I've been having fun on my weeknight rides, doing the same 25.5 mile course on each of 7 different bikes. The weather every evening has been much the same - mid 60s when I start with the usual afternoon winds out of the West. Roughly 5 minutes difference between the slowest and fastest bikes. Repeated trials tend to produce the same result. Wednesday and Friday I rode the same bike back-to-back, with the only difference being the wheels/tires. Same gears. Since the bike is a 40 year old Lotus, the wheels are 36 spoke, but one set has MA40s and Michelin Dynamic Classic tires, while the other has Monthlery Pros and Continental Giro tubulars. The first set is considerably heavier. The tires were pumped up to the same pressures. Time difference over the 25.5 miles was 24 seconds, with the heavier wheelset being the faster.
Oh, and red bikes are the slowest and the second fastest.
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