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Burning carbon out?

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I recently bought a '99 CR250 and tore it down to have a look and replace the pivot/shock bearings. The bike apparently has a bit of a spooge problem and the entire exhaust is full of carbon. I burned it off of the silencer tube but wondered about damaging the FMF pipe with all the heat of burning the carbon out. Will it damage it or remove the plating? I can polish it again if needed but don't want to destroy the thing. It is soaking in diesel fuel in a parts washer now. Anyone done this or recommend an alternative?

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I recently bought a '99 CR250 and tore it down to have a look and replace the pivot/shock bearings. The bike apparently has a bit of a spooge problem and the entire exhaust is full of carbon. I burned it off of the silencer tube but wondered about damaging the FMF pipe with all the heat of burning the carbon out. Will it damage it or remove the plating? I can polish it again if needed but don't want to destroy the thing. It is soaking in diesel fuel in a parts washer now. Anyone done this or recommend an alternative?

Burn it out, use a parts wash anything will work. Get new packing though.

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New packing is in the mail. Silencers are a peeve of mine. It just seems that the diesel isn't touching the stuff. It is built up pretty badly at the entrance to the pipe, probably close to 3/8"-1/2" thick in spots. I'll leave it in the bath to see if it dissolves any. I've got the time waiting on parts and funds for parts!

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New packing is in the mail. Silencers are a peeve of mine. It just seems that the diesel isn't touching the stuff. It is built up pretty badly at the entrance to the pipe, probably close to 3/8"-1/2" thick in spots. I'll leave it in the bath to see if it dissolves any. I've got the time waiting on parts and funds for parts!

If you live in an area where you do burn piles, put a metal pipe through where the flame will be, and just hang the pipe right in the middle where the flame is. Let it sit there the whole time. Should burn it right out. Did on a little jr50 pipe. Was a suggestion all over the internet.

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Just tried it with limited success with a propane torch and an air nozzle. I could get local hot spots but nothing larger than about 3 in^2. They would glow as I blew the air in and embers would blow out. Maybe I'm just impatient. No burn piles for me in suburban hell.

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Just tried it with limited success with a propane torch and an air nozzle. I could get local hot spots but nothing larger than about 3 in^2. They would glow as I blew the air in and embers would blow out. Maybe I'm just impatient. No burn piles for me in suburban hell.

Got a fire pit? Or anywhere to make a fire outside?

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If you heat the pipe too much the plating will burn off but that will also loosen the carbon.

I heat spots on the pipe cherry red when removing dents with heat and pressure..."plating gone"...but I could care less what the pipe looks like as long as it functions properly.

I just repacked my silencer...make sure all the little holes in the inner screen tube arn't plugged up or it will sound like it still needs to be repacked.

I had to hand clean the screen with a drill bit the same size as the holes, clamped the bit in a pair of vice grips and cleared each hole one by one.

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