sd5782 

I have been waiting to find a Sugino Mighty Tour 110 bcd for cheap to put on my 83 Trek, but no luck. Go figure. The Superbe 144 bcd that was on it is superb, but the 42 ring low in front is not as friendly to an old guy even in the flatlands here. I have numerous 6 and 7 speed free wheels including a 14-32 six speed I had on it. That 35 inch low was good, but I always wanted a bailout gear.

I came into a SR Apex 86 bcd and thought of trying it as a 34-47 and was looking at the gear charts. Nothing really matched the free wheels I had too well. I then plugged in a Shimano 14-32 5 speed from a bike I worked on for my sister. I turned that from a 3X5 into a 3X6, so go figure. The 2X5 with the 34-47 front setup looked very interesting as a 1 1/2 step, so regress I did. I would post a bike calc screen shot if I knew how. 700x32 tires and 14, 17, 21, 26, 32 freewheel with 34-47 rings if interested FYI.

I took a 28 mile ride and ???, well maybe? I shifted less, but definitely knew when I needed a different gear, and knew it was THE RIGHT gear when I got to it. Less gratuitous shifting for a slight up or down incline, and gears for the 11-18 mph I do on the flats depending on wind and such. Old guy here, so feel free to ridicule. Seems silly I guess to go backwards. I even got used to double shifting a bit and think I may try it for a bit. If nothing else, it keeps idle hands and minds busy.

rustystrings61 

I went through a similar thought process with the 2x6 setup on this year’s Clunker Challenge entry, an ‘86 Cannondale with 40/52T and an old 14-28 6-speed Shimano freewheel. I guess I could go to a 7-speed freewheel but what would I do, realistically, with a 52x13?

I remind myself that variable gearing can be a luxury, especially since I’ve ridden primarily fixed-gears for the last 15 years or so. A 2x5 is wonderful and millions of us rode millions of happy miles on bikes so equipped.

repechage

With 5 cogs to choose, you either grunt a bit more or spin a bit more, depending.

sd5782 

Actually not an excessive amount of grunting or spinning. Bike calc showed 8 evenly spaced gears between 9.5 and 20 mph and my ride reflected that. Tempting enough to give it a bit of a try. If I had hills and was younger and hit the mid 20 mph range it would be a different story.

Bad Lag

My bike is also 2X5, so I'm in no position to ridicule you. It shifts beautifully and has all the gears I need for my locale.

My 2X5 = (42, 52) X (14, 16, 18, 21, 24)

John E

That was very common stock gearing in the 1970s. The large and small chainring ratios mesh well, and you have both decently wide range and 6-7 percent ratio development except at the very top and bottom.
I did the 1972 Los Angeles Wheelmen Double Century on a very similar 54-44/14-16-18-21-24, which I copied from the then-new Nishiki Road Compe.
I find I really need a 2x6 to get me the range and gaps I crave, in either a 1.5-step or a half step, so I currently run:
50-42/14-16-18-20-23-26, 46-38/13-15-17-19-22-25, and 45-42/13-15-17-20-23-26

xroadcharlie

My fist road bike came with 2 x 5 speed gearing. The 10 speeds where all properly spaced. My next bike had 2 x 6 speeds, I thought even better. Ha...5 of the 6 gears where pretty much redundant leaving me 7 usable gears out of 12, And they where spaced wider then the 10 speed. My 2018 Giant Sedona has 3 x 7 speeds. Of the 21 speeds, 12 are properly spaced. The others are either redundant or too big a step (24T - 34T) to be practical.

​​Probably 95% of my recreational riding is covered with 5 gears from 49 -78 gear inches. That translates to 14 kph @60 rpm to 26 kph @70 rpm. The hills around here are either too short or have a low enough grade to climb with these gears.

A simple 1 x 7 speed properly spaced (13, 15, 17, 19, 21, 24, 28T) which is about 40 - 87 gear inches w/42T chainring might work well for many folks. That would cover about 11 kph @60 rpm to 33 kph @ 80 rpm.

Bad Lag

A pair of chain whips (inexpensive) and some spare freewheels will usually allow you to tailor the gearing to your needs.

sd5782 

That gear calc website is kinda addicting.

Bad Lag

I built a small spread sheet that I use. I gives numbers and graphics.

canklecat

Even as a yoot in my teens and twenties riding a 10-speed Motobecane Mirage I had to make concessions to the San Diego hills. They weren't long but many were remarkably steep. After I gave up on racing crits and time trials I looked for alternatives to the closely spaced gearing I'd been using.

I finally brewed up my own freewheel, with no more than a two-cog jump between the smallest and middle cogs, a bit more for the fourth cog, and something like a 25 or 26 for the biggest cog to bail me out on those 10%+ short, steep climbs. I may also have gone with a slightly smaller inner chainring, although options were limited. Shifts were sometimes awkward, losing momentum due to less-than-smooth transitions.

Only way I'd choose a 5-speed freewheel now would be for flat terrain, and I'd go with a corncob or as close to it as I could get. My 63 y/o engine can't handle much more than that.

Seven speed really seems to be the sweet spot all around, and accessible to most C&V bikes.