Topic: Cleaning Exhaust Pipes

[SD750F]

I have a factory original and very dirty 4-1 for my 1978 CB750 Super Sport. After finding bad rusting and a damaged muffler I was able to save the pipes only to find excessive carbon build-up inside. I mean the ID is actually restricted due to the build-up! Wow the last owner didn't take care of this bike. I want to hear feedback on the best way to clean out the build-up...

Waiting for some good feedback.

Scott

[736cc]

Ever hear the expression "blowing-out the carbon"? It entails running the #$%* out of the bike

[billstron]

I recently bought an old pipe #1 of a 4to4 set.  The ID was pretty coked up on it too.  Mine looked more like oil residue than carbon, though.  I put it on my bike and ran it.  I haven't had any problems. 

[Bodi]

With the old jawa Californian 2-stroke I had to take the muffler baffles out every couple of months and throw them on a campfire to de-coke them. I fear that would be bad for the chrome on your headers though.
You can get cylinder decarboning spray - GM dealers used to have a good one - but I generally cleaned up my carboned car engines by pouring water into the carb with a hot engine. The thermal shock would scale the carbon off.
So you could heat up the pipes with a torch and drop them in a tub of cold water. The crud might just flake off.