only things i use now are things like a good carb/TB cleaner when i take stuff apart to clean it out. much rather do it the manual way so i know whats going on. at the most i might toss a bunch of combustion chamber cleaner into a cylinder if something is wrong.
I agree with what's said here, mostly. The types of driving techniques that this site supports such as EOC isn't what the majority of engines we have on here were designed to deal with. Extreme enough driving like that with no chance to heat up like winter tends to offer can lead to deposits building up in the combustion chambers and the backs of valves that don't in a normal running engine.
Injectors start to have a bad spray pattern because every time the engine is shut off a little bit of fuel stays on the nozzle and the hot engine boils off the remnants but not all of it evaporates. There is always a tiny bit of fuel left behind and the situation is exacerbated by constantly turning off and on a hot engine trying to save fuel economy.
We could further expand this by thinking about what EOC does to the engine internally. Every time you kill the engine you lose oil pressure and oil drips back into the pan, when you go to restart your pistons will run on whatever is stuck to the walls for a little bit until pressure is regained and oil is sprayed from the rod journal up to the piston. Not a big deal for a cylinder at or near TDC but a piston stopped at BDC has to climb up a dry wall. You get that every time you start the engine, yes, but normally that's a few times a day, not once every mile or so.
However, a tank every once in a while for driving it like you stole it will usually take care of the deposits. Unless, of course, you baby the engine all the time anyways, then I wouldn't recommend that as the piston extends further up into the combustion chamber at higher rpm and if a ridge has worn in the cylinder for any reason it gets ugly fast.
I was mostly wondering since I have an '87 Honda VFR 700 motorcycle that most likely needs the carb cleaned to remove varnish. It is my understanding that ethanol additive promotes varnish buildup in engines, the carb being the most susceptible. Of course letting a motorcycle sit for the winter with gas in the carb doesn't help either. I bought it about 4 years ago, not sure about how well it was taken care of ... I haven't been a good owner either, it's been sitting and needs some work to make her roadworthy - that whole "time and money" problem.
I suppose a thorough mechanical cleaning will be in order, but was curious about the claims of the two products mentioned in the thread title.
Ethanol is great for cleaning out engines. Back in the "old days" when only 7-11 sold E-10 in Virginia I remember my dad saying that if you started running a car on 7-11 gas after it got old you'd be in for problems as it would unleash all sorts of gunk into your fuel system at once. If you had run the car on ethanol fuel since it was new there would be no problems, since there would not be the buildup.
I was mostly wondering since I have an '87 Honda VFR 700 motorcycle that most likely needs the carb cleaned to remove varnish. Of course letting a motorcycle sit for the winter with gas in the carb doesn't help either. .
Most motercycles have a drain screw in the bottem of each carb. They should be drained for the winter.