You are reading a single comment by @gbj_tester and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
@gbj_tester
I'd be inclined to agree with you, but Leader have built it wrong just as much as the owner has set it up wrong. Since all the 'aero' features on a Leader are pure styling which has never been near either CFD or a wind tunnel, they might as well have gone with a fashionably tight clearance.
The 10-12mm gap which has become fashionable of late is, in many cases, just as much a case of blindly following fashion as the tight clearance was in its day. LOOK did the work and found that on their frame with their choice of rear wheel, the balance of factors favoured a gap. This gives no really useful guide about what the optimal gap would be for other combinations of frame and rear wheel. At least one of the latest generation of TT frames has now acquired a channel in the rear wheel cut out, allowing a close clearance where the edge of the frame meets the tyre sidewall and a large gap in the centre where the tread can freely pull the boundary layer round without a lot of shear drag.