Gear ratio research
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Gear ratio research
Hey guys. I just did some calculations about the gear ratios on my bike and though it might perhaps be useful for someone if I shared it.
I have a 29er with a cheap Shimano Alivio level 44/32/22 crankset and HG30 11-32 9spd cassette. After a few months of commuting with it in the very flat region of Flanders, I noticed that I am always on the middle ring and have only ever used the smallest 7 sprockets in the back. So I made a little spreadsheet of the ratios my current setup gives, and started looking at other setups that I might upgrade to (for the hell of it, I don't really have complaints about the Alivio crank. You can see the results in the image below. Green gears are gears I use often, yellow gears are gears I only need in extreme circumstances (headwind+up a bridge or tailwind+off a bridge). Grey gears might as well not be there as far as my use pattern is concerned.
As you can see, a 2x10 setup would give me all my useful gears on the big ring, with a bunch of lower ratios on the small ring that I'll probably never use. 2x9 would also work with my current cassette. But since the small ring is obsolete, even that is a lot of unnecessary scrap metal on the bike for me.
Then I started to look at the Zee crank. From what I see the Zee group is about the same level as SLX, but looks much nicer if you ask me. The 36T Zee crankset would give me all the ratios I ever used right in the middle of my original cassette (good for the budget), with one spare ratio on either end. I'll probably end up going this way, I calculated that throwing out the current crank, the front derailer and one shifter will net me about 700 grams weight loss, which is pretty cool for 90 euros.
Finally I looked to get a closer range road cassette. Having a 9spd (XT) derailer, the Sora/Tiagra 12-25 cassette is the one to go for, and this would spread out my commonly used ratios over 7 instead of 5 sprockets (the 23T one is near-as-dammit green). This may seem unnecessary to you folks with highly varied terrain, but on my 10 mile commute there are a lot of subtle changes in gradient and I find myself shifting back and forth sometimes looking for the ideal cadence.
Short summary: flat roads? Get single ring crank.
Spreadsheet can be obtained from https://telin.ugent.be/~dvhamme/bikeratios.ods but it's open document format, so excel won't read it (openoffice/staroffice/libreoffice will).
I have a 29er with a cheap Shimano Alivio level 44/32/22 crankset and HG30 11-32 9spd cassette. After a few months of commuting with it in the very flat region of Flanders, I noticed that I am always on the middle ring and have only ever used the smallest 7 sprockets in the back. So I made a little spreadsheet of the ratios my current setup gives, and started looking at other setups that I might upgrade to (for the hell of it, I don't really have complaints about the Alivio crank. You can see the results in the image below. Green gears are gears I use often, yellow gears are gears I only need in extreme circumstances (headwind+up a bridge or tailwind+off a bridge). Grey gears might as well not be there as far as my use pattern is concerned.
As you can see, a 2x10 setup would give me all my useful gears on the big ring, with a bunch of lower ratios on the small ring that I'll probably never use. 2x9 would also work with my current cassette. But since the small ring is obsolete, even that is a lot of unnecessary scrap metal on the bike for me.
Then I started to look at the Zee crank. From what I see the Zee group is about the same level as SLX, but looks much nicer if you ask me. The 36T Zee crankset would give me all the ratios I ever used right in the middle of my original cassette (good for the budget), with one spare ratio on either end. I'll probably end up going this way, I calculated that throwing out the current crank, the front derailer and one shifter will net me about 700 grams weight loss, which is pretty cool for 90 euros.
Finally I looked to get a closer range road cassette. Having a 9spd (XT) derailer, the Sora/Tiagra 12-25 cassette is the one to go for, and this would spread out my commonly used ratios over 7 instead of 5 sprockets (the 23T one is near-as-dammit green). This may seem unnecessary to you folks with highly varied terrain, but on my 10 mile commute there are a lot of subtle changes in gradient and I find myself shifting back and forth sometimes looking for the ideal cadence.
Short summary: flat roads? Get single ring crank.
Spreadsheet can be obtained from https://telin.ugent.be/~dvhamme/bikeratios.ods but it's open document format, so excel won't read it (openoffice/staroffice/libreoffice will).
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You have a very unique use case, especially in the mountainbiking forum. So, yes, I agree that you only need one chainring and furthermore I agree that you could probably ride a fixed gear or singlespeed and do just fine.
But I disagree that your findings are very useful to others.
But I disagree that your findings are very useful to others.
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Hah, I should have known the ss/fixie folk would jump on that I have a fixed gear steel road bike but it's not that interesting for a commute; the variability on my travel time is much larger with the fixie and that's annoying when there's a train to catch.
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You have a very unique use case, especially in the mountainbiking forum. So, yes, I agree that you only need one chainring and furthermore I agree that you could probably ride a fixed gear or singlespeed and do just fine.
But I disagree that your findings are very useful to others.
But I disagree that your findings are very useful to others.
Also, I found it interesting nonetheless, whatever your use case it raises some questions. Why would any new bike come with a 3x9 setup? Half a gear is the only reward for the extra chunk of metal over a 2x10. Also, do you use the lowest 3 gears on your 2x10 setup? Those three are about all you lose compared to a 1x10. I'm thinking many trail riders are carrying a significant portion of drivetrain they could do perfectly without. And I wish there had been a non-downhill 1x10 bike for sale when I was shopping, cause now I'll end up with a crate full of spare parts.
Surely my use case is not that uncommon, even if it's closer to mild XC than all mountain
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Also, I found it interesting nonetheless, whatever your use case it raises some questions. Why would any new bike come with a 3x9 setup? Half a gear is the only reward for the extra chunk of metal over a 2x10. Also, do you use the lowest 3 gears on your 2x10 setup? Those three are about all you lose compared to a 1x10. I'm thinking many trail riders are carrying a significant portion of drivetrain they could do perfectly without. And I wish there had been a non-downhill 1x10 bike for sale when I was shopping, cause now I'll end up with a crate full of spare parts.
Surely my use case is not that uncommon, even if it's closer to mild XC than all mountain
Surely my use case is not that uncommon, even if it's closer to mild XC than all mountain
2. in Kansas, no, I don't use the three lowest gears on my 2x10. in colorado, yes, I would. I'm going there in July.
3. no, you are wrong. a 1x10 loses a LOT compared to even my fairly close range 2x10. (I have 28/39 chainrings with 11-36 cassette.) I can spin out the 39x11 on flat ground in a burst, or easily downhill. imagine that with a typical 32 or 34T single ring. (you are in the MTB forum, remember.) and I while I can ride most trails without leaving my big ring, if I need the granny ring it is a significant help, being 11 teeth less than my big ring. in this case, a 32T single ring probably would be adequate for climbing though, since 32x36 is a lot of gear. but I'd give up a bunch of top-end speed.
your use case is really weird because you have no hills and you're commuting. why you are doing that on a 29er is beyond me...
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I have some comments:
- Zee is made for downhill as far as I know.
- Instead of using excel, you can use this website for your calculation: https://gear-calculator.com/
- I agree with ColinL, yours is a unique case in MTB.
- Zee is made for downhill as far as I know.
- Instead of using excel, you can use this website for your calculation: https://gear-calculator.com/
- I agree with ColinL, yours is a unique case in MTB.
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my sram x9 2x10 weighs 782 grams with the chainrings and standard gxp bottom bracket. I weighed it on a park tool scale last month after re-greasing the bearings, but I didn't take a pic.
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3. no, you are wrong. a 1x10 loses a LOT compared to even my fairly close range 2x10. (I have 28/39 chainrings with 11-36 cassette.) I can spin out the 39x11 on flat ground in a burst, or easily downhill. imagine that with a typical 32 or 34T single ring. (you are in the MTB forum, remember.) and I while I can ride most trails without leaving my big ring, if I need the granny ring it is a significant help, being 11 teeth less than my big ring. in this case, a 32T single ring probably would be adequate for climbing though, since 32x36 is a lot of gear. but I'd give up a bunch of top-end speed.
I wanted to build up my own bike just for the purpose of getting the most speed out of my commute with the least effort, but any build ended up costing hundreds more than a fully specced bike with similar grade components So now I'm stripping my perfectly fine MTB because I only need two thirds of an actual MTB. Make some sense?
That's pretty nice. Can you recommend me any single ring cranksets (any brand) since you seem to know a lot about it?
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Middleburn RS8 Uno comes to mind.
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I looked at both the RS8 and the RS7 but they're both rather more expensive than the Zee. It seems the Zee is quite a steal at the moment for 89 euros at bike-components.de (that's with the 68/73 BB).
There's nothing really wrong with the alivio crank though, perhaps I should just throw a 36T singlespeed ring on it and be done.
There's nothing really wrong with the alivio crank though, perhaps I should just throw a 36T singlespeed ring on it and be done.
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this is a completely stupid ass thread in the MTB forum. put it in the commuting forum if thats all you do on your mtb. anybody who does any reasonable level of MTB probably uses more than 7 gears or wishes they had more than 7 gears from time to time. I do agree, triples are probably largely unnecessary for a lot of people and even doubles, but most people that ride a 1x8 setup find they wish they had some better spacing or better range. 1x10 is nice because it lets you get that 36 cog in the mix. SRAM XX1 even better, gets you a 10 cog and a 42 cog
you really want stiff and lightweight put a road double on and only use the inner ring and put a bash on the outer.
you really want stiff and lightweight put a road double on and only use the inner ring and put a bash on the outer.
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this is a completely stupid ass thread in the MTB forum. put it in the commuting forum if thats all you do on your mtb. anybody who does any reasonable level of MTB probably uses more than 7 gears or wishes they had more than 7 gears from time to time. I do agree, triples are probably largely unnecessary for a lot of people and even doubles, but most people that ride a 1x8 setup find they wish they had some better spacing or better range. 1x10 is nice because it lets you get that 36 cog in the mix. SRAM XX1 even better, gets you a 10 cog and a 42 cog
you really want stiff and lightweight put a road double on and only use the inner ring and put a bash on the outer.
you really want stiff and lightweight put a road double on and only use the inner ring and put a bash on the outer.
Friendly guy aren't you. I checked out road cranks as per your suggestion but from what I can see it doesn't really end up being cheaper for the same weight or lighter for the same price than the Zee crank. Thanks for your opinion anyway.
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Get used to it; that seems to be what 75% of the threads on the MTB forum are any more .
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If on a 10 mile relatively flat commute you can't regularly use a 44T chainring - you don't need a new crank. You need a a new cardiovascular system. Those cute little graphs just underline that problem.
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Nice attitude though, did it come with the bike?
Everyday I see a dozen guys on mountain bikes on paved roads. None of them have mud on their face. Perhaps they're missing the point, just like I am. Or maybe they like to ride a mountain bike, like I do. Maybe they like the feel of the bike; the compromise between comfortable posture, good visibility and reasonable speed. Maybe like me they've concluded that they don't use the drop bars on their road bike often, and got tired of being beat up by the rock hard tires. Then maybe they discovered that on their slick-shod mountain bike they're no slower than on their road bike, and it feels better.
I've looked at city bikes. None of them are really nice, probably because they assume you'll use them twice a week to do 2 miles each time. I've looked at trekking bikes. They're ludicrously heavy, maybe because they assume you'll put on 100lbs of panniers and the frame needs to be made of girders. There is no better bike for my ride than the one I have. Which is a mountain bike. So I posted some on the face of it totally inoffensive, objective information about gear overlap in the mountain bike forum, thinking it is probably frequented by more than a hard core of boulder jumping, mud tearing, forest climbing athletes. Sadly some of those very guys seem to hate me for the mere fact that I ride a mountain bike on something other than a mountain.
If you don't like the way I use my mountain bike, tough luck. Because I do.
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Sometimes I'll go for a cruise on my road bike and only average ~12mph, and I generally stay on the small ring when I do. Obviously 12mph is nothing for a nice road bike, and I can easily average much higher than that, but different circumstance and goal of the ride call for different gear usage. I wouldn't want to muscle my way to work at high speed and get there sweaty and tired either.
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This subforum could and should be renamed "Offroad Cycling" since it seems that many folks mistake "Mountain Biking" for "Riding a Mountain Bike on Roads."
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Totally depends what pace you're keeping. Riding around at a slower cruising pace in the largest chain-ring and smallest rear cog is completely inefficient, just like trying to maintain high speed in the opposite gears.
Sometimes I'll go for a cruise on my road bike and only average ~12mph, and I generally stay on the small ring when I do. Obviously 12mph is nothing for a nice road bike, and I can easily average much higher than that, but different circumstance and goal of the ride call for different gear usage. I wouldn't want to muscle my way to work at high speed and get there sweaty and tired either.
Sometimes I'll go for a cruise on my road bike and only average ~12mph, and I generally stay on the small ring when I do. Obviously 12mph is nothing for a nice road bike, and I can easily average much higher than that, but different circumstance and goal of the ride call for different gear usage. I wouldn't want to muscle my way to work at high speed and get there sweaty and tired either.
But 44 is already a big step down from 48T .... or 46T .... and not even close to the 50T or 52T thats standard on most road bikes.
Thing is - I run a 44/32/22 on a mtb myself to commute about the same distance and am also not big on arriving sweaty. I'm 60 and just passed my physical this morning with no heart or blood pressure issues. Still think your gearing isn't the problem but change it if you want to.
Last edited by Burton; 02-12-13 at 03:12 PM.
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I run a 1x8 drive train for one of my winter commuters. Are you using road slicks for your bike?
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Without commenting on the rest of this thread, I think that's a good idea.
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I am about to move this thread to the Commuting forum. Will give it a while longer.
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You seem to think that anyone that doesn't absolutely love your little compilation has an attitude problem.
But 44 is already a big step down from 48T .... or 46T .... and not even close to the 50T or 52T thats standard on most road bikes.
Thing is - I run a 44/32/22 on a mtb myself to commute about the same distance and am also not big on arriving sweaty. I'm 60 and just passed my physical this morning with no heart or blood pressure issues. Still think your gearing isn't the problem but change it if you want to.
But 44 is already a big step down from 48T .... or 46T .... and not even close to the 50T or 52T thats standard on most road bikes.
Thing is - I run a 44/32/22 on a mtb myself to commute about the same distance and am also not big on arriving sweaty. I'm 60 and just passed my physical this morning with no heart or blood pressure issues. Still think your gearing isn't the problem but change it if you want to.
Also, I don't think you have an attitude problem because you don't like my spreadsheet. I think you have an attitude problem because you assume my cardiovascular system sucks since I don't use the big ring on my bike. You are basically saying that everyone who commutes slower than 40km/h is not fit. If you are going to stand by that opinion, then I'm sorry your mind hasn't aged as well as your heart has.
Do what you see fit; I thought I might get some interesting feedback by posting it here. Instead I seem to have become the personification of some resident frustration with people riding mountain bikes on things other than mountains.
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I don't have a problem, everything works. I can ride on the big ring if I want to, but there's no point because I can do up to 40km/h on the middle ring without spinning out. Note that I have a 29er with huge tires, I don't know what kind of mtb you run but you may not be able to do those speeds without using the three gears on the big ring that don't overlap with the middle one.
Also, I don't think you have an attitude problem because you don't like my spreadsheet. I think you have an attitude problem because you assume my cardiovascular system sucks since I don't use the big ring on my bike. You are basically saying that everyone who commutes slower than 40km/h is not fit. If you are going to stand by that opinion, then I'm sorry your mind hasn't aged as well as your heart has.
Also, I don't think you have an attitude problem because you don't like my spreadsheet. I think you have an attitude problem because you assume my cardiovascular system sucks since I don't use the big ring on my bike. You are basically saying that everyone who commutes slower than 40km/h is not fit. If you are going to stand by that opinion, then I'm sorry your mind hasn't aged as well as your heart has.
The 44/32/22 combination is on a mtb with 26x2.5in tires
On the mtb with 700x50 Marathon Supremes I run a 53/39/30
I use them both regularly for commuting and mostly use the large chainrings.
The wife's stock configuration was just recently dropped from 48/36/26 to 44/32/22 on 700x40 tires. She's fifty-six years old and one hundred fifteen pounds.
Read whatever you want to out of that. Personally I think this thread should have been posted in the commuting section anyway.
Last edited by Burton; 02-13-13 at 07:39 AM.