Even at 4,000RPM, that Harley Sportster will leave you for dead, until you pull your head out and make a couple downshifts. Meanwhile he's already 5 bike lengths ahead of you and though you will catch and pass him like he's standing still, it will be about 4 blocks down the road, while you are accellerating through 100MPH. Of course on the city streets, that race was ovel long before you actually caught and passed the Sportster. Unless of course, you intend to wind it out for a 1/4 mile and 100+ MPH on city streets. (I'll wager that rarely happens in the real world) -Sean