You bring up a good point Ted about so-called redundant gears, which is something many cyclists try to eliminate as much as possible to their own practical detriment. It's better to approach planning a drivetrain by identifying how low you want your low gear to be, how high you want your high gear to be, and then finding the most user-friendly combination to get there. A big issue with wide-range doubles is that you'll find that you need to drop into the small ring for every hill, whereas if you have a triple, you can generally stay in the middle ring most of the time and save a lot of front shifts, even though you have more rings up there.
For me, I find I don't need anything above about 95 gear inches - above that and I'm going to coast, maybe tuck in and get aero. Maybe 100 tops. On the low end, if it's used off-road or to carry loads I'll want something in the 18-20 gear inch range, but if it's a roadish bike, 24-25 inches is good. So what I tend to do is run a double but size the rings such that I truncate the big gears I'll almost never use, so that I can run a big ring on the double that I can stay in on gentle climbs. 40/28 to 11-34 is a great combo, for instance. Even 38/26 to 11-28 to get some smaller steps on the back, and 38-11 is a big enough top gear for most situations On Sun, Nov 26, 2023 at 1:45 PM Ted Durant <teddur...@gmail.com> wrote: > On Sunday, November 26, 2023 at 12:34:51 PM UTC-6 Jason Fuller wrote: > > I would echo that triples are pretty nice - not only do you get more > range, but the 10-tooth jumps in the front are a lot less 'disruptive' if > you know what I mean. I find the smaller chainring jump means that when I > hit the base of a hill I can often just drop a chainring and leave the rear > alone, and it is a natural gear reduction .. whereas on the wide-low > double, you would be spinning like crazy if you tried the same thing > > > Excellent point, and one that launches me into bike nerd mode... apologies > in advance if this is too much. > > The "standard" chainring gap became 16 teeth when "compact double" 50x34 > combos became all the rage. That's a 39% jump, the way I measure it > (Ln(50/34)), or about 2.5 times the 15.4% jump from 18 to 21 in back. Now, > if you keep that 16 tooth gap but go down to 40x24, that's a ginormous 51% > jump, which is 3.3x the 18-21 jump. I have a 42x26 on my Waterford ST-22, > and it's definitely jarring to drop to the small ring when you hit a hill, > requiring a bit of advance planning to shift a cog harder in the rear, > first. I spent plenty of time riding half-step gearing, so I'm facile with > double-shifting, but after a couple hundred kms I'm too tired for that. For > my Breadwinner G-Road I went with 44x32, which is a gentle 32% jump. It > means there's more overlap in the gearing, or to put it another way, I'm > not maximizing the total range of the system, but I very much prefer to > make that trade-off. At 41%, the 14-tooth gap on the Silver 42x28's on my > Sams is pretty much the outer limit for me. The Wide-Low (38x24) is a 46% > jump which is pretty high. > > Ted Durant > Milwaukee, WI USA > > > -- > You received this message because you are subscribed to a topic in the > Google Groups "RBW Owners Bunch" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/rbw-owners-bunch/yo4eRz3flb0/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > rbw-owners-bunch+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/rbw-owners-bunch/1a3954ba-86af-4775-8090-f3e4bba4fa44n%40googlegroups.com > <https://groups.google.com/d/msgid/rbw-owners-bunch/1a3954ba-86af-4775-8090-f3e4bba4fa44n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/CAGBpHnepek5TG5h-DMc8X%3De0mGFeEzv0CSon6GMzO7oz%3DjoPzg%40mail.gmail.com.
