djb

https://cyclingabout.com/gear-ratios...-bike-gearing/

Well written, good balanced and realistic take on real world use of gearing for various riding and types of touring vis-a-vis load, terrain and rider strength.

Will save this link and recommend it to people to get a week informed view on gearing.
Only thing I would have added is a bit more pro triple points, but all in all this is a great intro and informative article to folks coming into touring with little real life experience.

imi

Yes, thanks djb, a good article.

The part that stood out for me was:

"In the western world, it is becoming harder and harder to obtain high-quality spare parts for 7, 8 and 9-speed, however in the rest of the world you probably won’t find any 10 or 11 speed spare parts!

If you’re off on a big adventure through remote areas of the world, I recommend using a 9-speed drivetrain due to part availability. It is much more likely that you’ll find chains, cassettes, chain links and chainrings."

I'm putting together a 9-speed expedition bike for this reason. Sourcing 9-speed parts has not been a problem online (CRC), so I'm wondering if it's LBS's in the western world that are cutting back on their 9-speed stock?
OTOH I'm sticking to MTB gearing 44/32/32, 11-28, not the wider range 'touring' cranksets mentioned in the article, so maybe that makes a difference...

fietsbob

new this year Rohloff re designs their cog to be simple to replace in the field , with a snap ring and a screwdriver.

though their spline pattern is their own (in 13 splines to match their smallest cogs 13teeth, and all the larger sizes.)

so a flat cog is cheap to mail to you & now the chain-line for the 13t cog is the same as all the larger sizes, [ It was wider ]

too bad they didn't just use the 3 speed spline pattern .. used universally for a really long time. & cogs are Cheap.

djb

What I agreed with overall was his take on what gear inches for a given type of touring situation, and that for an "expedition" type tour (tougher roads, steeper gradients, probably more weight on bike) he suggests 18g.i as this reflects my experience.
I too agree with the 9 speed view, and I would go that route also, 10 for trips around here. Like you I would go mtn bike crank also, 44/34/22 would be my preference, and cassette wise, would depend on the trip.
It's just too bad there aren't common 9 speed 12-30 or 32 cassettes that don't cost an arm and a leg. I'd go 26in for off and beyond, and would want about 18gi so a 30 would be a minimum.

Buffalo Buff

This is one of the things I love about using ultralight setups. This isn't something I've ever had to give any thought to. I'm using the stock groupset that came with my road bike (Compact double, 10 speed Shimano 105) and it's served me without fail. Fully loaded through the mountains? No problem. Flew up hills I crawled up on my heavier mountain bike setup, despite the latter having a more typical touring style gearing with a triple uo front etc.

djb

Fiets, yes I've read journals of folks having to take some special tools (wrench?) to remove replace the with cog in the back (flip it at some point). Seems to me one guy had a machine shop guy cobble up a one off tool in some far off country.
Never seriously considered a rohlof but they are neat doodads.

djb

And that's what I found useful was his views of what gearing for a given bike+load weight, I personally prefer a bit lower than other people, but it's a pretty good reference point for someone with no experience.

Tourist in MSN

In general I agree, a good piece. But I have a few comments:

Every time I try to explain gear inches to someone, they have sort of a vacant look on their face. It is only when I say, pretend you are on a unicycle, your pedals and crank is fixed to the wheel with no gearing. The diameter of that wheel in inches is the gear inches. A big wheel makes it hard to go up hills, small wheel much easier to climb hills but slower top speed. Then they grasp the concept of gear inches really well. I think the author should have tried to explain gear inches more like that. (Note that I did not say the concept originated with a Penny Farthing, nobody knows what that is any more.)

Then once the concept of gear inches is understood, I think they could have elaborated more on how you calculate a gear ratio, why you might not have as many gears as you thought (redundant or duplicate gears), how you should avoid cross chained gears, etc. I thought that it was a bit too focused on the latest hardware, not enough on what kinds of gear ratios you would want to climb what grades, etc. I think the typical person that would benefit from a piece like that will not get a lot of benefit from knowing that square taper and external bearings both exist, that is what I mean by a little too focused on the latest hardware.

I have no trouble finding parts like chains, etc., for Shimano eight speed systems.

They say a long cage MTB derailleur accepts a cassette up to 40t. I do not think my old M739 XT rear derailleur would handle a 40T cassette, I am not sure what they are trying to say here - unless they are only talking about the latest hardware.

They were inaccurate on the minimum gearing on a Rohloff if you weigh less than 100kg, it is 1.9 where they cite 2.5 for all riders.
Sprocket ratios: www.rohloff.de

But overall, not bad.

bradtx

djb, Thanks for posting the article.

It pretty much follows along with the advice I received when I built up my first touring bike and have found to be spot on in practice. I liked the points made about individual gear spacing as well as the usual overall range.

Brad

robert schlatte

+1. 8 speed components are cheaper, too. I have been running SRAM 8 speed chains and cassettes. I wonder if I need to stock up a bit?

djb

7 and 8 stuff is very easy to find, imo no need to stock up, there are loads of 7 8 speed bikes still sold.
I have recently replaced 7 sp stuff and my 8 sp bike gets new chains and cassette once in a while and kmc chains for me work well.

djb

Tourist, I think it's fair to say that the glazed look is always going to be the case, but maybe it will stuck in someone's craw and help them at some point.
And yes, making a simple gear inch analogy is good, I tend to at least try to impress that having a black and white number for no matter what the bike, double, triple, and for whatever weight of bike/load is a good thing.
Knowledge is always good and can go beyond hearing a salesman's assurance that "yes, this bike will be fine for touring...."

djb

As a reference of my experience, his suggestion of 10kg (22lbs) of stuff to use 25gi is OK but with steep hills I'd prefer lower, closer to 20 but then I'm not 25 anymore and knees can be a bit crotchety at times, so lower than 25 doesn't have a downside to me in this situation. If I use the lowest gear a few times it will be worth it and having it will not affect my average speed at all, nor how far I take a downhill, but the knees will appreciate it and frankly, being easier on the knees on steep climbs will mean my legs and knees will be in better shape for all the other riding,so I will be faster and more comfortable, less sore than with higher gearing.

imi

Yeah, but would you take that set up on a multi year RTW tour including crossing siberia, the himalayas and mongolia?

Seriously, we get the UL thing, but it's not the be all and end all of touring.

Buffalo Buff

No. If I were going to tour somewhere where off-roading is more frequent, or road conditions are much worse the North America, I would bring the appropriate equipment


Ok? Never said it was?

Tourist in MSN

I find that I always use my lowest gear on a day with hills, but sometimes that lowest gear is needed and sometimes it is much lower than I really needed and I only used it for a respite.

Yeah, I concur, the evangelicals for UL can get a little tiring.

djb

with 25g.i. when I have one pannier of stuff, so bike at about 30, bag at, I dunno, 10lbs maybe, I very regularly use my low gear at 25g.i when going up certain hills. When I have that same bike set up for about 21g.i. I tend to have more weight, and I still use it regularly.

As I brought up earlier, and as you mention "using it for respite", I really do notice that having a lower gear than you perhaps need for a given moment can allow your knees a little break. Now I can only speak for myself about my knees, but depending on what riding shape I am in, and how my knees are on a given day, being able to reduce the amount of forcing I do with them really does translate into them being better overall for the rest of the day. Don't want to exaggerate this, but having a little break sometimes and spinning a bit more than you really need is just plain nice for leg muscles and knees--but again, thats me (but suspect this is a general thing for everyone).

and as for going fast downhill--this is where in my experience it really doesnt make much of a difference. Sure, there will be some big long downhills where a really tall gear is nice, but even on my 26in mtn bike with a 42/11, I can easily pedal along at 40kph, and to be quite frank, the times that I can hold 40kph (25mph?) for any length of time are far and few between.

and when we talk about real speed, it will always come down to ones experience with speed, being comfortable at speed, and being both comfortable and competent in taking corners fast on downhills. Any descent that is that technical that speeds consistently get up very quickly, I figure I can get down a steep, twisty downhill as fast as most on even a 90g.i bike, because when we are talking serious speed, over 70kph, its not about gearing, but assessing the conditions and keeping momentum and taking corners properly.

And the times I have gone really fast, its been on bikes that spun out nearly 20, 30 or 40kph earlier.

SHBR

Ugh, gear inches, I prefer to know what speed I can travel at 90 RPM. I find that much more useful and easier to remember and explain. Anyone who has driven a car with a tach can easily understand this concept.

For me I use a low gear that is somewhere between 13-15km/hr@90rpm, and a high gear of about 30-35km/hr@90rpm. If I were to encounter extreme terrain, a lower gear that can sustain 6-8km/hr@90rpm may be necessary.

djb

I guess if that is what works for you, the main thing is to compare diff settings to something that you know works for a given load/terrain, or doesnt , and then you adjust for that.
I learned about gear inches about 25 years ago, so that is what I know and is a good reference to gearing changes that I have done in the past and relate X number of g.i. to various terrains that I have toured on.

also, i have never had a cadence bike computer, so am not really familiar with what X cadence feels like in terms of numbers, as I dont really know what my natural cadence is or in diff situations. I have however spent lots of time climbing at 6-9kph but have no clue of what cadence I was pushing.

ModeratedUser

Great article, but the one thing the author failed to explain is the relationship of inches to rpm. For example; "On a touring bike, 18″ is a great low gear and 113″ is a good high gear." 18" = one rpm of the crank, and 113" = one rpm of the crank.

Leebo

Looked at shimano xt or deore mt cassettes ? Amazon has a sram pg950, 11-32 for $29.00.

cyccommute 

I'm going to be different and not praise this article. It has a number of problems that are fairly common in this kind of article and continually bug me.

First

Sure, new cranksets permit a wide spread of gears but they are poorly selected and almost impossible to shift smoothly. The wider the range the worse the selection. For example comparing an standard 50/34 double with a 48/34/22 (both using an 11-34 cassette), it can be seen here that the double doesn't have anywhere near the range of the triple.

Sticking with the same cassette (since the triple can use the same cassette as the double), if the range of the double is matched to the triple, you can clearly see the shift pattern becomes nearly impossible. If you are riding in the 50/15 in this combination and need to shift down, dropping to the 22 (a nearly impossible shift) drops the speed from 24 mph at 90 rpm to 11 mph at 90 rpm. Increasing to 120 rpm (an uncomfortable rotation for most people) only rises the speed to 15 mph. It would feel like the bike has dropped the chain and many people might even stop to check which loses an momentum you might have had to begin with.

If you try to make the transition more comfortable with a lower high gear by going to a 34/22, the ratios are still problematic for a double. Now you have a fair low but the high gear is too low. Having ridden mountain bikes in the early days before freehubs with 44/13 high gears that result in a 90" gear in the past, I can tell you that that low of a high gear becomes frustrating quickly. You have to start coasting just a bit over 25mph which can mean a long coast downhill. I've never found that coasting for long periods of time is preferable especially when the world turns upward again.

I also question his "expertise" to tell anyone other than himself what gear ranges are "enough" for the "average rider:

Quite frankly, his low gears are too high by several inches in all cases. I'm not a "weak" rider and I could probably suffer my way up a hill with a 20" gear on a loaded road touring bike but why should I? I can be strong and stubborn or I can be strong and smart by choosing a gear that is much lower than 20" for a loaded bike. I've toured in the Appalachian mountains where the roads are much steeper than they are here in Colorado with 17" gear (22/34) and a 15" gear (20/34). I could ride up more hills with the 15" gear then I could with the 17" gear. I know there is no shame in walking a hill but there's no joy in it either.

As for off-road touring, an 18" gear isn't even close. I've had to walk many miles off-road here in Colorado where our jeep trails don't comply to the "normal" 5 to 7% grades of our paved roads. I'd have had to walk further with an 18" gear. I don't even ride unloaded with an 18" gear and still can't ride everything that our Colorado mountains have to offer.

I've never found that I was hunting around for "that perfect gear" while touring...at least not while cruising on "flat" route. I've seldom found a route that was truly "flat" as well. I've found that I can deal with not having "that perfect gear" for maintaining cadence far better than not having a low enough low. One is an annoyance and the other will put you on your feet.

djb

Ive used the 9 speed 11-32 a lot, and always would prefer a 12 to something. Hardly ever use the 11 and when I use a 12-27 9 spd, I really like the 12,13,14,15....
This is personal, but I would much prefer a 12,13,15,17 etc sort of range, as those are cogs that get used the most all in all, and I will always prefer an added 13 rather than a 11.

in the past, when i have looked for 12-whatever, they seem all to start at 11.
there is a nice 12-30 10 speed that could work well with a mtn crank, 22 or 20, but more than a 30 would be better.

djb

cycco-I expected you to pop in.

I figure you and I and perhaps others need to get together and write a new article on touring gearing bringing up all the things that bug us here.

As was brought up right from the beginning, the "glazing of the eyes" factor has always to be considered, and when I saw this article, I found that it did a pretty good job of presenting the whole issue in not too boring a way.

Yes, I agree with you on how low is good for each bike+load thing--thats why I brought up my experiences riding with about 20-100 gear inches and how I felt his numbers are too high.
I do however agree with if its possible, to have as tight as a cassette as you can, I still hope to set up a tourer with a good compromise of as tight a cassette as I can run (hence the 10 speed 12-30 mention) but if its not possible, at least not to have any bigger jumps than I have ridden with a lot (Im thinking specifically the 9sp 11-32, and how it would be great to have a 12-whatever--will have to do some searching again for whats available in 9 spd in this range, but that doesnt cost $150 or whatever.

and yes, of course I feel that a well chosen triple is always going to work better, with the majority of the time being in the midring, for me a 34 or 36 tops is what would work best (coming from riding bikes with 32t and 39t midrings). Less heavy load, 36 would be good, but for heavier load, easily a 34.

chasm54

@cyccommute
Opinions differ. I thought his suggested ratios, at least for on-road touring, were pretty much on the money. Heavily loaded (which for me is a 36lb expedition tourer with 40lbs of baggage) I have found a 19 inch gear to be low enough. On a lighter 28-lb bike with say 20lbs of stuff, I can get by with 25 gear inches.

I absolutely agree that a triple with tighter ratios at the back is the way to go unless one has a Rohloff.