Muffler fix | GTAMotorcycle.com

Muffler fix

Merkid

Well-known member
Has anyone figured out a way to remove the road rash off a factory exhaust muffler and buff back out to try to get looking original?
 

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What was the original finish? How deep is the rash? I am assuming aluminum? You could sand out the rash (be careful as it's easy to make it deeper if using power tools) and "polish" the whole pipe. You don't need to go to finer grits to get a mirror finish, just stop once the sanding marks are gone and pipe looks uniform. Not perfectly factory but can probably get close enough. Alternatively sand and then bead/shot blast for a finish. Option the next is bend up a cover plate (cough, heat guard) and rivet it over the wound.
 
Has anyone figured out a way to remove the road rash off a factory exhaust muffler and buff back out to try to get looking original?
My guess is the can is stainless steel. If so, it can be sanded and polished -- just not easily.

You need a 4000-6000rpm grinder and progressive sanding disks at 240, 400, 600, 1200, 2000, 5000 grit.

Starting at 200, you fully grind out the rash, working the bad area until you can no longer see any of the rash. You move to the next grit once the area is uniform, all you should see is the swirly scratches from the sandpaper.

The follow-up sanding is a progressive effort to reduce the surface back to a glossy mirror. Sand till all the swirls and scratches from the prior grit paper are gone. Rince and repeat till you're done at the 5000 grit level.

Note: skipping a grit in the sequence does not save time and effort - it does the opposite!

If the can is aluminum, the job is easier - start at 400, then 1200, then 2000 then use a polishing pad with a little paste or rubbing compound.

If it were my project, I'd take it to a metal finisher, with the right shop tools it's not that big of a job.
 
I think that would polish out with patience , I polish a lot of stainless boat bits. I'd follow mikes series of sanding but I'd stop at 1000g and go to brown and green polishing compound on a high speed wheel . You can buy brown /green polishing compound on bars at princess auto. Use a D/A sander or a random orbit if you have one , or just by hand will get you there , just slowly , which is not a bad idea.
Remember its a pretty thin skin
 
It looks heavily gouged, don’t think there’s enough material to polish it out
 
Not to derail OP's question .....
Is there a way to polish off the heat stains from a SS header?
The blue and yellow stains may have also come from left over and unnoticed preservatives (when the bike was new).
 
Not to derail OP's question .....
Is there a way to polish off the heat stains from a SS header?
The blue and yellow stains may have also come from left over and unnoticed preservatives (when the bike was new).

Yep, common question on ADVRider and other GS forums, the headers on the boxer engine turn blue almost immediately when you ride it off the dealer lot.

There's a product called Blue Away that works well for that:

 
It looks heavily gouged, don’t think there’s enough material to polish it out
You can take stainless cladding to the thickness of tin foil...there's lots on a muffler.

SS is easy to polish, can be done chemically (passivation) or mechanically. Getting scratches out is not easy- they dont polish out, only sanding ( or brushing for matte finish).
 
Yep, common question on ADVRider and other GS forums, the headers on the boxer engine turn blue almost immediately when you ride it off the dealer lot.

There's a product called Blue Away that works well for that:

Most prepackaged SS potions are simply 10% citric acid. This acid passivates stainless by dissolving the free iron that causes dullness and bluing. The cleaned up stainless reoxidizes its own protective surface.

these products won't remove scratches, that takes fine polishing with progressive abrasives.
 
these products won't remove scratches, that takes fine polishing with progressive abrasives.

I didn't get that @Chris-CJ was asking about scratches. Just bluing:

Not to derail OP's question .....
Is there a way to polish off the heat stains from a SS header?
The blue and yellow stains may have also come from left over and unnoticed preservatives (when the bike was new).
 
Cleaning up a very used exhaust is possible.
 
What was the original finish? How deep is the rash? I am assuming aluminum?
Stainless. It's off a 20yr old bike but will try a few options as suggested .

Someone applied a few coats of aluminum paint to a similar one after smoothing down the edges. He said it looked only acceptable...lol
 
I didn't get that @Chris-CJ was asking about scratches. Just bluing:
Correct, so all he needs is a nice chemical bath!

10 minutes in a 10% citric acid tub should do. If he doesn't want to remove the header, a loose wrap using acid soaked rags will do.
 
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Cleaning up a very used exhaust is possible.
I wouldn't use Harpic Bleach on polished stainless, it's a weak hydrochloric acid, great for matte or brushes stainless. HCL might pit and cloud polished stainless.
 
You can take stainless cladding to the thickness of tin foil...there's lots on a muffler.

SS is easy to polish, can be done chemically (passivation) or mechanically. Getting scratches out is not easy- they dont polish out, only sanding ( or brushing for matte finish).
Polishing will make a surface shiny but not fair unless the whole surface is taken down the same amount. The appearance will be dependent on the depth of the scratch.

It's a bit like a butt joint in drywall. The longer the feather the less it is noticed.
 
this is so easy.
go to cdn tire and buy a roll of aluminum sheet that is long enough for your can.

cut to fit canister, put seam at back to hide. pop rivet aluminum sheet right over the old exhaust !

the better you fit aluminum sheet, the better it looks. looks near factory.
 
this is so easy.
go to cdn tire and buy a roll of aluminum sheet that is long enough for your can.

cut to fit canister, put seam at back to hide. pop rivet aluminum sheet right over the old exhaust !

the better you fit aluminum sheet, the better it looks. looks near factory.
Why not stainless. Go with buffing to a high polish or matte.
 

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