Top speeds are all good fun, but how often can you actually get there to make the tall gearing worthwhile?

My 28 went over 150mph but (as Andy points out) that was on funny fuel, ram air and many many hours in the workshop and on the dyno. It actually hit 243kmh which is 151mph. I didn't really care at the time because it was in a race and if I could have had another 1mph I wanted it. I was up against 3XV'x that were also pulling very close to the 150mph mark, but my NSR was the fastest BUT.....usual story.....last lap, last corner, I was leading and a backmarker swung across the track in the strangest cornering manouver ever seen and hit me, sending me head first over the tyre wall

For the NSR's I use on the street I'll usually gear them for about 125mph as this is plenty fast enough and gives great scope for power wheelies, which is what it's all about really. My latest 300 creation is geared for 133mph @ 12500rpm just for starters, so we'll see how it goes.