That is so true That color is actually the chromium depleted oxide layer that is necessary for corrosion protection. The reason for the different colors is because the heat coming right out of the head is more prominent the closer to the head. As the heat dissipates farther down the muffler, the color will change because the heat is less farther down the muffler.

Chuck

Hi Danny,
Sure, a gas torch will cause the metal to oxidize if sufficient temperature is reached. Like we said, that color is a chromium depleted oxide layer. It will stay a chromium depleted oxide layer until it is removed. This being a motorcycle muffler ( I ride them too, well, not your kind but H-D's) and the muffler's are not all that thick, so your muffler is going to stay discolored throughout. The chromium depleted oxides are only on the surface, but the muffler will stay discolored all the way through. The heat from a motorcycle exhaust is not quite as high as the heat from the welding process, and that is what determines the thickness of the oxide layer. Sorry, that's just the nature of the beast. On my M/C the heat tint is only where the pipes bend coming right out of the head so I put heat shields on mine to hide that color. Now, you can't even tell it. :-)

Chuck

Chuck

Yea saw that. The same effect is also applied to stainless steel muffler shells. It's just that that was the only example I could find.

From what I gathered, this titanium "scorched" muffler is not made out of all titanium. Good luck buying a titanium muffler for $329.00, or whatever it is in English pounds. I paid more than that for my stainless steel plated mufflers for my M/C, and titanium is just a little more expensive than SS.

Chuck

Back when I had an ear ring and a pony tail I used to do some titanium sculpting and jewlry making.

While you can heat tint Titanium and create really cool colors, most decorative works these days are done with an electro chemical bath. It's pretty hard to produce consistant color with Ti oxides with heat and atmosphere unless you spend huge amounts on a chamber and the inert gas to fill it. Here is a good link that tells a bit about refractive metal tinting http://pubs.acs.org/cen/80th/niobium.html

The tint on those mufflers on the above link was not produced on the bike.. My guess is that those are just little sheet metal covers wrapped around the real mufflers and the tint was applied in a similar fashion to these creepy nose rings http://nitrous.zoovy.com/product/FRISBY?META=froogle-FRISBY

They draw the metal slowly out of the electrochemical bath while increasing or decreasing voltage in order to produce a consistant variety of colors and transitions.

I did my work with a WP 20 water cooled torch, a 4 inch by 6 inch copper argon purge plate and a really big custom cup that drank about 45 cfh but could hold a 1 inch stickout.