My fixed is based around 25 year old (approx) Reynolds 531 framed Carlton I bought off ebay for £80, powder coated, and equipped with whatever gubbins I have lying around in the garage. The other day it's front wheel was fitted with a studded tyre in case of ice, but I decided that was un-necessary so at the last moment before setting off I swopped it out for a Fulcrum 7 which had 700x25 slick on it. Rode 38 km .. mostly flat loop, but with one or two nasty little lumps which were at the limit of what I could get up with a 74" gear on. Time was 1h 23min.... which I was rather pleased with, first time I've averaged over 16 mph on a solo ride. Today, in similar meteorological conditons, dressed in the same clothes, I rode exactly the same loop on my "best bike" - a Van Nic Yukon, with full Campag triple drive train, hand built wheels... I bike I have spent a lot of £££ on. Time 1h 22 min and I had to bust a gut to beat the previous time. The weight of the two bikes is very similar, and it got me thinking whether in fact, if I got my gearing dead right and improved my downhill spinning a bit I would actually be faster on fixed over this sort of short distance. Any one else made any comparisons?