Topic: Surface Rust on Exhaust

[Popwood]

The exhaust pipes on my ‘75 CB750 are not pretty but they work. Some outright holes have been filled with silver solder but there’s quite a bit of surface rust. What can I do preserve pipes and keep the rust from getting worse?

[OldGreyBeast]

You can use acid to neutralize the rust if you don't mind them keeping their patina.  It's been a while since I've done it, it seems like a fairly weak solution of hydrochloric acid will do it.  I followed a guide I found online last time I did that (11 years ago) but the rust hasn't come back on my old pickup since.

[beemerbum]

Regular Coca Cola is often touted as a remover of light surface rust, seriously

[jmd10259]

I use lime away. Takes off rust in about 15 minutes. Best stuff I've used.

[Popwood]

Thanks for your suggestions.  Hoping to learn about something that will get rid of there rust and can then seal the surface so it doesn’t easily return. Not looking for an easy fix, something that would take time, effort and even $$ would be worth it to keep original exhaust on the bike.

[TwoTired]

Have you tried oooo steel wool?

[beemerbum]

I just recalled that I was successful in removing rust from my chrome wheels using chrome polish and a lot of elbow grease

[MauiK3]

Steel wool would damage the chrome and perhaps increase future rust.
Chrome polish should work

[seanbarney41]

Steel wool would damage the chrome and perhaps increase future rust.
Chrome polish should work

it won't hurt much...and that chrome is basically gone already.  0000 steel wool soaked in chrome polish and/or wd40 can really works in an forms a temporary barrier to further rust.

[Don R]

 X2 on the 0000 steel wool. 000 will show visible dulling, it's crazy. I like the turtle wax chrome cleaner too.
 There are those of us that use an oz of 2 stroke oil in the gas to protect the tank and the insides of the mufflers. You rarely see a 2 stroke bike with a rusted out muffler.

[ekpent]

I'm a 4 aut steel wool guy also. I like using it to get the first layer of crud off with dawn or other dish soap and a water. Slippery soap helps on the scratching and some water to wash away the grit.

[Deltarider]

How about tin foil?

[Popwood]

I have no doubt 0000 steel wool, even with a soapy water or oil as lubricant will scratch the chrome. Given the surface condition of the pipes maybe I shouldn’t worry about that. But before doing possible hard I’m going to use Evaporust soaked paper towels laid flat on the rusty surface, then tightly wrap the pipe with plastic to keep the Evaporust from drying. I’ll give it two/three hours to work and see what I get. Will report back.

May also do a section using The Works Shower and Tub cleaner. I’ve had some good results soaking smaller rusty parts in full strength solution. Will try paper towel and plastic and see what I get. 

[grcamna2]

I have no doubt 0000 steel wool, even with a soapy water or oil as lubricant will scratch the chrome. Given the surface condition of the pipes maybe I shouldn’t worry about that. But before doing possible hard I’m going to use Evaporust soaked paper towels laid flat on the rusty surface, then tightly wrap the pipe with plastic to keep the Evaporust from drying. I’ll give it two/three hours to work and see what I get. Will report back.

May also do a section using The Works Shower and Tub cleaner. I’ve had some good results soaking smaller rusty parts in full strength solution. Will try paper towel and plastic and see what I get.

Evaporust like that may do it, & if it's wrapped in Saran wrap/plastic shrink wrap? that will keep the Evaporust from drying.

[ekpent]

Have you ran the bike yet? I had an old kind of rusty 341 pipe once that had a death rattle when it was running probably from some interior baffling broke down. Looking forward to your chemical results, never have tried Evaporust before on anything.

[Don R]

 I've never felt the need to rub 0000 on really nice chrome, but it has worked well for me on rusty chrome. Aluminum foil works well also, in addition the particles seem to fill the pock marks.

[Bankerdanny]

I wouldn't use 0000 on show chrome, but if your pipes are already rising you don't have show chrome and a follow up with simichrome which should deal with the vary fine marks the 0000 leaves behind.

[newday777]

Rust jelly works. Spread it on and cover with saran wrap to keep it from drying out. Let set for 24 hrs then check. Then rise off when finished.

[74CB750K4]

I use steel wool and mother's chrome/aluminum polish on everything. If it was brand new chrome I wouldn't, but it's fine for an almost 50 year old bike I continue to ride.

[grcamna2]

I use steel wool and mother's chrome/aluminum polish on everything. If it was brand new chrome I wouldn't, but it's fine for an almost 50 year old bike I continue to ride.

#0000 extra fine steel wool(it's the 'finest' stuff  made)is very gentle to chrome;I never saw any streaks/scratches after using it even in the bright sunshine.

[Stev-o]

Steel wool would damage the chrome and perhaps increase future rust.
Chrome polish should work

it won't hurt much...and that chrome is basically gone already.  0000 steel wool soaked in chrome polish and/or wd40 can really works in an forms a temporary barrier to further rust.

+1...appears that some of the chrome is gone.  I've always used 000 steel wool with WD-40 with good results.

Keep it out of the rain and it should not get worse.

[God of Thunder]

I used Brasso - and its worked phenomenally. It might be bad - but heck it made some rusted parts look brand new.

[TwoTired]

SOS pads have been used to polish chrome on cars for decades.  I have a revere ware tea kettle that still shines like new after using SOS pads.  It's soap and steel wool.  All my SOHC 4's get #0000 steel wool for cleaning the chrome, including the mufflers.  But, the chrome was thin and not in the best of shape when I got them.  But what chrome remains is bright and shiny.  Pits remain, of course where the chrome is gone.  But, bare metal will shine until it rusts again.

#0000 steel wool is also used for making mirror finishes on many wood working projects to make them shiny and smooth.  It doesn't add scratches.

[Popwood]

Here are side by side photos, before on left, after on right. Definitely improvement. In the after photo, I used Evaporust on the muffler on the left side of the muffler seam, and The Works, tub and tile, on the right side of the seam. Both worked reasonably well but I think Evaporust worked better, but neither perfect. I soaked two paper towels for each side and positioned them on each side of the seam. Wrapper the pipe in plastic sheeting and kept it closed with some tape. Left it in place for four hours. I suspect a second treatment would show additional improvement. (Looks like I can only get after photo attached)

But before I do that, I’ll get some 0000 steel wool (or 3M grey colored abrasive pad, same abrasiveness as the 0000 steel wool).

I’m now wondering what can be done to inhibit further rusting. Anyone every try any brand of high temp silver/aluminum paint on exhaust? Or, if I wanted to spend a few hundred, wonder if powder coat chrome would stand up to exhaust temps.

[Popwood]

Photo in my last post is before. I’ll try posting the after photo here. Sorry for the confusion