[GreenMachine]

Heard it said alot and was wondering if anyone has done it and was it really necessary...Is it something u notice at a certain mileage?  Do the fuels today make it pretty much a rarity?  has anyone torn down a engine with over 10 k and notice serious carbon built up?  Is it more a iron thing vice UCE?  Solicit some thoughts.

[REpozer]

I've got the Lean Burn engine .....same requirement , 10,000 mile De-Carbon.

I'm not going to do it, unless I'm in there for another reason. If it runs good ....ride it.

[Darkside]

Just a thought and I think this is one for brother ace will ths be a necessary evil on the fireball?

[baird4444]

  Use a glug of Sea Foam every tank or so and it won't be a problem.
                 - Mike

[Ice]

I concur.

 Looking at the piston top through the spark plug hole before and after the use of seafoam
was an eye opener. Now the piston crown is just black instead of black fluffy crusty build up.

[RGT]

Just a thought and I think this is one for brother ace will ths be a necessary evil on the fireball?

The fact that the Fireball has shown to run more efficiently(smaller jets and better mileage) would lend me to believe that this would be less of an issue. how one rides and what fuel they use as well as how much oil is being burned will also be factors...

[ace.cafe]

We have low carbon build-up with the Fireball.

The worst offender is poor combustion efficiency, and a slow-moving exhaust tract, which are both present quite plainly in the normal Bullet.
Plus, people run Bullets rich, to try to combat excessive heat, and it leads to carbon all over the inside.
And low speed riding on small throttle-openings doesn't ever blow anything out, either.

Some Sea Foam or something like that can help with these things.

The Fireball probably won't need any decarbonizing until it's ready to have a valve job anyway.

[singhg5]

The worst offender is poor combustion efficiency, and a slow-moving exhaust tract, which are both present quite plainly in the normal Bullet.

@ACE:

Talking about slow-moving exhaust - would you then recommend a free flowing after market exhaust for UCE bikes to replace their bazooka/catalytic converter restricted original exhaust pipe ?  Though I heard this type of modification causes some backfiring, which may be due to incomplete combustion.

Secondly, would the heat range of spark plugs for UCE bikes affect proper and complete combustion ?  

[neil]

regarding decarbonization, I didn't think I'd need to take the head off my 2004 Bullet 65 until I ran out of compression. Bike wouldn't start so I pulled the tank and took off the head. I had a build-up of carbon on the top of the piston and the valves needed to be ground. It was a chore for the first time attempted. After the bike was buttoned up, I felt more assured and would do it again if it is needed. The lack of compression was very noticeable at about 10,000 miles. The bike is going on 14,000 miles at this time and I have removed the electric start stuff so I can tell how much compression the engine has when I'm kickstarting it. Right now I can stand on the kick starter on compression and it won't go down. I'm not a moose so I can only start it by using a manual decompressor I've added to the engine.  Decarbonizing and valve grinding is a dirty job but it's within the ability of most bullet owners if they don't mind getting their hands dirty.

Neil and Buzzy the Bullet.

[mbevo1]

  Use a glug of Sea Foam every tank or so and it won't be a problem.
                 - Mike

I give mine a "glug" every couple of tanks... had it apart at 10K and had virtually no carbon buildup... just used more seafoam and a scotchbrite to clean up the head...

Mike and S&S in Michigan

[ace.cafe]

@ACE:

Talking about slow-moving exhaust - would you then recommend a free flowing after market exhaust for UCE bikes to replace their bazooka/catalytic converter restricted original exhaust pipe ?  Though I heard this type of modification causes some backfiring, which may be due to incomplete combustion.

Secondly, would the heat range of spark plugs for UCE bikes affect proper and complete combustion ?  

Hi Singh,

The free flowing exhaust system of a type which doesn't slow exhaust velocity much, would be a good thing. This means it isn't larger diameter, but would have little restriction.
The issues with backfiring could occur if the changed exhaust system caused the need to alter the fuel injection system to accommodate the changed conditions in the engine. In carburetors, we just change the jets. In FI engines, it's a bit more complicated.

Regarding the spark plug heat range, it's normally correct to use the heat range that is specified in the owners manual. There would have to be some pretty significant modifications to require some change in heat range of the plug.

[bymilesthebest]

2 oz. of Marvel Mystery Oil per 5 gal. of 87 gas keeps mine clean at almost 21000 miles. I use a 5 gal. Old Ironsides can to mx it.

[Rosetap]

Step 1: Get tank to reserve point.

Step 2: Put whole bottle of Seafoam/MMO/Etc into tank.  They're just a mix of well-burning hydrocarbons.

Step 3: Perform an Italian Tune-Up (ITU).  The bike may smoke a bit during the ITU, but this is a sign that it is working.  If there is heavy carbon buildup, smoke will start off blackish.  When smoke changes to whiteish the ITU can end and you can fill the tank up with some fresh gas.

[bymilesthebest]

But Marvel Mystery Oil will keep the combustion chamber clean with  NO build-up of carbon.   Also will lubricate the piston above the rings and intake valve seat and stem. Italians didn't invent MM Oil or deodorant.

[1Blackwolf1]

  And if you are really wanting to you can do a water mist decarbonizing.  Get the engine warmed up good and remove the air filter, using a spray bottle (with engine running) mist water into the intake end of the carb.  You'll have to juice the throttle to keep it running.  You'll know when to stop the misting, exhaust will burn black and then turn to steam when you get it cleaned out fairly decent.