too hot, just hot).

I'm wondering if there could be anything from the chroming process that has allowed this defect to form so quickly?

Many thanks

Bob Holmes
Hobbyist/custom builder - Clinton, Massachusetts USA

Ed. note: Sorry, this RFQ is old & outdated, so contact info is no longer available. However, if you feel that something technical should be said in reply, please post it; no public commercial suggestions please ( huh? why?)

A. Hi Bob. It doesn't look like "pitting" to me, it looks like "blistering" -- the chrome (or more likely the nickel) isn't adhering to the substrate. If I'm right those blisters will grow and break off. Do you know whether the pipes are steel vs. stainless steel?

I doubt that anyone will want to take part in a contract dispute based on hearing one side of the story and looking at pictures, but I think they'll get worse quickly; so if the plating did indeed cost $$$$$ you might want to retain a lawyer of plating consultant. Good luck.

Regards,

Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 2019

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Durable chrome plating for a 2 stroke exhaust?

December 29, 2019

Q. Hi, so around 2 years ago I had my 2 stroke motorcycle exhaust chrome plated, back then I didn't look into which process he used, but it has started peeling off now and I am looking to get it re-plated again.

Going through your extremely extensive and helpful forum, I have learnt about zinc-nickel plating, cadmium plating, electroless nickel and all varieties of platings available for different applications.

I just wanted a confirmation on which option might be best for me, my new plater is insistent on a copper base for 'buffing and to promote adhesion to the chrome', but I read a few threads over here that recommended against a copper base plate as "The heat will tarnish the plating as the copper migrates" etc. I have tried to come up with a couple of options from going through this forum, could you recommend which one is best for a motorcycle exhaust/header:

(1) copper-nickel-chrome
(2) electroless nickel then chrome (is it possible)
(3) non-brightened nickel-chrome

I know I might be wrong on all three, could you recommend what type of chrome plating is best for me since this is a relatively high temperature application, I just want this to be the last time for me to worry about the chrome on the exhaust as it's kind of held me back from putting the vehicle into vintage motorcycle shows as I don't want people to see the peeling chrome. I would highly appreciate anyone who could help me with this.
Thank you (sorry for the long post)

Charan Venkatesh
Restorer, Hobbyist. - Bangalore, Karnataka, India

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Ed. note: Some fairly similar threads readers might be interested in include:
Topic 14857, "Prevent or remove blue discoloration from chrome motorcycle exhaust?"
Topic 37758, "Why Chrome plate Stainless Steel Motorcycle Exhaust Pipes?"