Cleaning expansion chamber

Whats the best way to clean out the inside of my FMF expansion chamber? Any suggestions or experiances are great... thanksss

I have used a braided steel wire with one end in a drill chuck. USE PROPER VENTILATION!!!

Heating the inside of the entrance of the pipe with a propane torch loosened up the main crud area well. A bristle brush knocked most of it off after the heat. Keep an eye on it so it doesn't blue to bad.

I am wanting to try capped ends and a bunch of rocks in the future.

I scraped the hard deposits, sprayed oven cleaner and let it sit for a couple of hours. Then I took a couple of handfuls of sharp edged 1/2 inch landscaping rocks from my front yard, filled the pipe about 1/4 full with water and a crap load of dishwashing soap and shook off and on for about a 1/2 hour. Turned out pretty good!

P.S. Make sure you get all the rocks out after you're done!

purple power all purpose degreaser(wally world has it) duct tape ends shut shake like a margareta rinse repeat, let soak overnight final rinse, like brandy new, change packing also, do mine once a year.

GREAT! I love the ideas guys thanks alot, Im gona try a bunch of these.

I cleaned the inside of my 1994 KDX200 pipe once. The most build-up of hard carbon was right at the entrance (cylinder to pipe connection). The oven cleaner will do well with that also. USE PROPER VENTILATION!!

Have done this many times... BBQ that bugger,really! Bury it in bricks and when they get white hot blow compressed air in it and watch the hot embers fly out.


You cant be serious.

I am waiting for the "after" pics of some shiny, $225 Pro Circuit or FMF pipe, post-BBQ. :lol:

For years, I've taken my pipes to any local engine shop or radiator shop that has a hot-tank. They usualy charge me about $20 or so to tank the pipe, and it comes out looking like a new pipe, inside and out.

Have done this many times... BBQ that bugger,really! Bury it in bricks and when they get white hot blow compressed air in it and watch the hot embers fly out.


thats quite a ritual, almost tribal:jawdrop:

That is really good info to hot tank the pipe. I will keep that in mind.

What exactly is a "hot tank." Do they just soak it in a tank of hot solvent?

It's a tank of hot acid.

What exactly is a "hot tank." Do they just soak it in a tank of hot solvent?
its a tank full off hot caustic will make aluminum pistons disapear quick:eek:

What chemicals are in the hot tank??

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