[FluorescentPinkPanda]

I know Shimano makes their 10-45 for 2x but what I'd like to know is if anyone has actually tried 2x with a 10-51T cassette or similar (like a 10-50 or 10-52 Sram). I know derailleurs are rated to handle certain teeth, but I also know that exceeding the specifications usually works (for example, running a 42T Wolf Tooth back when 36T was the largest).

I've been running some calculations, and 26 to a 45 in the rear of a 29er does not offer as low of a gear as 22 to a 36 on a 26" MTB. On my 29er (29x2.7), a 26 to a 45 is exactly the same as a 24 to a 36 on a 26" wheel (26x2.125). In order to match or exceed, I need at least a 26 to 48.

I am also thinking about putting together a 22/38 on a Raceface Cinch spider instead of using Shimano's 26/36 12-speed crank, though I would be using 9 or 10-speed chainrings, which brings me to another question. Does it matter what chainrings I use up front? I'm already using a 10-speed front derailleur because no one makes a 12-speed front derailleur that will fit my bike (Specialized Taco Blade which uses a custom mid direct mount). I don't think that will be an issue because I know you can use a 9-speed chain in a 7-speed system, so it shouldn't be much different than using a 12-speed chain in a 9 or 10-speed system right?

Here's the gear calculator I used.

Sheldon Brown's Bicycle Gear Calculator

A JavaScript calculator for analyzing bicycle gearing

www.sheldonbrown.com

I understand people are going to say things like, "Just work harder, walk, there isn't much difference, why, it can't be done, etc." but I would like to know if anyone has experimented with this and what their findings were.

Also, I want a 38 for when I go faster. A 26 or 30 to a 10 is just not high enough of a gear for me.

 

[Swolie74]

Wide range MTB gearing (11-46, 11-48, 11-50 & 11-51) with 2x drivetrain for Gravel/Bikepacking/Road Bikes | Page 6 | Mountain Bike Reviews Forum (mtbr.com)

 

[Donkeeboy]

No derailleur can accommodate that much difference, even a 2 x with an 11-45 is limited.

A Pinion would work, 600% range.

 

[FluorescentPinkPanda]

Is that based on personal experience or a specific case you've seen? That transmission is neat but wouldn't that require a special frame? I probably don't need it to accommodate the full range, such as 22 to 10 because I can always upshift to the 38 when I want to go faster. I can make the chain long enough to accommodate the 38 to 51, and if the chain is too long, I can just avoid certain gears.

What I want is to be able to have a 38 up front for when I want to go faster and have a climbing gear low enough to satisfy me. I may have to just try it out to see what happens. I have a Sram 12-speed derailleur that can take a 52 and a long cage Shimano 12-speed derailleur that I can experiment with. I bought a 10-45 cassette for it but I have a 10-51 I can try first.

This guy is running something similar, and it looks like it works. 30/46 chainrings to a 11-51 cassette. The difference between 30 and 46 is the same as 22 and 38. This looks promising. I'll also be using 12-speed components, which may have more capacity.

Wide range MTB gearing (11-46, 11-48, 11-50 & 11-51)...

No derailleur can accommodate that much difference, even a 2 x with an 11-45 is limited.

A Pinion would work, 600% range.

 

[jrob300]

This guy is running something similar, and it looks like it works. 30/46 chainrings to a 11-51 cassette. The difference between 30 and 46 is the same as 22 and 38. This looks promising. I'll also be using 12-speed components, which may have more capacity.

Wide range MTB gearing (11-46, 11-48, 11-50 & 11-51)...

I do have a little experience here. I do warn people though, every one of these must be considered a one-off experiment with no guarantee that it will work. There are general principles that do apply, but chainline, chainstay length, front and rear gearing choices and FD mounting will all affect how the system works. A project like this is not for the faint of heart and you should most likely be able to do the work yourself. Most mechanics will simply throw their hands up at some point and say it can't be done.

Are you planning to use mechanical or electronic shifting?

The thing that determines overall capacity is RD design, cage length and pulley size. In general, the larger the largest rear cog is, the more offset of the top pulley you want built into the RD. That is why I went to XT Di2 RD for 11-51. I also substituted an XT8000 SGS long cage for the std. GS cage. FD capacity according to Shimano is 10t. The XT Di2 FD shifts 16t like a dream ON MY BIKE. Shimano is notoriously conservative regarding their specifications, especially capacities because they need to be able to guarantee that it will work every single time.

Mechanical shifting is a whole 'nother animal and might require an MTB RD and a Tanpan to get the capacity. Remember the road RD's are designed for smaller gears and shifting performance with the larger cogsets will suffer in the smaller cogs.

 

[bayposter]

I would be using 9 or 10-speed chainrings, which brings me to another question. Does it matter what chainrings I use up front?

The newer 12-speed Shimano drivetrains are not compatible with the older 9-, 10-, and 11-speed drivetrains. So if you want to use a 10-51T Shimano 12-speed cassette, you'll need a Shimano 12-speed chain and a Shimano 12-speed compatible chainring. But you can mix and match between all the Shimano 12-speed lines (XTR, XT, SLX, and Deore).

 

[uzurpator]

I'm going to invoke words not spoken in these parts since forever. Hide your kids, hide your wife.

How about a triple? Depending how adventurous you are - you can go towards bone stock 3x10 with 40/30/22 crank, or make an exotic 3x12 with the same crank, but 11-42 or even 10-44. That ought to give you a ton of range without trying to marry equipment that should never be mixed.

I run two bikes with 3x12 and... it just works.

 

[uzurpator]

The newer 12-speed Shimano drivetrains are not compatible with the older 9-, 10-, and 11-speed drivetrains.

I run shimano 12 speed chain on 10 speed crank ( FC-m6000 ) without issues.

 

[Le Duke]

Is that based on personal experience or a specific case you've seen? That transmission is neat but wouldn't that require a special frame? I probably don't need it to accommodate the full range, such as 22 to 10 because I can always upshift to the 38 when I want to go faster. I can make the chain long enough to accommodate the 38 to 51, and if the chain is too long, I can just avoid certain gears.

What I want is to be able to have a 38 up front for when I want to go faster and have a climbing gear low enough to satisfy me. I may have to just try it out to see what happens. I have a Sram 12-speed derailleur that can take a 52 and a long cage Shimano 12-speed derailleur that I can experiment with. I bought a 10-45 cassette for it but I have a 10-51 I can try first.

This guy is running something similar, and it looks like it works. 30/46 chainrings to a 11-51 cassette. The difference between 30 and 46 is the same as 22 and 38. This looks promising. I'll also be using 12-speed components, which may have more capacity.

Wide range MTB gearing (11-46, 11-48, 11-50 & 11-51)...

Look at how a 12s MTB rear derailleur works at each end of the gearing range, then try to add 16 teeth of chainring (and 8 complete links of chain).

With my 12s XO1 RD, in the 10 tooth, the lower pulley has gone backwards and upwards so far that the two jockey wheels are nearly level with each other. Now add 8" of chain to that. That won't work.

Also, in the link that you posted, the OP is NOT getting enough chain wrap on the cassette cogs at the high (10 or 11t) end of the range. You couldn't pay me to ride that bike.

 

[wayold]

So, is the consensus that the most range one can get reliably out of a 2x set up on a road/gravel bike using conventional road brifters is something like 30/46 GRX up front and an 11/42 cassette and GRX (or possibly even an R8000) derailleur in the back (possibly including a road link)? I'm talking something that I could just slap onto a new gravel bike and just expect to work after a bit of tweaking. I really admire all these experiments at the outer limits, but want to know how far I have to back off before it gets easy enough that a less experienced bike tuner like me can just expect it to work.

 

[jrob300]

So, is the consensus that the most range one can get reliably out of a 2x set up on a road/gravel bike using conventional road brifters is something like 30/46 GRX up front and an 11/42 cassette and GRX (or possibly even an R8000) derailleur in the back (possibly including a road link)? I'm talking something that I could just slap onto a new gravel bike and just expect to work after a bit of tweaking. I really admire all these experiments at the outer limits, but want to know how far I have to back off before it gets easy enough that a less experienced bike tuner like me can just expect it to work.

46/30 with 11-40 is fairly vanilla. I've done that on 6 bikes now (both Di2 and mechanical) and my best friend runs it on his 3T. Some require a roadlink, my current bike does not. Not a ton of data points, but I've read of enough people doing it that I would call it "reliable". If you are used to 11-28 shifting then be prepared for things to slow down a bit. Just the nature of the larger jump between cogs. I think this is probably what you are looking for.

The 11-42 will probably require a roadlink (both of our current bikes do) and maybe a little fiddling, mostly with the B-Screw, but no mods like longer/different cages, larger pulleys. I have only set up 2 bikes this way, but have read anecdotal eveidence that it works well and requires minimal modifications. Just remember, one man's "works well" is another man's "nope, nope, nope". Ref the post above yours.

After that, you are in fairly uncharted territory.

 

[FluorescentPinkPanda]

Haha, I would at least toy with that idea in my head but no one makes a mid direct mount 3x front derailleur. But then if I really wanted to get adventurous, I could fabricate something to make a high direct mount fit....hmmm. No, but my issue isn't a limited high end but a low enough low end. It shouldn't be difficult to run a 38/22 up front. I just need to figure out how big of a rear cog I can run but who knows. Maybe I won't need it. I just received my Shimano 12-speed 36/26 XT crankset today, and I can't decide if I want to use that or my Raceface Turbine with a 38/22.

The other thing is, I thought I read somewhere that Shimano HYPERGLIDE+ chains (their current 12-speed chains) aren't compatible with narrow-wide chainrings. That's the only reason I went with a Shimano rear derailleur as I like Sram rear derailleurs because of that button that can hold the cage back for much easier wheel removal. Sram rear derailleurs have a narrow-wide jockey wheel. The reason I wanted to try their HYPERGLIDE+ chain was because they advertised better and quieter performance. I wonder how the HYPERGLIDE+ chain will perform on a 10-speed Raceface crankset. Or I could just run a Sram NX Eagle 12-speed chain. That's what I use on my other bikes.

I can either have a 100% Shimano system, setup as they designed it (36/26 & 10-45), or hack something together that may or may not work (38/22 & 10-51), lol. I feel like I should try the Shimano setup first to see if the low gear is low enough for me.

Which leads me to wonder if I should just go back to 1x with a 30T up front going to a 10-51. That will get me near what a 26 to 45 would offer, and I would only lose about 4 mph of top end (at a cadence of 80) not having the 36.

Actually, I could drop down to a 28T and pair it with a 52 in the back, and that will give me the same climbing ability as a 22 to 36 on a 26" bike. My top end will only be about 5.6 mph slower without the 36T second chainring. This 1x setup will almost match the range of a 3x setup of the past!

Oh, but I can't go xD because I have a Microspline hub, though 51 vs 52 probably isn't noticeable. Hmmm, maybe I should try my 2x idea afterall with the 10-51 and 36/26. This will allow me to experience the benefits of HYPERGLIDE+.

Analysis paralysis!

I'm going to invoke words not spoken in these parts since forever. Hide your kids, hide your wife.

How about a triple? Depending how adventurous you are - you can go towards bone stock 3x10 with 40/30/22 crank, or make an exotic 3x12 with the same crank, but 11-42 or even 10-44. That ought to give you a ton of range without trying to marry equipment that should never be mixed.

I run two bikes with 3x12 and... it just works.

 

[FluorescentPinkPanda]

What are your concerns? The smaller cogs might wear at a higher rate, but they can be replaced. If it works, why not?

...in the link that you posted, the OP is NOT getting enough chain wrap on the cassette cogs at the high (10 or 11t) end of the range. You couldn't pay me to ride that bike.

 

[uzurpator]

Haha, I would at least toy with that idea in my head but no one makes a mid direct mount 3x front derailleur. But then if I really wanted to get adventurous, I could fabricate something to make a high direct mount fit....hmmm

Well, you'll need to get adventurous either way, as nobody really makes 2x FDs for mtbs which have 16T capacity. Shimano ones are 10T front difference, don't know how about SRAM. Theoretically, the same Shimmy RDs can handle up to 14T, but it is a really, really tight fit ( I know, because I tried ).

From your second post, I think that your largest limitation is the microspline driver - it severely limits cassette options. If you are hell-bent on pushing the low end, than I would consider 10-45 cassette + 32-22 crankset and proper 2x12 shimmy rear mech. This way you'd get that 22/45 low gear and 32/10 top gear - total 660% gear range. On 2.7" rubber that ought to be enough.

The upside in this setup is that your only stride away from what shimano specs would be the position of the FD, getting it low enough will require some ingenuity.

 

[FluorescentPinkPanda]

Why do you see Microspline as a limitation? I bought the wheelset because of the Microspline freehub body. I wanted to be able to have a 10 tooth in the cassette. I'm not sure why but I've never had any real interest in the xD driver. Might have been the extreme costs but at least now you can get a 10-52 for a little over $200. Shimano cassettes cost less than half that though. I also don't trust 3rd party cassettes. I've tried one, and they're definitely not as strong, and the reviews are not great.

I think what I'll try first is a Raceface 10-speed 36/24 to a 10-51 to see what happens. If it has problems with the small-small combination, I'll just try to avoid it.

It looks like this guy got his 16T span 38/22 setup to work.

22/38T Crankset?

I have a 3 ring crankset now which is 22/32/42 and running a 11-36 cassette. I really like and use the lower gears since I'm a fat old man and need all the help I can get :) I have to replace the crankset and BB so I was thinking of getting a 2 ring 24/38 and changing out the 24T for a 22T to...

www.mtbr.com

But if the 10-51 works on my bike, a 24T chainring should be low enough for me. In the chart below, I'm trying to match or get less than 3.8 mph at 80 rpm, and even 24 to 45 will achieve that (3.7), so it doesn't look like I need to do anything extreme at all. I might just change the 36 to a 38 and run a 10-45, and everything should be well within limits.

Well, you'll need to get adventurous either way, as nobody really makes 2x FDs for mtbs which have 16T capacity. Shimano ones are 10T front difference, don't know how about SRAM. Theoretically, the same Shimmy RDs can handle up to 14T, but it is a really, really tight fit ( I know, because I tried ).

From your second post, I think that your largest limitation is the microspline driver - it severely limits cassette options. If you are hell-bent on pushing the low end, than I would consider 10-45 cassette + 32-22 crankset and proper 2x12 shimmy rear mech. This way you'd get that 22/45 low gear and 32/10 top gear - total 660% gear range. On 2.7" rubber that ought to be enough.

The upside in this setup is that your only stride away from what shimano specs would be the position of the FD, getting it low enough will require some ingenuity.

 

[uzurpator]

Well, I am going to judge you for excluding 3rd party cassettes.
You are being judged.

Anyhow. It always boils down to how much jank you are willing to accept. Going off what a manufacturer specified usually entails some issues.

Microspline is a limitation because you have two cassette spreads to choose from, and each of these will dictate your RD choice and what you can do.

If you go with 10-51, then for good shifting you need 10-51 specific RD and those are completely incompatible with multiple chainrings. Large guide pulley offset is the culprit here.

If you go with 10-45, than, by Shimano's specification, you get 10T front ring spread to play with if you use dedicated RD.

if you use 10-45 RD on 10-51 cassette, not only that capacity gets reduced to extra 4T, but also your shifting is going to be somewhat compromised on the rear.

if you use 1X RD on 10-45 then the pulley offset would still exclude any front doubles.

Whence came my suggestion to use 10-45 + 2xRD and 32-22 crank + 2xFD. The only going off the manufacturer's specification would be size of the front rings, but that is pretty trivial to deal with. Otherwise, such drivetrain would be purely native.

I'm not saying that 38/22 crankset is impossible. I am saying that an FD that can shift 16T front difference is not of any of the current Shimano 2x offerings. You'd need a triple specific FD, and at that point getting a full triple makes more sense. FDs really, really like to shift what they were designed for.

had you gone with XDR driver, you'd have more wiggle room as there are also 10-30, 10-33, 10-36, 10-44, 10-50 and 10-52 cassettes, not counting 3rd party options.

If you went with HG, then what you want to achieve was trivially available with shimano XT 3x11 - 11-40 cassette and 40/30/22 crankset. Switch to 11-42 for that extra oomph would not hurt much and every part would be designed to work with every other part, no jank involved.

 

[FluorescentPinkPanda]

Haha, I am all for 3rd party but if they fail, I lose faith, which is exactly what happened when I tried one of those 11-52 cassettes off Amazon. It shifted great, until one of the middle cogs pulled out of a pin and got bent. This has never happened to any of my Shimano cassettes. I didn't have any issues with shifting though. I was putting a lot of power through it though, so I'm not totally against trying it again but now I have a Sram 11-50 on it, so unless that fails, I'm good.

If a 3rd party offered something I wanted, I'd be willing to try it, like maybe an even larger rear cog. Way back before Wolftooth came onto the scene with the 42T, I had a 41T by MTB Tools. This was back when 36 was the largest, so having a 41 on a 26" bike was crazy. Then when Wolftooth came out with the 42, I jumped on it and loved it, and then the 50T Oneup, which came with a really long cage to replace the stock cage on the Shimano derailleur. This stuff all worked great.

I guess my issue is with 3rd parties that use junk materials. I was curious about those 9-52T cassettes but the reviews don't look good.

The bike I'm working on now is my main all-purpose trail bike, so I don't want anything too weird going on. That's why I have all Shimano 12-speed components on it (except for the shifter because I like the way the Sram shifter feels more than the Shimano XT, the XT's action is not light enough). I wanted to see if any of Shimano's claims about Hyperglide + were true, which leads me to another problem.

I don't know if the Shimano chain I bought from a seller on Amazon is genuine. Who can I buy from that guarantee's authenticity? In the world of cameras, if I buy from B&H, I know I'm buying the real thing. Is there an equivalent in the cycling industry?

Does anyone make a mountain bike wheel with an XDR driver? And why would someone want any of those other cassettes on their mountain bike anyway? It's interesting that Shimano's 11-46 was for 1x while their new 10-45 is for 2x. Maybe their next 13-speed system will have a 10-50 2x.

But unfortunately for me, I don't think any 3rd parties are going to make a larger cog because there isn't as much of a need or demand. People seem happy with their 1x drivetrains, or so I assume. My biking buddies are still on 42s from the last decade. I guess I just need to exercise more.

One of the 11-speed mid direct mount Sram front derailleurs for my bike has 12T stamped into the cage, so I assume that means it handles 12T. I have all that parts I need for my experiments, so I'll just go try it out. The Raceface Cinch 2x spider came with 24/36 chainrings. I have a 38 I can pop in to try. If this works with the 10-51 out back, I will be very happy. In reality, I'd probably be perfectly fine with 24 to 45. Also, 24 is actually very close to what I would put in my 1x setup. I had a 26T Wolftooth chainring in front until I decided later that 28 would probably be better for more top end. If the Shimano 26/36 wasn't brand new, I'd try it first because I want to be able to return it if the Raceface setup works. The main reason I like the Shimano I bought was because I got it with 165mm crank arms, and I read that shorter crank arms might be better for your knees. I'm 5'9", and various crank calculators suggest shorter cranks than the 175mm I chose for my Raceface Turbine crankset.

There I go with my analysis paralysis again.

Well, I am going to judge you for excluding 3rd party cassettes.
You are being judged.

Anyhow. It always boils down to how much jank you are willing to accept. Going off what a manufacturer specified usually entails some issues.

Microspline is a limitation because you have two cassette spreads to choose from, and each of these will dictate your RD choice and what you can do.

If you go with 10-51, then for good shifting you need 10-51 specific RD and those are completely incompatible with multiple chainrings. Large guide pulley offset is the culprit here.

If you go with 10-45, than, by Shimano's specification, you get 10T front ring spread to play with if you use dedicated RD.

if you use 10-45 RD on 10-51 cassette, not only that capacity gets reduced to extra 4T, but also your shifting is going to be somewhat compromised on the rear.

if you use 1X RD on 10-45 then the pulley offset would still exclude any front doubles.

Whence came my suggestion to use 10-45 + 2xRD and 32-22 crank + 2xFD. The only going off the manufacturer's specification would be size of the front rings, but that is pretty trivial to deal with. Otherwise, such drivetrain would be purely native.

I'm not saying that 38/22 crankset is impossible. I am saying that an FD that can shift 16T front difference is not of any of the current Shimano 2x offerings. You'd need a triple specific FD, and at that point getting a full triple makes more sense. FDs really, really like to shift what they were designed for.

had you gone with XDR driver, you'd have more wiggle room as there are also 10-30, 10-33, 10-36, 10-44, 10-50 and 10-52 cassettes, not counting 3rd party options.

If you went with HG, then what you want to achieve was trivially available with shimano XT 3x11 - 11-40 cassette and 40/30/22 crankset. Switch to 11-42 for that extra oomph would not hurt much and every part would be designed to work with every other part, no jank involved.

 

[J_Westy]

I'm not saying that 38/22 crankset is impossible. I am saying that an FD that can shift 16T front difference is not of any of the current Shimano 2x offerings.

Came across this build from velo orange... maybe interesting with it's 46/30 chainrings x 11-34 cassette.

 

[speedygz]

This is what works for me. Brilliantly. And has for a year or more. All on a non boost frame & 135mm spacing wheels. XT 11 speed shifter. m7000 SLX rear derailleur, & 11-46 cassette. Any non boost 2x crank, I'm running 36/24 steel chainrings (Shimano recommend only 10t difference, 12 works fine), and that's the max difference you can run. Chain has to be accurately sized to suit. And an XT side swing 2x11 front derailleur. On 36:11 (top gear) you get a 3.273 ratio. At 24:46 (low gear) you get 0.522 ratio. That's low enough to climb a cliff, even if you're old & weak. It works. As I said, brilliantly. Smooth, slick, noise free, & reliable. Bang for buck, I can't see how you'd do too much better.

Edit. Don't bother with that microspline garbage. A 10t sprocket is ridiculous. Absolutely ridiculous. 11t is bad enough, the inefficiency of 10t is crazy.

 

[FluorescentPinkPanda]

I'm back with an update, and I'm ecstatic to report that it all works! This makes me so happy!

The 10-51 tooth cassette works in a 2x setup!
The 22 tooth chainring works on the crankset in place of the 24 or 26.
The 38 tooth chainring works on the crankset in place of the 36.
Most importantly, the 38/22 combination works!
A 12-speed chain works on a 9 or 10-speed chainring.
A 12-speed chain works with 10-speed chainring spacing for 2x shifting.

I was about to try this 20 tooth chainring in the crankset but now that the 51 works, I won't need it.

https://amtber.com/ols/products/20t-chainring

I did try the 10-45 tooth cassette with a 22/36, and I found that the 22 to 45 combination was good but I wanted more 😄.

The 38 to 10 provides me with the same high gear as a 40 to 11, so it basically covers the same range as a 22/30/40 triple would on a bike with a cassette that has an 11 tooth cog.

I really like Shimano's Microspline system. I've considered a Sram cassette but they cost twice as much. I am using a Sram 12-speed shifter though because I like the way it feels vs. the Shimano XT 12-speed shifter I have on another bike. The main advantage of the XT shifter is that it can upshift two gears per pull while the Sram only changes one gear at a time. I can only imagine this would be an issue if I was racing. I hear people prefer the feel of Shimano's lower end shifters vs their XT shifter (12-speed). But the main reason I bring this up is so that people know Shimano and Sram 12-speed components are interchangeable (they have the same pull ratio).

Anyway, I'm proud to run this 2x setup while almost everyone else has seemingly switched over to 1x.

Here's a picture of the large-large combination. I would never use this but it's good to know it won't break anything if I accidentally shift into it.

Here's the small-small combination to show that the RD-M8120 derailleur has enough capacity to pick up the slack so that the chain at the bottom doesn't come into contact with itself on the upper jockey wheel. Right now, the chain does not touch the front derailleur cage, but if I were to try the 20T chainring, it would probably touch in this combination, but I would never actually use the small-small combination, so this would be ok.