Removing Carbon Deposits

[timberwolfmadcat]

Yes, i dunno how often it needs to be done on the Ruckus, b/c it is a four stroke, but I imagine every 10 - 12,000 km's, the carbon builds up inside the exhaust, making it restrictive, hurting performance. These 2 strokes are way more maintenance than a 4 stroke. Anyways, all you have to do is take the exhaust off, heat it with a propane torch while holding the open side down, and these little black crumbles should fall out. My Vino has about 6,000 km's on it now, and it needed to be done, big time dead spots just got worse and worse. Now 0-60km/h in 200m! If only my rucki had that kind of power... but its not ugly so ill keep the ruck

[Dandy Dan]

Yeah I'd rather be slow and sexy than fast and ugly. I've got 27,500kms on my Ruckus and there is a moderate amount of carbon floating around but I haven't bothered to try and remove it....maybe someday I'll get around to it.

[chanito]

Well tuned four cycles do not need to decarb

[Dandy Dan]

I wish I could say my Ruckus is always well tuned

[wonderslicer]

Similarily, if anyone's interested in a great valve and head carbon cleaner, ask at canadian tire. It's a motomaster brand (CT's store brand), comes in a metallic and red aluminum bottle, and is the only one in the store that I found doesnt mention fuel injectors. There is a real pep and noise difference after about 50km.
Remeber that the bottle is for up to 70l engines, so it's only necessary to use about 30 ml (plus a titch or so)

[Dandy Dan]

How much?

[chanito]

"Normally" a four cycle engine will run slightly lean at high speed (our 8k limit) allowing the slight increase in combustion chamber temp to loosen the carbon in it and the high flow velocity of the exhaust will send any carbon into the big muffler where it will live and be consume in all those heat cycles, but a two cycle is another story because they use a valve in the exhaust side of the engine to alter the shape and size of the port in order to have the engine work more efficient over a wider range of rpms, sadly the place it is located means the valve will be gummed with carbon and will need to be service and clean in order for the engine to keep working OK, also since the 2 cycle burnt oil and gas it Will produce a gummy carbon deposit that will stick to anything it can, we 4 cyclers do not have that problem as the carbon deposit is a dry very fine dark powder (unless your engine burns oil) that will be blow thru the exhaust, hope i did not loose you, so in theory you should not need to decarbonize, unless you do mostly very short low speed runs, then get the other half and go for a long run in the scooter and blow that carbon out of the exhaust

[wonderslicer]

dandydan said:

How much?

Six bucks or so DD...

Chanito, rebuild was less than 600k ago and I cleaned the head thoroughly then, so I couldn't think of how there would be enough buildup to be making the noise. However, it seemed related to the valves (it was a tapping) so I tried the cleaner and it did the trick.
There are so many component parts to the valve system that there are a lot of places where particulate buildup could have an effect. If there is no danger to be done, people might want to try the fluid or an equivalent

Also I had a Honda tech tell me the only time he's heard of deposits conributing to noise is when they were over 6mm(!) thick, which seems impossible to achieve.

So I figured I wouldn't ask them anything again.

[chanito]

:-/Carbon deposit on the spark plug electrodes, can create pre ignition, and that sounds like pinging or a metallic rattle, also carbon deposits large enough to increase compression will create noise
Both can be cure by running the scooter until is warm, and them go for a long hard ride or buy a chemical that will make the carbon burn in the combustion chamber

[wonderslicer]

One more thing for the daily drivers to keep their eyes on, oi!