I have heard of using lacquer thinner also. I have never tried it because it seems like using the wrong tool for the job. Seafoam, Techron fuel system cleaner, and things like that are specifically made to attach the bad stuff in a carb, while leaving the seals and other parts in tact. Using lacquer thinner might clean the crud out, but it might also wreck other parts.
Seafoam recommends one ounce per gallon of gas. A bike hold between 3 and 4 gallons, typically. This is why I wonder about the "one capful" of lacquer thinner. That's about half an ounce, maybe even less. That's 1/8 the concentration of a regular fuel system cleaner, and I my thinking on that dilution ration is going in two directions: either it's too little to do anything at all, or it has to be that small amount to prevent it from wrecking the engine.
In any case, I buy the stuff made for the job.
Like we say in our engineering department, "When your only tool is a hammer, every problem looks like a nail." Use the right tool for the job, and don't "force something to work" if you can avoid it.
Currently Running Stable:
2010 Honda NT700V
1986 Shadow 700
1986 Honda Trail 110 (Postie Bike)
1987 Honda Rebel 450
1973 Honda Mini Trail 50