The shit that passes for gasoline these days is LOADED with toluene and xylene - both WONDERFUL solvents ..... of paint, o-rings, plastic, rubber ...... you get the idea. As long as you don't let the bike sit for over six weeks at a time without putting fresh fuel in it, you should be good. After that amount of time the solvents evaporate from the mix of poop and leave asphalt and tar - which is used to "bind" the solvents into the mix ...... only the mixture is azeotropic and the stuff separates and goes away. I have found that simply adding the solvents BACK to the fuel (lacquer thinner) will do nicely when one is left to sit too long ....... that and a good LONG ride to get some fresh fuel in there ....