Low end gearing increments on half-step configuration
 

Are narrow even gaps (7%) at the low end range typically provided only by the half-step gearing actually worth it? I guess tuning in some comfortable climbing cadence can be worth it even for short periods of time since it has been said that climbing speed is the first thing to look at if one wants to increase average speed. Sheldon was accenting the importance of small steps at the top end due to need of overcoming exponentially increasing air resistance.
Wasn't able to find any discussion regarding to this sort of thing so had no other choice but to start a new thread.

For the terrain in my area I like the bottom 2 or 3 gears to get easier in a hurry, so I like larger gaps(percentage wise) on the bottom end.

Fred Delong popularized the "half-step plus granny" configuration. Select the outer two chainrings and freewheel sprockets to provide even, half-step gearing, and mount the smallest ring your crank will allow as the inner ring for your "granny" gears.

At the lower end of the range I want much bigger steps then at the high end. At least 20%. The Shimano Megarange 7 speed used on many entry level bikes has a 42% jump from 24 to 34T. When I got the bike I thought it was absurd. After trying it on some local hills with gradient changes not far apart I find it surprisingly useful.

That said if I where touring many km's up steep hills with a consistent grade I might want them closer together, In the 10 - 15% range. By far the high end is where closer intervals between gears is important to fight wind resistance since it increases so much more with the higher speeds associated with tall gearing.

I've got a half-step-plus-granny that uses 26-46-49 chainrings.
The step between the 46 and 49 tooth rings provides about a 6.5% change in the gear ratio.
The 7 speed 13-30 cassette provides steps of about13%, IIRC.
The granny ring, i.e. the 26T ring, therefore provides gear steps of 13%.
Your question was: I gotta admit.. I'm not sure what you info you were seeking. The small, even steps in gear size exist all through the gears that involve the two half-stepping chainrings. Maybe I don't know what "low end range" means?

Half-stepping with my gearing is useful and reasonable and wasn't too much out of date when I built the bike in the year 2000.
With modern 10 or 11 speed stuff (is there 12 speed stuff yet?), there's much less reason to use half-step, and most modern derailleurs aren't particularly compatible with it.

Steve in Peoria

Every bike I own is either half-step, 1.5-step, or 1.5-step-plus-granny. In the mid 1970s I built my wife a 1.5-step 10-speed setup with a "megarange" type bailout large cog. I had bought a used TA Professional 3-bolt crank with 52-42 rings, and I adapted the very common 52-42 / 14-16-18-21-24 1.5-step to 52-42 / 16-18-21-24-32 to help her climb the local hills of Westwood, Beverly Hills, Hollywood, etc. Half-step and 1.5-step are far from obsolete in my book, and either works quite well, even with at least 8 or 9 cogs in back.

John E, half step is pretty easy to understand, but I've never understood 1.5 step.
Can you explain how you use it?
Thanks.

1.5-step works essentially the same way that half-step does, except that the front ratio jump is 1.5 times the rear ratio jump, instead of .5 times. When you want a tight shift, it's achieved by combining a front shift with 1 or 2 rear shifts, rather than the 0 or 1 rear shifts in half-step.

https://i.imgur.com/RuUv9Mn.png

The biggest difference, (other than range, of course,) and why I'm going with 1/2-step + granny (45/42/30) as opposed to a 1.5-step double (46/34 or 45/33), is in the shift pattern.

Assuming you want the next gear in sequence, with a 1/2-step half of the the time you will need to do a double shift. (Up or down 1 in the front and down or up 1 in the back.) The other half of the time, you just shift the front.

With a 1.5-step, half of the time the shift is a double. (Up or down 1 in the front and down or up 1 in the back.) The other half of the time, the shift is a double-double... Up or down 1 in the front and down or up 2 in the back.

This is somewhat harder to remember, and significantly harder to do, especially when you're tired... Which is precisely when you're most likely to really want the exact right gear. (Think of that long, straight, flat stretch of road that leads to your neighborhood. The one you ride at the end of every ride, so you're always tired. And there's always a headwind.)

Really, for wide-range gearing using available parts, a triple with the right chainrings beats the tar out of a wide double on every metric except cosmetics. ("Cosmetics" should not be read as dismissive. Some bikes just look wrong with a triple, and looks are important as long as acceptable function is maintained.)

What really killed the road triple for the recreational roadie was that when compact doubles became popular in the mid-Naughties, the standard road triple was a 53/39/30 x 12-25. Compared to that gearing, a 50/36 or 48/34 makes a lot of sense.The 53 is way too big for anyone who doesn't get paid to ride, so most people rode theirs as a really awkward 39/30, with a 53 that they only used on long downhills. 50/40/30, or better yet 48/38/28 would have made a ton of sense and requires nothing but chainrings. The 50/40/30 doesn't even require a new front derailleur, even given Shimano's shift-testing standards. The 48/38/28 might, although it's one of those "outside the spec but always works great" combos.

But no... they had to keep that dumb 53/39 combo, and so the road triple died the death.

--Shannon

1.5 step has always just seemed clumsy to me. I don't want to have to think that hard about my shifting sequence.
Other than a pure sequential(1x), my preference is for crossover. I understand that it was not really an option back in the day. I use half step + granny for those bikes.

https://cimg9.ibsrv.net/gimg/bikefor...73e43148af.jpg

Does anyone besides me with half-step gearing ignore the large chainring in most riding, until the top two ratios are needed; and otherwise only use the half step ratios when fine tuning cadence on a long (>1/2 mile) consistent route segment (or occasionally to half-step up and down over gently undulating hills)?

Me, too, Alf. I use my gearing almost exactly as you describe. The double shift is a PITA, but it is nice to have sometimes. The vast majority of my rides, though, just don't need that 7% difference. In fact, the vast majority of my rides don't need any shifting at all here in flatland.

Don't you find that the times when you're mostly likely to want that 7% difference are down there in flatland? Especially into the wind?

(All rides in flatland are into the wind.)

--Shannon

I recently did some 1.5 step flatland gearing on my Trek with just a 5 speed 14-32 freewheel and a 34-47 front. 10-12% increments over a narrower range of 29-91 gear inches. Double shifts all the time, hence less gratuitous shifting. A 30 mile ride might even require using every gear. First ride seemed good, so will see how I like it. No duplicate gears and I know when I am in the right gear.

I do like the use of the phrase "gratuitous shifting". :)
When I'm riding one of my bikes with six speed 13-24 freewheels, alongside friends with modern 11 (or more?) speed modern stuff, I'm intrigued by how often they shift and how rarely I do (over relatively flat terrain). Not saying that one is better than the other, but it is interesting to note the differences.

As far as the double shifts.. when I ran a 1.5 step six speed, I thought it was fine. The double shifts did happen, but I could usually shift both derailleurs with one hand at roughly the same time. That was the only bike I had at the time, so perhaps I just got plenty of practice and acclimation?

Steve in Peoria

With DT shift levers and 7 speed 14-28 freewheel, shifting is a lot less convenient than with, say, brifters and a 10 speed cassette. I usually find it easier to adjust my cadence than to shift for a 7% improvement. I generally ride alone, though, and I don't race.

Also, I just hit 77, and I don't have the confidence in my abilities that I did 30 years ago. I can't bring myself to take a drink while pedaling, for example. I can see that brifters might be a real upgrade for me, but those Microshift-Micronew-Sensah brifters are so ugly they offend me, and they're expensive.

Indexed 8-speed bar-end shifters index just fine on 7-speed Shimano-spaced cassettes and freewheels, they just have an extra click. And they're easy to find and not expensive. Shimano did make some 7-speed SIS bar-end shifters. I've seen a SportLX set recently, and there may have been others. Most of them will have a friction option as well, which is a nice thing for a shifter to have.

100% concur that modern brifters are stylistic abortions. The best-looking ones were the 9-speed Shimanos and older Campys. Since the advent of hydraulics, levers are uglier than homemade soap.

(The 8-speed shifter on a 7-speed cluster trick works for STIs, as well, so long as they're not the 8-speed Dura-Ace ones, which only work with 6/7/8-speed D/A derailleurs.)

--Shannon