I use a theory similar to Jerry's, but I find that even a 10 tooth jump can make smooth shifting with vintage triples a problem. The issue is usually shifting out of the granny onto the middle ring. Often the chain won't land, needing to jump all the way to the big ring first. This makes for rough riding, and messes up your rythym. On classic triple cranks (TA Cyclotouriste, Stonglight 99, Sugino Mighty Tour, 1st gen Deore) or any crankset lacking chainrings with modern shifting ramps and pins, I often prefer a half step style chainring set up, although I don't bother to arrange the freewheel for no duplicate ratios. My favorite set is a 7 speed 13-26 or 28 freewheel, with a 50x45x28 set of chainrings. With only 5 teeth between the big rings, the shift out of the granny to the middle ring works quite well. Just like Jerry, most of my riding is in the middle ring (gear spread of 93 inches to 45 inches or so) with nice evenly spaced ratios. If the wind is from the rear or I'm on a long down hill, get in the big ring. Nasty hill? The granny with a 27 inch low gear is there to bail me out. Of course I'm only using about 11-13 gears out of a possible 21, but I have a simple shift sequence and the front shifts work quite well (or as well as vintage equipment can). If you try to have ten teeth or more between the big chainrings, be prepared for lots of grinding and hesitation as you shift out of the granny.
Tom Adams, Shrewsbury NJ
Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net> wrote: 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 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 _______________________________________________
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