mylaps has a nice lap time comparison tool. You can use it to
compare lap times for the 250SB race between Eric Bostrom on the Brammo Empulse TTX (half-fairing) and Kenyon Kluge on the 2014 Zero prototype (sport fairing).
From Brian's
race report:
Eric jumped the start, stopped the bike to avoid taking any advantage and being protested, missed the actual start flag dropping, wheelied, then got going again. Not-exactly-what-we-had-planned…. Oh well. Being the cool, calm, and collected racer he is, EBoz put it out of his head and got to work. He was able to make up a lot of ground on the faster backside of the track and even made a couple of passes on the front straight on Mark McKinney (super-fast 250 rider), but would lose the position back diving into Turn 1. By lap 2, he had made it up into a highly contested 3rd place, which he held until lap 4 when the motor controller began reducing current due to temperature. With his wings clipped, Eric fell back into the clutches of Mark McKinney and Robert Wetterau and managed to hold 5th for the final 2 laps. It looked like he might take 4th back at the line, but Wetterau got a better drive off Turn 14 onto the front straight and Eric wasn’t able to push past before the start/finish.
Looking at the fastest times, Eric was about 3.5 seconds faster. That's a pretty significant gap.
Both bikes also lost performance as the race wore on. In Eric's case, the motor controller began to overheat and reduce power by lap 4, following his 2:07.7 fastest time on lap 3. Eric slipped 1.4 seconds on lap 4, 3.0 seconds on lap 5, and 1.5 seconds on lap 6.
Kenyon was riding a 2014 prototype bike. I assume he was using a prototype SR motor with the higher temp motor magnets, which should permit the motor to reach higher temperatures safely. He also had ducting forcing additional air through the motor.
Despite these tweaks, Kenyon also suffered from reduced laptimes as the race wore on. His fastest time was on lap 2 at 2:11.2. He slipped 1.6 seconds on lap 3, 2.2 seconds by lap 4, 2.2 seconds on lap 5, and 2.9 seconds on lap 6.
It's hard to say how much time was lost due to lap traffic, normal variation from lap to lap, and how much to reduced performance. Eric dropped from #3 on lap 4 to #5 for laps 5 and 6, and Kenyon dropped from #8 on lap 3 to #12 for laps 4, 5, and 6.
