BMW R1200RT/R1250RT Forum

Thank you for your reply Chris, at the same time, I asked a fellow motorcyclist who is also a metallurgist the same question, this was his take on it.

"The oxide scale (the discoloured layer) that is formed on your exhaust manifold is Chromium oxide, mainly - Cr2O3 with its thickness growing gradually with temperature cycles until spallation."

It's chemistry and not a lot you can do about it. Modern motorcycle engines are set to run lean to meet emission regulations. Lean = hot, I've had my 2012 Camhead re-mapped by Hilltop Motorcycles. The air/fuel ratio is now likely to be richer & slightly cooler running. Certainly not sufficient to prevent discolouring but I do think that it's progress is reduced slightly. When I fire the bike up, I'll keep an eye on how the discolouration develops. Long term, I do think that ceramic coating with Cermakrome is the answer for me.

As you say, double wall pipes is the way to go, my 1980 Yamaha XJ650 (like the one pictured) has 30 year old header pipes on it.

David. wrote:When I fire the bike up, I'll keep an eye on how the discolouration develops. Long term, I do think that ceramic coating with Cermakrome is the answer for me.

Having started the bike up today, even only at idle, the header pipes were seen to discolour in front of my eyes.

Think I'll be looking at Cermakrome again this winter.

This guy is using Autosol Bluing Remover on a GS, https://www.youtube.com/watch?v=lJBlMFUQmFE

Even better results using Blue Away and #0000 Steel Wool.

Wow, that's really nice. I'll look for some of that stuff., thanks.

How long does it last?

The above photo was taken from this thread found posted on the BMWLT forum, https://www.bmwlt.com/forums/rt-series/ ... ueing.html

I would not use Steel Wool on Chrome as it is far to abrasive and we used to make Steel Wool quality Rod. Better with the creams-Autosol etc.

scunny12 wrote: I would not use Steel Wool on Chrome as it is far to abrasive and we used to make Steel Wool quality Rod. Better with the creams-Autosol etc.

I agree, far too abrasive. Camcoat recommended using 0000 grade steel wool to clean any stubborn marks off my Ceramic Coated headers without damaging them? I find using a Magic Eraser Sponge works  perfectly well and brings them up a treat. A Magic Eraser with Autosol might be a good option to try on chrome?.


Ps. Try not to run your bike stationary. It'll accelerate blueing without the forward motion air cooling.


(I'm sure someone will be along to prove me wrong very shortly)

How much does the coating cost?

Beagle wrote: How much does the coating cost?

It cost me £220 (I paid cash) + Vat for them to be coated all the way to the exhaust noise valve. They measure the area before giving a cost? It'd have been roughly £110 + the dreaded if I'd had them just done to weld after the O2 sensors.
I'll try and find a picture. Lc

Cheers

Keep it in a box in the attic after installing an Akrapovic.  ;D

Do Akrapovic offer exhaust headers for a Wethead or is it just a silencer.

Just a thought, has anyone changed their chrome headers for stainless steel.

From experience with a 2007 Hexhead, yes, they still do discolour, more brown than blue but can be aggressively polished back to shiny.