Re: [CR]Touring shift patterns, was half-step + granny

(Example: Events:Eroica)

Date: Sat, 10 Feb 2007 16:07:35 -0800 (PST)
From: Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net>
Subject: Re: [CR]Touring shift patterns, was half-step + granny
To: Harvey Sachs <hmsachs@verizon.net>, Classic Rendezvous <classicrendezvous@bikelist.org>, CaptBike@sheldonbrown.com
In-Reply-To: <45CE2B16.1070102@verizon.net>


Well, I've never been a "gearhead" and I think it is completely unnessary to obsess about sequence of ratios or to try to shift through consecutive ratios on a touring bike, especially a triple. Life is too short. I stay on one ring and shift on the FW until it either becomes too hard or too easy, then move to another ring.

But there is one fact I learned here from Peter White a few years ago which I think is worth adding to the current discussion. I was trying to use a 52-38-28 Cyclotourist triple and was having trouble getting the FD to shift from the small to the middle ring. Peter pointed out that this was inevitable because the 52 outer ring forced the FD too far away from the 38T middle to allow it to control the shift from inner to middle properly. He advised holding the difference between outer and middle ring to no more than 10 teeth, and preferably no more than 8. I took his advice and the problem went away. Of course a 10T or even 8T difference may not constitute half-step, but it does limit the advisable spread.

REgards,

Jerry Moos Big Spring, TX

Harvey Sachs <hmsachs@verizon.net> wrote: We've heard a lot of opinions from our esteemed colleagues. Over the past 3.5 decades or so, I've probably toured with most of the possible combinations, and might be allowed to share the opinions I've formed:

1) Riders vary in tolerance for gear step width. What the person who wants to stay very close to some "ideal" resonant (or otherwise) cadence chooses might not be my choice.

2) Terrain varies (duh!) Along the eastern shore, where it's dead flat but the wind varies, I like very close gears and the ability to change them easily; this is less important to me in an area like PA hills, where it's all either up or down, and I'm happy with wider spacing.

3) Systems vary. For me, the breakpoint for even considering 1/2-step is the barely on-topic 7-speed FW. For it, the half-step is pretty close ratio. Beyond 7 (my Weigle), I'm just as happy with thinking about the three front cogs as overlapping "fans" of gear options. Below 7, several of our bikes have half-step, and it works well.

4) 5-speed FW Examples: Susan's early 70s road bike is usually set up with 13 - 31 Regina, and a 40-45 front combo. Nicely spaced, range about 33 - 93, which is better than some "granny" set-ups. My Hetchins, same vintage, uses a 14-28 with 4 tooth front difference, plus Granny, and it is just great for some club rides with longer steep climbs (like Dan Artley's world just above Baltimore. I did RAGBRAI with a (heresy) Cinelli with 4 tooth front change and a 14-28, and it was great in that rolling terrain: sometimes a full step worked, sometimes the half-step allowed "tuning."

5) very early on, I used a sort of traditional French set-up for New England touring: very narrow cog set, and a 28 - 48 front split (double). The problem was that the chainring jump was in a range where I did a lot of my riding, and it was not the easiest shift. One of those cases where an inbetween chainring would have helped... but I didn't get back to that until I bought the Weigle a few years ago.

So, ladies and gentlemen, for me "situational selection," setting up the bikes for what and where, has worked well for vintage bikes. I can't be absolutist for touring. So, I sign off by getting out the fixed gear for a cold windy ride. Or not. :-)

harvey sachs
mcLean VA