I run a half step plus granny on my Bombadil. It is a 3x7. The 7 is a freewheel, Suntour New Winner, 12-34 if I remember correctly. The crank is a Sugino with TA chainrings for the half step - I think 38-41 with a stainless steel 24 for the granny. With only a 7 speed on the rear, the half step makes gives me more usable gears. I ran a 3x5 half step plus granny on my Paramount P-15 a half of a century ago (currently a 2x6). The longer wheelbase of the Bombadil makes for a better chain line. Rivendells are perfect for half steps because of the long wheelbases and required “cross chaining” for best use of the half step. The narrow freewheels (or cassettes) allow less dish for a stronger rear wheel. With the excess number of cogs on modern cassettes, having a half step is not as necessary of a thing to avoid big spaces between the gears. Way back when, I used to tape a gearing chart to my stem.
Laing Conley Delray Beach FL On Sat, Jul 26, 2025 at 2:05 AM Shannon Menkveld <[email protected]> wrote: > The Shimano 9-speed 12-36 is a half-stepper's dream cluster: > > 12-14-16-18-21-24-28-32-36 > > Makes for a 7-9% half step with any of: > > - 48/45 (107 - 33.4 inches) > - 45/42 (100" - 31.2", probably what I would build. 45t chainrings are > limited to 110 bcd, so far as I can tell.) > - 42/39 (29" - 93.6", best bet for a 130 or 135 road crank.) > > Similar logic applies to 1.5-step and 2.5-step setups. > > The SRAM, but not Shimano, 10-speed 11-36 just adds the 11 to the existing > progression, giving a 112 inch high gear, at the costs of going 10 speed. > Not worth it, IMHO, unless I was standardizing all my bikes on 10. (Which I > wouldn't do, the price jump from 9 to 10 speed parts is still pretty huge.) > > You do have to use a road double front derailleur, or an older triple > that's marked "for half step gearing" or somesuch. I know there's a Deore, > and there are probably others. They don't have the dropped and profiled > inner cage plate, which will hit the middle ring when you're upshifting. I > use a Suntour AR, and it works great. > > I built my HS+G because > > - I was converting a bike that I bought as an un-Drewed single speed > back to geared drive. > - I needed low gears > - I was cash broke and parts middle-class > - I had a NIB 1980 Suntour Superbe rear derailleur that I really > wanted to use, but its max cog and chainwrap are specc'd at 23t. > - All my freewheels were 1x-26 clusters > - I'd always wanted to try a half-step. It appealed to me, primarily > because duplicate gears offend my sense of rightness. > - I was broke > > It works a treat. The ~7% gaps are perfect, especially on the flats and > into the wind. And, yes, with the Rivendell Silver D/T levers, it's a lot > of fun to shift. (The way I do it is, from a stop, ride up on the 42 (~14% > jumps, not a problem when you're accelerating,) until I'm just spinning > just that little bit too fast. Then upshift the front and iBob's yer uncle. > > The Peugeot PKN-10 has 48/34 x 12-14-16-18-21-24-28-32, for a 28.4" - 117" > 2.5-step "alpine" setup. > > The GT Karakoram will get 42/34/22 x 12-14-16-18-21-24-28-32, for a > 92.1"-18.1" 1.5-step + granny. (I may try the double version on the > Peugeot, as I think it will make the big ring even more useful.) > > --Shannon > On Friday, July 25, 2025 at 7:27:50 PM UTC-7 Robert Tilley wrote: > >> Brompton 6 speeds are basically half-step gearing. Three speeds on the >> internal hub with two cogs making 6 gears spaced about 25% apart. I’ve >> never used a true half-step. >> >> Robert Tilley >> San Diego, CA >> >> >> Sent from my iPhone >> >> On Jul 25, 2025, at 7:13 PM, Ted Durant <[email protected]> wrote: >> >> On Friday, July 25, 2025 at 12:57:43 PM UTC-5 Patrick Moore wrote: >> >> Shannon’s post reminded me of the pleasures of half step gearing... >> Does anyone here use a half-stepped system? >> >> >> This is a timely post for me. I recently took delivery of a new Chapman >> "light touring" bike and, as part of the process of deciding what did that >> bike want to be, I worked hard on a half-step gearing setup. It turns out >> to be impossible to buy a cassette that works for that, so I cobbled >> together something from Alibaba and spent some time with it on a test >> bike. I'm pretty sure I'm as nerdy about gearing as anyone, and I have the >> Excel workbook to prove it. I am supportive of the idea of half-step and I >> wanted it to work. In practice, though, I didn't find it worked well for >> the riding I mostly do around here. >> >> My take on it is that, if you are limited to 5 or 6 cogs in back, then >> half-step makes sense for all the usual reasons. Like Shannon, my >> preference is for a 15% step between gears, just enough to be meaningful, >> not so much that I have to ride at a cadence that's outside my comfort zone >> between gears. The Shimano 9-speed 11-32 cassettes are >> 11-12-14-16-18-21-24-28-32, which is average steps of 14% from the 12 to >> the 32, with a minuscule 1.4% standard deviation among those steps. The >> 11-12 jump is pretty much a toss - okay, fine, I can turn it to 11 for that >> little extra more at 50kph. >> >> I also understand the idea of efficiency and not having any duplicate >> gears, but in practice my 2x9 is an 8-speed transmission with a two-speed >> transfer case and one extra gear at the top. I'm normally in the big ring, >> shifting to the small ring when facing a sustained climb of, say, 5% or >> more. In either ring I've got lovely, consistent 12-15% jumps between each >> cog. What I really care about in front is that the change between the big >> and small ring is around 30-35%, big enough to get me to some appreciably >> smaller gears, but not so big that it's a massive change in RPMs when I >> shift. A 42/26 combo is a giant 48% change (I use log-differences...), >> which is way too much for me unless I first shift the rear at least 2 cogs. >> Minimizing shifts is another form of efficiency, and I'm happy to use the 9 >> cogs in back to improve that aspect. I've learned not to grind my gears >> (hah) over duplicate gear combinations. >> >> With 11+ cogs in back it opens up another style of gearing, which I have >> on one of my Sams. The small part of the cassette is 1-tooth jumps, 11-15; >> the large part is 2+ jumps, 11-15%, average 13%, stdev 1.3%. This creates >> something of a 4-range gear setup - 1) big gears/small jumps; 2) medium >> gears/medium jumps; 3) medium gears/small jumps; and 4) low gears/medium >> jumps. Well, that's the theory. In practice I end up using it as simply >> high gears/low gears, and I tend to spend most time in the bigger 2/3 of >> the cassette. >> >> 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 [email protected]. >> To view this discussion visit >> https://groups.google.com/d/msgid/rbw-owners-bunch/6577996b-ec92-4ffa-98a2-1c5748ab947en%40googlegroups.com >> <https://groups.google.com/d/msgid/rbw-owners-bunch/6577996b-ec92-4ffa-98a2-1c5748ab947en%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 [email protected]. > To view this discussion visit > https://groups.google.com/d/msgid/rbw-owners-bunch/8a9eb0da-3595-4b74-86d9-6c3236aca823n%40googlegroups.com > <https://groups.google.com/d/msgid/rbw-owners-bunch/8a9eb0da-3595-4b74-86d9-6c3236aca823n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. 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