Re: [CR]The idle ramblings of a freewheeler.

(Example: Framebuilders:Tony Beek)

In-Reply-To: <3AC9241B.E7845F20@fridayscomputer.com>
References: <3AC9241B.E7845F20@fridayscomputer.com>
Date: Mon, 2 Apr 2001 22:10:14 -0400
To: Steve Freides <steve@fridayscomputer.com>, Classic Lightweights <Classicrendezvous@bikelist.org>
From: "Sheldon Brown" <CaptBike@sheldonbrown.com>
Subject: Re: [CR]The idle ramblings of a freewheeler.


Steve Freides wrote:
>I would like to know if, during the 6-speed freewheel era, 13-26 was a
>popular choice for a freewheel. Whether it was that or just close to that,
>I'd like to know the specific cogs usually used.
>
>All my asking about chain for my Raleigh has reminded me that I have
>mixed-breed Shimano freewheel on there now because that's how I could piece
>together the combination I wanted, which is 13-15-17-20-23-26. I recall
>hearing that using a 22 in the next to the last position was more common but
>that seems like too big a jump to me. I'm pretty sure the freewheel body
>I'm now using originally was configured as 13-14-16-19-22-26.

I would prefer the latter combination, particularly because I consider the 17-20 jump too large for that part of the range.

My preference has always been to have small jumps in the middle and high range, with biger jumps near the bottom.

In the higher end of the range, to make the upshift without bogging down, you need to be able to get up enough speed in the lower gear to be able to turn over the higher gear. Back in the 5-speed era, 14-17 jumps used to be very common, with 52 tooth big rings. It is very hard to get going fast enough in the 52/17 to be able to spin the 14 comfortably.

Some cyclists used to conclude that the 52/14 gear was too high to be useful to them as a result, when, actually, the problem was the big jump making the 52/14 inaccessible.

In the middle, cruising gear range, close ratios are good because they let you fine tune your gearing in the range where you spend most of your time.

In the lower range, big jumps work well. The mere act of shifting while climbing, especially on older derailer systems, would cause you to loose some speed, due to having to ease up while making the shift. If the jumps were too small, the gain in gearing would be offset by the loss of momentum.

Indeed, the old "alpine" type freewheels with a big jump at the bottom made a lot of sense back then, and they still do in the form of Shimano's "Megarange" units. My O.T.B. came with a 4-speed 14-16-19-26, with a 48-30 crankset. Worked great! The same is true of Shimano's 14-16-18-21-24-34 and 14-16-18-20-22-24-34 Megarange units (though I'd prefer 14-15-17-19-22-26-34.)

(The term "alpine" gearing later became debased into meaninglessness when adopted by marketeers, but it originally referred to a system like this with a low "bail-out" gear.)

Half-step fans (of which I've never been one) would prefer the more even jumps of your 13-15-17-20-23-26.

Sheldon "Pear Shaped" Brown Newtonville, Massachusetts +--------------------------------------------------+ | Take sides! Always take sides! | | You will sometimes be wrong--but the man who | | refuses to take sides must _always_ be wrong. | | Heaven save us from poltroons who fear | | to make a choice. --Robert A. Heinlein | +--------------------------------------------------+

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