CargoDane

You can't stay upright at 3.5 mph? Do you jump on your bike while walking briskly? I can easily do that - even on my Bullitt (the longest bike I own), so I can't fathom how you can't do that on a normal bike.

Carbonfiberboy 

I like this one: Bicycle Gear Calculator
Nice, easy to use graphical user interface.

Tourist in MSN

Interesting that you mention 3.5 mph and tie that to a cadence.

When I built up my Rohloff bike, I had to decide what chainring sizes to use, as your chainring choice with an internally geared hub sets the entire gear range.

For around town riding with an unladen bike I knew what I wanted for highest and lowest gears from riding my other bikes on the up and downhills, so it was easy to calculate the chainring that would give me the ideal range of gears for that kind of riding.

But I knew for touring with a heavy load that I would want the lowest practical gear that I could get that was not too low. I did some hill climbing on a different bike and carefully watched my speed while trying to decide what the slowest speed was that I could maintain vertical and directional stability without a lot of oversteer, and that speed was 3.5 mpg. And the slowest cadence that I felt was quite smooth and not jerky was 72 rpm. Then did some calculating and found the chainring size that would give me a lowest gear with a speed of 3.5 mph and cadence of 72 on 57mm wide 26 inch tires, that is 16.2 gear inches. And after several tours I have concluded that in fact is the perfect lowest gear for me.

At times I wished I had a higher highest gear to avoid spinning out on shallow long downhills, but not at the cost of giving up my lowest gear.

The stock sprocket that comes with a Rohloff hub was 16T when I bought the hub. For around town riding with an unladen bike I use a 44T chainring, for heavy loads when touring I use a 36T chainring. And either add or subtract 4 links when I change chainrings.

I am at an age where I should avoid exertion that pushes my heart rate too high. So, if the hill is too steep to keep my heart rate at a good rate while pedaling up a steep hill, I get off the bike and push at a slower speed.

Just in case others that are setting up a Rohloff read this later, I should point out that Rohloff has established minimum chainring to sprocket ratios to avoid over-torquing the parts in the hub, so anyone sizing their chainring(s) like I did should check Rohloff minimum ratios. My ratio of 2.25 for my weight is within their specifications,

CargoDane

I have a 39T front sprocket (belt, so "sprocket" is correct), and a 22T rear sprocket on my Rohloff, running on 26" wheels. The actual gear inches change if I use a Kojak 1.35 vs a 1.8 Naches Pass.
I can keep my balance on this long bike almost to a stand still. Sometimes, I can even do a stand with it, despite its long wheelbase. I can't fathom how you guys can't on normal bikes. You can't go, say, 2mph without weaving? Not even up steep hills?

Tourist in MSN

Your ratio is 1.77, Rohloff sets a minimum of 1.9 for most cyclists. I hope you do not need any warranty work on your Rohloff. Click on it where it says - Smallest permittable sprocket ratios
https://www.rohloff.de/en/service/handbook/faqs

If you can easily ride at 2 mph, you are probably the only one.

CargoDane

It's fine.

Nah, It's just that I don't find it difficult at all. Maybe because I used to bike trials? But, really, you can't even do 2 mph up a steep hill without weaving on a normal wheelbase bike? Or even 3?
I find that very odd, to put it mildly.

EDIT: I just looked, and it is not actually a 22T I have (for some reason I thought it was). I can see from looking up my order that it is actually a 19T on the back. And the one on the front is 46. I have no idea why I thought it was 39/22. So not quite as high strung.

CargoDane

Here, from my order overview:

staehpj1

I dunno, but I used a 39/26 with a 12-28 for a tour on the Southern Tier. It worked out fine for me with an ultralight camping load. FWIW, the 39/26 was a triple with the big ring removed. It was on an old 1990 Cannondale crit race bike that I decided to tour on. I had other choices including a dedicated touring bike, but I chose the Cannondale and enjoyed it.

It had a range of about 25-88 gear inches.

Digger Goreman

Thank you many times for this. I run the same triple and 11-34 rear. Always wondered, when the day comes, if it would tour well. Your post gives me confidence.

Tourist in MSN

3 mph, not a problem but is not very smooth. 2 mph, no.

46/19, no warranty problem, that is a 2.42 ratio that is within Rohloff specifications. For touring, my ratio is 2.25 and for riding near home 2.75. Your ratio with 26 inch tires puts you in between the ratios I use.

If you pedal your bike at a cadence of 39 in your lowest gear, that is 2 mph.

CargoDane

I sometimes pedal slower up steep hills with a lot of load. I think that's key. Uphill makes it easier to go slow. When I say "I can't fathom why people can't go 3.6 mph or slower than that without weaving", it is not something I say rhetorically. I seriously don't get it.

Anyway, I really have no idea why I thought the 39/22. I think I have that on my other cargo bike (chainrings), or I may have just calculated it at some point, and it somehow stuck in my head.
I know for a fact that sliding dropouts can be used with a 22T sprocket and in principle a 16T sprocket without swapping the belt too (there's room either way for it to slide in place).

djb

sorry if I've already responded to you about this in the past, cant recall.
My 26n bike with 44/32/22 and 11-34 works just dandy for touring. Having the 44 and the 11 gives a 104 gear inch top gear which I spin up to a bit over 50kph or 30mph, but of course have descended on this bike up to about 80k or 50mph, but pannier wind resistance generally keeps top speeds to 60, 70k.
The really only downside to my setup is that if unloaded, or lightly loaded, I sometimes have to change between the 32 and 44 more often, but generally with any touring load, it works really really well. A 700 wheeled bike would give you a bit higher gearing, which would be nice lots of times, but to repeat myself, after a number of years using this bike on tours, I am really happy with the setup and its great to have for any short or long steep hills. The 22 ring is fantastic for this and once in a while I think to change the 11-34 to a 12-27 or whatever to have closer shifts, but invariably there are some short steep little bugger of climbs where Im just plain glad to have the 11-34 on all the time.

mbailey

On my gravel bike with 650B X 47mm tires, I run 1X11 shifting with a 34T chainring and a 10X42 cassette. Even unloaded, I only spin out on a fast descent and can pedal on flats up to 22-23 mph.

rifraf

Yes Rohloff says:

To prevent overstraining the hub, a minimum sprocket ratio of 1.9 must be used. With the available sprockets these minumum possible sprocket ratios are:
chainring/sprocket: ~40/21, ~36/19, ~34/18, ~32/17, ~30/16, ~28/15, ~28/14, ~26/13 (ratio 1,9)
belt sprocket: 39/19, 39/20, 42/22, 46/24 (ratio 1,9).

This resembles a derailleur transmission of 20/40. Larger chainrings can be used without exceptions.

I decided the 34/18 would suit my needs best

Thanks for the link

dgodave

34x11 would work ok for me as a high gear. I might get "pedaled out" on descents tho. What crankset is it? Can you get a 38T ring for it?

I seem to choose exceedingly hilly areas for touring and I neeeed a low low gear, So I wont compromise that.

staehpj1

That isn't necessarily a huge deal though. Two anecdotal experiences...

First, I found that with a little higher gear (39/12) than that on one tour I just spun it up to a real high rpm at the top of the descents and coasted. I found that to be just about as fast as pedaling all the way down at a normal cadence in a higher gear. In any case it wasn't a big deal since it is a tour not a race. I still made a number of 100+ mile days that tour and average decent mileage.

Second, on another tour (800 miles, lots of short climbs, 1 mountain pass) I had a more laid back approach and for no apparent reason just rode in the middle ring (34t) for the whole tour. That was with before I went UL and was with a moderate load. It was just fine. That was with an 11-32 cassette.

Tourist in MSN

I have 11-32 cassettes on most of my bikes, it simplifies spare inventory, they are common to buy, works well with a wide variety of equipment. I think I have three 11/32 spares on the shelf right now.

Happy Feet

Funny to read this discussion today, as I am currently debating a build decision regarding gears.

A few years ago I began building a serious hill climber out of a rigid mtb that eventually uses a 42/32/22 with an 8 sp 11-40 cassette. The top end doesn't really bother me as it was more of a heavily loaded touring bike and my aim was to go as low as I could go (I have a higher geared light touring rig). Now it has a suspension fork and is used as a geared 26r mtb but is mostly redundant as I have a low geared fatbike for that same purpose. Another converted mtb build has 42/24 with an 11-36 cassette and it turns out that frame fits me just a bit better so I am now turning it into my loaded touring bike, as a winter project.

Decision: whether to swap the triple drive train over, that may require swapping the BB as well (a pita) - or just the rear end, making it an 42/24 by 11-40. How much will I miss that middle ring?

First world problems...

djb

As you say, 1st world but hey, we always like a gearing discussion don't we?
I think the issue of missing the 32 is more about riders, you're clearly a stocky legged Massey Ferguson engined sort of guy. I'm a two stroke engine sort of guy and from experience, I'd both miss the 32 and find the 42 just too tall a lot.

but that's me

dgodave

Anymore my tours have a very laid back approach. Maybe tons of climbing, but no need to keep up with a fast group - or any group at all.

This might seem crazy to some people, but when I toured Japan on my Brompton I had a 22 - 66 gear-inch range using the Brompton 6spd system. Worked fine for me.

Happy Feet

I think that might be an accurate description of me

I know I'm going to do it but not looking forward to tearing both bikes apart because I already like the way both perform; but the triple mtb is redundant and I am committed to reducing my fleet (a bit).

Was thinking of renting the Haldron collider for an hour or two and seeing what happens when I send both bikes through... maybe a tandem with really low gearing!

djb

It'll probably work for you, but the 18t jump is a lot. I used 16t jump a lot but it was annoying at times.
guess try it and see.