Built My First Half Step... Initial Thoughts
08-16-21 | 06:45 PM
#1
Thread Starter
Senior Member
Joined: Jul 2020
Posts: 1,820
Likes: 1,485
From: Oakland, CA
Built My First Half Step... Initial Thoughts
I've wanted to try a half-step + granny setup since I first read about them in the 80s. I'd never really had the right bike to try it on, though, so it has always been just a "maybe someday" kinda thing. Well, I finally had a bike that needed a thorough re-gearing, and so I went ahead and built one. I ended up with 45/42/30x14-16-18-20-23-26, on a Deore MT-60 crank with Suntour road derailleurs. (Superbe rear, AR front.)
After commuting on the bike for a week, I like it a lot... maybe even more than I thought I might.
My commute is only a couple of miles, but it's 2/3s flat and right on the coast, so there's always a quartering headwind, no matter which way you're going. The last half mile of the ride in is a 6-8% climb to the shop.
The 45/42 half-step really comes good on the flats, and it gets better as the wind gets stronger. Having a 7% taller or shorter gear always available and only a predictable shift away from the gear you're currently in is a big win.
The way I shift the half-step is that I start on the 42, and I stay there until I'm up to cruising speed. Once I'm at speed, I can tell whether I need that half step taller gear. If I do, I shift the front. Only rarely do I need to do the full double shift, say from 45x18 to 42x16. Knowing your legs, your speed, your conditions, and your bike are key to finding a best-for-your-bike-ridden-by-you shift pattern.
Triples are good. That 30T ring comes in handy on a Monday morning. The downshift to the granny is a double/double, but that's true of any road triple. The upshift from the granny to the middle ring is slow, and not to be done under load, but I expected that, since I'm using non-ramped chainrings and a road double front derailleur. (This is necessitated by the half-step gearing. Triple FDs can't cope with rings 3 teeth apart, the stepped inner plate hits the middle ring when you shift to the big one.) Fortunately, that's not a shift that needs to be quick, so it's not much of a problem.
The downsides are few, but there are some.
Setting up the front derailleur was a pain. I needed a shorter bottom bracket than spec so that the double FD could swing far enough out to shift to the big ring. Plus, with the 45T big ring, the FD is mounted as low as possible without snagging on the rear derailleur cable, and it still sits a bit higher than I'd like. Once set up, it's been great, but getting it there was a bit tricky.
The chain is slack in the 30x14 and 30x16. That's because of the Superbe RD, which only wraps 22T worth of chain, and I'm at 27. If I was using a 52T big ring, it wouldn't work at all.
It looks weird.
And that's about it. On balance, it's a big win.
--Shannon
After commuting on the bike for a week, I like it a lot... maybe even more than I thought I might.
My commute is only a couple of miles, but it's 2/3s flat and right on the coast, so there's always a quartering headwind, no matter which way you're going. The last half mile of the ride in is a 6-8% climb to the shop.
The 45/42 half-step really comes good on the flats, and it gets better as the wind gets stronger. Having a 7% taller or shorter gear always available and only a predictable shift away from the gear you're currently in is a big win.
The way I shift the half-step is that I start on the 42, and I stay there until I'm up to cruising speed. Once I'm at speed, I can tell whether I need that half step taller gear. If I do, I shift the front. Only rarely do I need to do the full double shift, say from 45x18 to 42x16. Knowing your legs, your speed, your conditions, and your bike are key to finding a best-for-your-bike-ridden-by-you shift pattern.
Triples are good. That 30T ring comes in handy on a Monday morning. The downshift to the granny is a double/double, but that's true of any road triple. The upshift from the granny to the middle ring is slow, and not to be done under load, but I expected that, since I'm using non-ramped chainrings and a road double front derailleur. (This is necessitated by the half-step gearing. Triple FDs can't cope with rings 3 teeth apart, the stepped inner plate hits the middle ring when you shift to the big one.) Fortunately, that's not a shift that needs to be quick, so it's not much of a problem.
The downsides are few, but there are some.
Setting up the front derailleur was a pain. I needed a shorter bottom bracket than spec so that the double FD could swing far enough out to shift to the big ring. Plus, with the 45T big ring, the FD is mounted as low as possible without snagging on the rear derailleur cable, and it still sits a bit higher than I'd like. Once set up, it's been great, but getting it there was a bit tricky.
The chain is slack in the 30x14 and 30x16. That's because of the Superbe RD, which only wraps 22T worth of chain, and I'm at 27. If I was using a 52T big ring, it wouldn't work at all.
It looks weird.
And that's about it. On balance, it's a big win.
--Shannon
08-16-21 | 06:53 PM
#2
Senior Member
Joined: Aug 2020
Posts: 1,180
Likes: 1,466
From: Saratoga, CA
Bikes: 1981 Bianchi Specialissima, 1971 Bob Jackson. 2012 Kestrel 4000. 2012 Willier. 2016 Fuji Cross 1.1, 1950 Hetchins, 194X James Fothergill, 1971 Paramount P15, 1973 Paramount P12, 1963 Legnano (x2), 1951 Hetchins, 2024 Canyon Endurace
Welcome to the half-step club! I stumbled into mine when I bought a bike with a half-step. I thought I would hate it, but I loved it. I have since converted it to a half+granny.
