[CR]Streamlining


Example: Racing:Roger de Vlaeminck
From: <StuartMX4@aol.com>
Date: Thu, 19 Jun 2003 04:54:53 EDT
To: classicrendezvous@bikelist.org
Subject: [CR]Streamlining

Re 'fenders' and streamlining IFrom Manfred Curry's Aerodynamics of sails:

"It is an error to suppose that the resistance of the air plays a consederable role only at high speeds. It is true that the resistance increases as the square of the velocity, but it becomes a most important factor at a speed of only six or eight miles an hour. This has been confirmed by the author... by experiments with the Landskiff, a machine for 'rowing on land'.... (which) attains a speed of 30mph ... enveloped in a streamline cover and.... only 18 (when uncovered)."

Photographs of the Landskiff at Avus show the wheels uncovered. Anyone who has had to put close fitting cycle wings on a vintage car will understand how awkward it is and anyone who has ridden a motorcycle with one of those extravagantly large mid fifties mudguards on the front in a cross wind will appreciate that you need a wind tunnel and a large budget to get it right. A normal bicycle mudguard (fender, if you must) falls on the right side of the utility/bloody-nuisance-to-fit equation if you want to keep off some rain. If you were really fussed about streamlining, then you would be riding a recumbent anyway. I would have thought, in any case, that windage losses with a close fitting mudguard might exceed the gains.

Classic content? Well, I think a human powered four wheeled cycle built seventy five years ago fits that bill.

Stuart Tallack in Sussex-by-the-sea