Depending on the length of the course, weight is probably less of a factor than people are thinking. Especially on loose ground (Bonneville), it's not uncommon to ADD weight for ballast and traction. Top-speed is relatively unaffected by mass. If you're on a short course, then the weight will hurt your acceleration, and ultimately prevent you from reaching top-speed in the requisite distance. I'm not sure how much of an issue that is with the distance provided here. Buy beyond that, a 6' 200 lbs rider in a tight tuck will be able to go faster than a 5' 100 lbs rider with crap form. Jason Britton went to Bonneville with a rented GSX-R 600. He expected to go 145 no problem. Didn't even get close. Going fast in a straight line is easy. Going REALLY fast in a straight line isn't. It's not that different from track riding in that regard... You can be proficient enough to not be a hazard relatively quickly, but the faster you get, the harder it is to shave time. The faster you get here, the harder it is to add fractions of a mile-per-hour.