Advice on decarbing and sludging an 2 stroke exhaust

What's the best way of doing this ?

Sone people suggested pouring some petrol down it and lighting , others say use caustic soda ??

Any ideas and tips ?

A shop teacher from high school once told me to take off my expansion chamber and put it in an old bbq on full blast till it starts to run out the pipe. Normally I just wire wheel the inlet and make sure it bare metal, fillin er full of stove cleaner helps get some of the splooge out from inside as well. I've heard all types of different methods methods though, you just have to find which is the easiest and most effective for you. Hell, I once tried filling my pipe with a bunch of small stones and shaking it around, It doesn't not work, but make sure you get all the stones out :p

Best of luck,

i take a benzomatic torch and point is at the inlet of the pipe. and just kinda hang there for a minute. the pipe makes some interesting noises because its creating the same effect inside the pipe as it does when exhaust gasses are flowing through it, so just know its not the sound of anything going wrong. as heat builds in the chamber it burns off all the carbon and oil deposits in the pipe. when you pull the torch away from the pipe it will smoke a bit, but no fireball is going to come shooting out of the pipe or anything. scrape the carbon near the pipe inlet and outlet with either a screwdriver, or a small steel brush (which i recommend). for safety reasons, wear gloves and safety glasses. ive never had any problems ever with this method, ever, but it doesnt hurt to take extra precautions. this is the method that pacific pipe repair shows on their website, and they have pictures too. i do this out in the driveway away from anything that could catch fire from the torch. 

I take it that burns the smudge out ?

Not my video....


I take mine to the local radiator repair shop and have him throw it in his big cleaning vat for a couple days.  I give him a six-pack and both of us are happy. Pipe is perfectly clean.

I take it that burns the smudge out ?

yes it burns all the crap out of the pipe. fyi, lots of smoke if the pipe is really gummed up. it will look like whats going on in the video posted here, but using a torch burns everything out faster. so more noise, smoke, and flames. dump it upside down when your done like in the video. all kinds of goodies will fall out

Edited by nitrojoe

Torch setup made short work of the pipe for me as well. some high temp paint and she looks and performs like new.

Edited by izcain

Once you get it all clean, then what?  Put it back on and get it all oily again.  I just put some old gas in the pipe with it plugged on both ends, and shake for a few minutes, drain and dump the sludge with used oil for recycle.  

My dad uses acid. It was perfect.

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