"I would expect much crisper shifting with that setup than a wide-range triple up front. "
If you build one of each and offer the comparative ride report, I'll be pleased to read it. I still have the gear chart in front of me the last time Patrick Moore offered the theory that three gears in the back is objectively superior to three gears in the front. That gear chart has a 36T ring with a 14/18/27. I built a three cog freewheel and ran it on a 120mm O.L.D. hub, but not with a derailleur. Usually (and I expect now) Patrick Moore will say how he is philosophically opposed to a tensioner of any kind and prefers long horizontal drop outs and a QR skewer for manual gear choosing. The thing that keeps coming to mind is the classic 5-speed freewheel: 14-17-20-24-28. That has all the span we're talking about. A nice 120mm O.L.D. frame with a 1x5 drivetrain, friction shifted with a modest rear derailleur would do all these things. Don't be surprised a drivetrain of that kind pops out of my workshop in the next 3-6 months as well. I encourage Ted and Patrick to build their ideas also. Bill Lindsay El Cerrito, CA On Sunday, April 28, 2024 at 7:10:32 AM UTC-7 Ted Durant wrote: > On Saturday, April 27, 2024 at 12:41:12 PM UTC-5 Patrick Moore wrote: > > But I keep coming back to theoretical efficiencies: IIRC, the gearing > effect of tooth jumps in back are more or less double what they are in > front. So the question is, how to get just 2 or 3 big jumps in back without > a IGH. > > > Just build a 3-speed cassette and fill the rest of the space with spacers. > > Bill's 46-36-24 is jumps of 25% (46-36) and 41% (36-24). An equivalent 25% > jump in back would be 15-19 (24%), 16-21 (27%), 17-22 (26%), 18-23 (25%). > An equivalent 41% jump in back would be 16-24 (41%), 17-25 (39%), 17-26 > (42%), 18-27 (41%), 19-28 (39%), 19-29 (42%), 20-30 (41%), 21-31 (39%), > 21-32 (42%), ... > > A very close equivalent to the 46-36-24 in front would be 15-19-28 in > back. Pair that with a 44T chainring and you'd have 42-63-79 gear inches on > 700x32C tires. At 22t of required chain wrap, take your pick of any rear > derailer. I would expect much crisper shifting with that setup than a > wide-range triple up front. Combine it with a compatible index shifter and > you'll have a nice 3-speed externally geared hub. > > If you were so inclined. > > Ted Durant > Milwaukee WI USA > -- 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/3e124769-485e-4532-93b5-6f2efb51e0aan%40googlegroups.com.
