Re: Scientific evidence for decarb
What kind of evidence do you want? Nobody is going to tear down an engine, take pictures, reassemble the engine, then decarb it and tear it down again so they can take before and after pictures. That's simply rediculous. Proof of effectiveness comes in two ways: 1) Compression and 2) Runability. Any two stroke that has spent a good amount of its life trolling or perhaps serving pontoon duty where it sees lots of low speed operation can experience carbon build up to the point where it loses compression due to the rings becoming stuck. Doing a compression check on those engines usually shows one or more cylinders down on compression and the owner reports hard starting, rough idle, high fuel consumption, etc. As with any repair work, always do the simplest and least expensive things first. If the electrical system shows good spark and the plugs are ok, do a compression check and follow that up with a thorough decarb. There is pretty fair chance compression will return to near normal. As for runability, getting compression back to normal will help that as well. Especially starting and idle performance. Continued use of a product like SeaFoam, Power Tune, and others will reduce the need for decarbing.
I have a two stroke LawnBoy mower that is still dripping black gunk from a decarb. You got -- poor performance was corrected with an enema of SeaFoam.