Shouldn’t personal computers radically change the way we evaluate bike gearing?

[RPS]

I get that in ancient times before personal computers a system of inch-gear made a lot of sense because it had to be very simple, and since guys had to do the arithmetic with pencil and paper (unless they knew how to use a slide rule) one simplistic table could be applied by everyone to their specific bike by crunching some additional bike-specific numbers. But doesn’t that seem outdated today when we can process a lot more meaningful information instantly and without effort? Why not just go directly to what we want to know in terms that have more direct meaning to us? Whatever that may be in your personal case.

As an example, these are a few of my personal “must haves” when gearing a bike:

1) I want to know if I can hit 40 MPH while pedaling at or below 120 RPM.

2) I want to know if I can ride around 18 to 22 MPH at 90 RPM with fairly straight chainline.

3) I want to know if I can climb at 5 MPH without my cadence being so low I will fatigue muscles too quickly.

4) I want to know if a typical ride I may do will force front chainring shifts too often.


Notice that inch-gears or no other system is required to describe what I’m after. It’s all directly about what speed I plan to ride and what cadence I’m willing or prefer to pedal. Why not let the personal computer do the work and save me a bunch of middle steps?

[Mark McM]

I get that in ancient times before personal computers a system of inch-gear made a lot of sense because it had to be very simple, and since guys had to do the arithmetic with pencil and paper (unless they knew how to use a slide rule) one simplistic table could be applied by everyone to their specific bike by crunching some additional bike-specific numbers. But doesn’t that seem outdated today when we can process a lot more meaningful information instantly and without effort? Why not just go directly to what we want to know in terms that have more direct meaning to us? Whatever that may be in your personal case.

I'm not really sure what you are after here. Even with a computer, gear-inches (or their equivalent) still have to be calculated. Evaluating gearing for most personal requirements may require additional data which may be more difficult to acquire (such as - how much power does the rider produce, and for how long), or may be impossible to quantify easily (what is a "typical" ride?).

As an example, these are a few of my personal “must haves” when gearing a bike:

1) I want to know if I can hit 40 MPH while pedaling at or below 120 RPM..

You need a gear of at least 112 gear-inches.

2) I want to know if I can ride around 18 to 22 MPH at 90 RPM with fairly straight chainline.

You need a sprocket in the middle of the cassette that gives a gear size of 67 - 82 gear-inches.

3) I want to know if I can climb at 5 MPH without my cadence being so low I will fatigue muscles too quickly.

No computer can figure this out unless you tell it how steep the hill is, how much you (and your bike) weigh, how much power you can put out over the duration, and how slow you can pedal without your muscles fatigueing.

4) I want to know if a typical ride I may do will force front chainring shifts too often..

I'd really like to know how you intend to quantify a "typical ride" in a way the computer can understand.

[flydhest]

http://cycleseven.org/bicycle-gear-inch-calculator

There are sites like this that have all the info you asked about. This is just one that came up first, I'll try to find the other one where it was actually more catered toward what you are asking about.

[false_Aest]

journey/destination.


i don't think i've ever ever thought about gear inches unless someone brought the topic up. when they did, i consider it, do a quick ratio thought (53/12 vs 54/13) and then start humming the Breeders.

think you could harvest the data you need. watts, incline, etc

but how do you enter data like: i had 3 beers on tuesday, pooped twice on wednesday and didn't get to sleep until 3am because I had sex with my wife 3 times ???

[Lifelover]

Like Mark, I'm not really sure what you after here either.

Even with the equations preprogramed into a computer, enter the data (variables) into the program would be every bit as complicated as crunching the numbers.

If you have the most basic understanding of the math involved it is really very, very simple.

If you do not have (or care to have) the basic understanding of the math, I don't think you would be able to "ask" the program the right question.

I really think you are over complicating something, I just don't know what.

[flydhest]

I think what he is talking about is that suppose you know of climbs, you know you may be down at 5 mph because it is hard and steep. What gearing would allow you to keep rpms above 75?

1) is a straightforward question and the site I cited will answer it for specific gearing choices.
2) Sheldon's calculator lets you look at a whole cassette. The answer to this question is will the gears I select at the rpm I want mean that I am in the middle of the cassette or the bottom/top
3) see above, also straight forward. At 5 mph and some cadence that I think it the lowest I can turn and be comfortable (say 75 rpm) what gearing do I need?
4) I don't think I get, but that is because it is in terms of a specific set of rides the OP has in his head.

[Bob Loblaw]

I don't mean to be disrespectful, but I don't understand what any of these questions have to do with riding a bike. I could see myself occasionally looking at a gearing chart when offering advice (e.g., "Yes, a 28 x 28 is smaller than a 34 x 32 and you could use your existing cassette, but you'd need a new BB, FD and triple crank"), but that's about it.

BL

[RPS]

I'm not really sure what you are after here. Even with a computer, gear-inches (or their equivalent) still have to be calculated. Evaluating gearing for most personal requirements may require additional data which may be more difficult to acquire (such as - how much power does the rider produce, and for how long), or may be impossible to quantify easily (what is a "typical" ride?).



You need a gear of at least 112 gear-inches.



You need a sprocket in the middle of the cassette that gives a gear size of 67 - 82 gear-inches.



No computer can figure this out unless you tell it how steep the hill is, how much you (and your bike) weigh, how much power you can put out over the duration, and how slow you can pedal without your muscles fatigueing.



I'd really like to know how you intend to quantify a "typical ride" in a way the computer can understand.
Why? Why do I need inch-gears or its equivalent at all? That’s the point I’m questioning. It hit me a while back that the “inch-gear” system seems outdated. Also, I'm not trying to make this complicated by adding power and other factors that are not necessary and way too complicated for most riders to take into account.

Why continue to use an archaic system like inch-gear which was obviously set up to make calculations less tedious based on computational limitations of 100 years ago when today’s technology circumvents that need entirely? My basic question is what information are we really looking for when evaluating bicycle gearing?

For example, I’d guess most of us ride with constant cadence and/or speed data; so don’t we relate to that best? After a ride our bike computers tell us our maximum speed, what our average speed was, maybe what our average and/or maximum cadence was, and we probably even recall very clearly what our minimum speed was while climbing the toughest hill on the route we just finished. So (in my particular case which I think is typical of many riders) why should I really care about inch-gears when I’d have to convert it back to speed and cadence in some way for it to have the significance I’m looking for?


For what it’s worth – I’m using myself as an example in stating that bike speed as a function of gear and cadence is what I’m interested in. I’m not suggesting at all other riders should be interested in the same data as I am. However, whatever data a rider wants, why not set up a spreadsheet or whatever works for you that gives you that data directly on a PC instantaneously. And if you don’t like what you see, just try another set of data numbers and get another answer instantaneously. That’s what personal computers can do, so why rely on a 100-year-old system meant to be used with pencil and paper?

I hope that makes sense. Maybe it doesn’t.

[RPS]

I don't mean to be disrespectful, but I don't understand what any of these questions have to do with riding a bike.
Then why does bike gearing come up so often on this forum? :confused:

Is it we do a bad job at evaluating, riders can't relate to the way it's done, don't understand it, etc...?

[palincss]

I don't mean to be disrespectful, but I don't understand what any of these questions have to do with riding a bike.


They have to do with selecting drive train components and setting up a bike. Obviously, if you're of the school that says "just take it as it came from the LBS and go ride it," then all these questions are irrelevant.

[Pete Serotta]

Helps one get to a certain RPM,

Speed is then determined by gearing. They are mutually interactive.

One gear point is for top speed and another gear point is for a certain climbing requirement.

** Experience and knowing your strengths and also non strengths help you fine tune gearing for your requirements.


Gearing of the TDF in many ways is the same for everyone and in a few ways not exactly the same based on ** line above.

Conditioning helps everything............... :banana:

[palincss]

Why continue to use an archaic system like inch-gear which was obviously set up to make calculations less tedious based on computational limitations of 100 years ago when today’s technology circumvents that need entirely? My basic question is what information are we really looking for when evaluating bicycle gearing?


Just because something's been around for a while doesn't make it "archaic." (Sex has been around for a long time, too, and you don't see anybody clamoring to give it up and replace it with something more "modern," do you?) Gear inches -- and development, if you like it metric -- provide a way to compare gearing independent of wheel and tire size. For example, what chain ring and sprocket combination would you need to have on your Bike Friday to give you the same high gear as you have on your road bike now?

[RPS]

Just because something's been around for a while doesn't make it "archaic." (Sex has been around for a long time, too, and you don't see anybody clamoring to give it up and replace it with something more "modern," do you?) Gear inches -- and development, if you like it metric -- provide a way to compare gearing independent of wheel and tire size. For example, what chain ring and sprocket combination would you need to have on your Bike Friday to give you the same high gear as you have on your road bike now?
IMO that’s very limited information that means next to nothing to most riders.

I get that it’s easier to communicate to another rider that our top gear is 100 inches since it only takes one number, but when it comes to evaluating our personal needs it seems like it doesn’t do much. Granted you can compare one bike to another, but if you are looking to ride in different terrain or conditions then how do you compare a "new" number that has little meaning?

Ask an average rider if he prefers a top gear of 90 inches or 110 inches and I’ll guess neither number has much meaning. Ask him up to what speed he wants to be able to pedal his bike and I’m guessing he’ll give you a MPH number right away. And if he's been riding with cadence ask him how fast he likes to spin and he'll be able to give you a quick answer as well. Inch-gear not so much IMHO.

[Dave]

I've got an Excel program that gives me the bike speed at any given rpm, with any gear combination. Works great. Someone e-mailed it to me years ago.

Of course the formula is not hard to figure out.

Long ago I wrote down this formula, using tire diameter in inches: Pi x tire diameter x (60/12) x (chainring/cog) x rpm /5280 = mph

The excel formula would just have a metric conversion for tire diameter.

I never give any thought to gear inches.

[Lifelover]

Does Sheldon Brown's gear Calculator do what you want or is it missing something.

http://sheldonbrown.com/gears/

It produces a chart that looks like this.




I can not imagine dumbing it down any more and it still being in anyway useful.

[palincss]

Ask an average rider if he prefers a top gear of 90 inches or 110 inches and I’ll guess neither number has much meaning. Ask him up to what speed he wants to be able to pedal his bike and I’m guessing he’ll give you a MPH number right away. And if he's been riding with cadence ask him how fast he likes to spin and he'll be able to give you a quick answer as well. Inch-gear not so much IMHO.

YMMV, obviously.

I find your criteria of pedaling < 120 rpm @ 40 mph to be inconceivable -- but then, where I live and ride a hill is almost always less than 0.6 mi in length, and the fastest you can go before you run out of downhill and have to start climbing again is around 34 mph. I know from almost 40 years experience exactly what 96-100 gear inches means to me. The same is true for low gears. As for cadence, I had a cadence meter for a few months back in 1991, but got bored with it, and when it broke I just removed the pickup from the bike.

[ultraman6970]

Same experience here palincs, With the time u know exactly how the gears go, I do my calculations in my head but since im not racing I wouldn't care less anymore. Besides racing world is so tough that what ever u pick it might be or not right. But for a weekend warrior or newbies in racing is not even that important, because or you lack cadence big time and you lack power all together.

Why the guys in the TDF are able to make such a high speeds? well they can ride at 120 rpms using 53x14 with headwind just like it was butter. For that u have to have high cadence and be very very strong. Non weekend warrior will do that, weekend warriors concentrate in power and leave the cadence behind, thats why many of them are too worried about the cassette ratio because they can't compensate the lack of high cadence with the limited amount of power they have. Been there done that, stopped using my bike computer after a week, worthless but i give you that I would love to put it back only because of the time (i dont have a watch) and distance, wouldnt care less about the other features :D

[pavel]

To the OP - why do you need this information while you're riding?

[rustychisel]

yes, gear inches are archaic, but they're a useful way of indicating what you're thinking and what you need to ride effectively.

Miles are archaic, too, BTW.

The old guys who knew about these things used to say get the gearing you think you can handle then drop it by a couple of cogs. (eg if you think you could push an 11~23 block put a 25 on the back). Saved my arse a couple of times.

[PaulE]

We don't need to convert the gearing on our safety bicycles to the equivalent penny farthing front wheel diameter any longer, but gear inches as a concept has survived. Most of us probably just figure out what works for us and don't talk in terms of gear inches.

Here are 3 more useful websites, the last one will let you download an Excel file to play with:

Bicycle Gear Calculator (http://www.machars.net/bikecalc.htm)

Gear Inch and Shifting Pattern Calculator (http://www.jbarrm.com/cycal/cycal.html) You can work out cadence vs speed, duplicate gearing, input the cadence range and intervals, etc., here.

Gear Calculator (http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3521)

[Pete Serotta]

as usual very helpful and good for Manhattans on out next visit... :beer:

PETE

[flydhest]

Uhhh, if you live in Alexandria, then I have to differ with the assertion that doing 40 is inconceivable. I have hit 50 around here on multiple occasions.

Have done the 34 that you reference in pack sprints at Hains Point.


YMMV, obviously.

I find your criteria of pedaling < 120 rpm @ 40 mph to be inconceivable -- but then, where I live and ride a hill is almost always less than 0.6 mi in length, and the fastest you can go before you run out of downhill and have to start climbing again is around 34 mph. I know from almost 40 years experience exactly what 96-100 gear inches means to me. The same is true for low gears. As for cadence, I had a cadence meter for a few months back in 1991, but got bored with it, and when it broke I just removed the pickup from the bike.

[CunegoFan]

You could always use rollout in meters.

It seems to me that if you wanted a single number to describe a gear then km/hour @ 100 RPM would be a good method.

Do people still use gear inches?

[RPS]

I've got an Excel program that gives me the bike speed at any given rpm, with any gear combination. Works great. Someone e-mailed it to me years ago.

Exactly. I’ve been doing the same for a long time too with one I wrote because those are the units of measure that mean most to me; and I relate to them directly every single time I ride. Bike speed, cadence, and which gear in teeth.

For instance, below is a copy of my personal spreadsheet for “evaluating” compact gearing with 11-23 cassette. Plenty of high end and low end for me most of the time, but the fact that I’d have to switch front rings every time I’d go beyond the range of 17 to 20 MPH in either direction and back would drive me nuts because I do it so often when riding rollers. That’s why I’ve ruled out compact drives thus far. I look at MPH estimates and immediately relate to what I actually experience on the roads. I know that I ride below 15 and above 25 MPH on rollers. That’s a direct observation that doesn’t require crunching numbers in my head.

P.S. -- This works for me, but the point is that with PCs everyone should be able to get what works for them more directly.

[CunegoFan]

Will anyone fess up to ever having a gear chart taped to their bike's stem? I seem to recall an old Bicycling magazine recomending such fredery.

[palincss]

Uhhh, if you live in Alexandria, then I have to differ with the assertion that doing 40 is inconceivable. I have hit 50 around here on multiple occasions.

Have done the 34 that you reference in pack sprints at Hains Point.

Depends on where "around here" is. I ride very seldom in the Catoctins or the Blue Ridge (and virtually never in Arlington), and when I do I descend rather conservatively, as my mental juke box quickly starts playing "The Wreck of Old 97," and it ain't just because the engineer's name was Steve. "Pedaling along at 40 mph" just doesn't happen in my world.

As for pack springs at Hains Point - like the Bells of Hell - go ting-aling-aling for you, but not for me... No to the packs, no to the sprints. If you do that a lot, maybe a 53x12 or 53x11 might be useful for you.

Most of my riding these days is in Southern Maryland, and what passes for hills there are generally the dips leading down to creeks, and going all out on the downhill for me it's around 34 mph and I've crossed the bridge and now the uphill begins and it's time to start down shifting.

[palincss]

I used one briefly back in 1972, for a week or two, but found it not very useful. On the other hand, my bike then was equipped with half-step + granny, and once you get the basic hang of how half-step works you don't need a gear chart. If you were tying to make Alpine work with a 5 x 2 and wanted to use every combination you were double-shifting all over the place and you really needed a scorecard to keep track of what you were doing.

[Peter B]

<snip>

Ask an average rider if he prefers a top gear of 90 inches or 110 inches and I’ll guess neither number has much meaning. Ask him up to what speed he wants to be able to pedal his bike and I’m guessing he’ll give you a MPH number right away. And if he's been riding with cadence ask him how fast he likes to spin and he'll be able to give you a quick answer as well. Inch-gear not so much IMHO.

76" please. Good for ~43mph and a hair under 200rpm. 48-17 gets me within an inch of that sweet spot.

[David Kirk]

All this will be moot soon when I introduce my new gearing system - the 1/4" pitch chain.

Right now chain link pins are 1/2" on center and therefore the teeth on the cogs are the same. So when you start getting to the smaller cogs the gearing change as a percentage gets pretty large - say when going from a 12 to an 11.

With 1/4" pitch you could have your bottom cogs be, instead of a 12 and 11, 24 and 23 teeth. This would give those small jumps we all like.

Send me money now please.

Dave

P.S. and before you tell me that it's been done before with DA10 remember that 1/4" is smaller than 10 mm so this is better.

[false_Aest]

Swimming is harder than I remember. My coach (gf) watched me swim and instantly saw that my legs were kicking as if I was riding a bike. Worked with a paddle board for the next 30 minutes.

I have muscles that I haven't used for years. YEARS!

I am slow. I will get faster.

I can rock a 6 minute mile after a month of training. A sub-60 40k shouldn't be that hard if I can convince Ben to loan me a $25K bicycle.

The weak point will be the swim. I will carry my CO2 and a tube just in case I start to drown.


Thank you for starting this thread.

[flydhest]

I was reacting to your characterization of going 40 mph as "inconceivable". I often am curious about posts people do here. For instance you say that the "fastest you can do" is around 34. It seems like you mean "the fastest I am willing to go" which is quite a different statement.

Depends on where "around here" is. I ride very seldom in the Catoctins or the Blue Ridge (and virtually never in Arlington), and when I do I descend rather conservatively, as my mental juke box quickly starts playing "The Wreck of Old 97," and it ain't just because the engineer's name was Steve. "Pedaling along at 40 mph" just doesn't happen in my world.

As for pack springs at Hains Point - like the Bells of Hell - go ting-aling-aling for you, but not for me... No to the packs, no to the sprints. If you do that a lot, maybe a 53x12 or 53x11 might be useful for you.

Most of my riding these days is in Southern Maryland, and what passes for hills there are generally the dips leading down to creeks, and going all out on the downhill for me it's around 34 mph and I've crossed the bridge and now the uphill begins and it's time to start down shifting.

[palincss]

I was reacting to your characterization of going 40 mph as "inconceivable". I often am curious about posts people do here. For instance you say that the "fastest you can do" is around 34. It seems like you mean "the fastest I am willing to go" which is quite a different statement.

I didn't say going 40 was inconceivable -- I've done 65 mph on a tandem -- but rather the notion of pedaling at < 120 rpm while doing so was inconceivable. And "fastest I can do" referred to hills like this: \/ and roughly 0.6 mi long from top to bottom, which are the norm where I ride.

It is true, I am quite unwilling to let it all go on twisty mountain descents. I won't let it go where I have no sight line, and I'm unwilling to risk the consequences.

http://lol2.homestead.com/files/old97trestle.jpg
The wreck of Old 97

However, I don't recall seeing too many people passing me on such terrain actually pedaling (and you can be sure, I've seen many, many people passing me!). It hardly seems necessary, what with gravity taking you from 20 to "no way in hell I could ever stop in time" in what feels like the blink of an eye.

[RPS]

I didn't say going 40 was inconceivable -- I've done 65 mph on a tandem -- but rather the notion of pedaling at < 120 rpm while doing so was inconceivable.
I guess inconceivable is relative. On multiple occasions I’ve reached for a taller gear while going just above 40 MPH on a downhill to close a gap on a tandem to realize I was already in my 52/11. I can spin faster but I can’t accelerate as fast at higher cadences.

My point was that we are different and we should be able to customize information as we customize our bikes to fit our particular needs. Just like your bike gearing needs are quite different than mine, some riders are not as analytical as others and may need to process information in a simpler and more direct manner.

[fiamme red]

76" please. Good for ~43mph and a hair under 200rpm. 48-17 gets me within an inch of that sweet spot.I've briefly hit 42 mph on a 49X18 fixed-gear. I think that's around 190 rpm.

[EricEstlund]

and then start humming the Breeders

I just stopped reading here- off to go find my headphones.

[RPS]

76" please. Good for ~43mph and a hair under 200rpm. 48-17 gets me within an inch of that sweet spot.I've briefly hit 42 mph on a 49X18 fixed-gear. I think that's around 190 rpm.
Don’t you guys find it interesting that you both described how fast you went at a given RPM, making “inch-gear” essentially superfluous. If most readers of this forum could relate to inch-gear as effectively as speed and cadence, a rider would simply have to say “I got to 200 RPM with a 76-inch-gear” and leave it at that since speed is already defined.

[palincss]

No, actually, Peter B described it initially in terms of gear-inches, then mentioned approximate speed and rpm required to get there with that gear, and after that, the chain ring and sprocket combination required to get that gear. Gear-inches are a handy shorthand for all that, and (as I believe is true for most fixed gear users) a reasonable way for fixed gear riders regardless of what size wheels they happen to be using to discuss it.

I doubt mph really means all that much in such cases -- after all, when you're turning close to 200 rpm on a fixed gear, how much attention span do you have left over to be consulting your computer to find out what speed you're going? In such a case, rpm is what really matters, and I think "190" could also be read as "just before my legs would have ripped off". (That's some SERIOUS rpm!)

[goonster]

I'm with Steve.

I'm aware of my gear-inches even when I have no idea of my current cadence or speed (i.e. riding fixed w/o computer).

Sheldon Brown had proposed an alternate metric, gain ratio, that included crank length in the equation. It hasn't caught on widely, and doesn't particularly appeal to me either.

The development numbers just make sense because they are constant when everything else (speed, power, cadence, effort required to pedal a particular speed at a given grade/headwind/mood, etc.) is continuously and independently variable.

[RPS]

No, actually, Peter B described it initially in terms of gear-inches, then mentioned approximate speed and rpm required to get there with that gear, and after that, the chain ring and sprocket combination required to get that gear.
...snipped.....
Palincss, you and I both know all three terms are not needed because any two define the third, right? Hence using all three is superfluous except that most people intuitively know that readers will likely need speed and cadence regardless of whether inch-gear is included or not.

My point was simply that Peter could have left it at 76 inches and 200 RPM; or 76 inches and 43 MPH. That he elected to include both 43 MPH and 200 RPM for clarity in addition to 76 inches says volumes in my opinion.

I respect your opinion and get exactly where you are coming from but can’t agree with your logic on its value. I feel certain that if personal computers had been around before the bicycle, the simplistic system of inch-gears would have never been created in the first place. It’s just like a slide rule. They still work exactly as before, but a personal computer has made their use obsolete (I find this example more pertinent than your previous one about sex). With a PC we can do so much more computation in a small fraction of the time. I like slide rules and think they were ingenious, but their time was in the past. The fact that they worked great doesn't mean we shouldn't move on.

[RPS]

Sheldon Brown had proposed an alternate metric, gain ratio, that included crank length in the equation. It hasn't caught on widely, and doesn't particularly appeal to me either.

The best thing about the Sheldon Brown system is that it is dimensionless, hence not metric or English. As long as consistent units are used for crank and rear wheel, units of measure will cancel out. It’s cool that gain ratio will work out to same value whether metric or English.

As with inch-gear, IMO it’s best suited for communication rather than evaluation.

[forrestw]

I get that in ancient times before personal computers a system of inch-gear made a lot of sense because it had to be very simple, and since guys had to do the arithmetic with pencil and paper (unless they knew how to use a slide rule) one simplistic table could be applied by everyone to their specific bike by crunching some additional bike-specific numbers. But doesn’t that seem outdated today when we can process a lot more meaningful information instantly and without effort?

Really, the computer is not gonna pedal for you or know your strengths. Far more important than the 'ancient' hand-calculated tables would be the availability of indexed shifting and 9/10 speed cassettes which give you the ability to cover a wide range while avoiding chainring shifts.

Back in freewheel days I settled on 14 16 17 18 19 24, the big jumps at top and bottom gave me range and the corncob middle provided a sweet spot for 90% of my riding. Before that I used half-step shifting.

Today I know what largest cog I need to cover 8, 10, 15, 20% grades and generally the cassette with the proper largest has no options about what the smaller cogs are like, and it doesn't matter if I think in terms of G-I, development or gear ratios, all work equally well.

Oh and for me anything less than 13 is pretty well a waste. By the time I spin out 53/13 any added speed is truly marginal.

Lastly, for about half my riding (fixed gear) who needs a computer/table/slide-rule? :-)

[Peter B]

<snip>
My point was simply that Peter could have left it at 76 inches and 200 RPM; or 76 inches and 43 MPH. That he elected to include both 43 MPH and 200 RPM for clarity in addition to 76 inches says volumes in my opinion.


I included all three merely to close the circle since the OP referenced them.

Most fixed riders I know who've done more than noodle to the coffee shop think in gear inches as representative of effort, both uphill and down, and therefore as a way to correlate that effort to gear selection for a given ride based on fitness and intent. There are multiple ways to get to a chosen gear. But once you're there that's it for the ride; no clickety-clack for variability. Speed and cadence are derivative based on fitness and terrain. A bit of forethought is prudent. For me, the computation stops as soon as the lockring is secured.

I don't focus consciously on cadence when riding with gears. I don't think about gear inches either. I intuitively select a ring or cog based on conditions of terrain, time, companions and intent, largely as perceived through effort. I guess I've discovered that a road double and 12-25 or 26 covers anything I've encountered across the body motion and effort ranges I find suit me.

I find that gear inches tells me all I need to know. There surely are other ways of relating the variables you prioritize. But if not, perhaps a spreadsheet project awaits the right individual.