Perhaps if the bit was actually a $500 1/10 scale nitro RC then I'd invest the time in cleaning it after each race, but its actually just a toy that some of us have decided can be modded into an illusion of a real RC. Its fun as hell to play with, and basically no maintenance. If you gain 1/10 of a second in the 10 foot run, its negligable, because your mass-manufactured gears and motors aren't precise enough to take full advantage of each other. You might buy 2 of the same motors and one will run 30,000 rpms and the other may run 27,500. I'm noticing that all of my posts are uber-long, so I'll end here.

Bottom line is, bits aren't precise enough that you'd have an advantage over someone else who hadn't greased their car up before you run them.