SRAM 12s Chainline Tolerance vs L/R Varience Possibilities- Mtbr.com
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  1. #1
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    SRAM 12s Chainline Tolerance vs L/R Varience Possibilities

    I have this crazy idea about testing the 12s SRAM with a RF Aeffect 3x spider upfront with 3 different chainrings of different sizes. Extra crazy part... Not necessarily to actively shift between the chainrings, but, instead, to have the option of manually moving the chain to one ring or the other based on the ride conditions I might be facing. This might be very useful if attacking some very steep hills or when needing a high gear if in ebike mode.

    So, the idea here is to have 3 "ready to go" chainrings that the chain could be switched to (by hand before riding) based on ride conditions or for testing purposes, but not necessarily to shift between the rings while riding with a FD.

    Soooo, that's my issue really. Just how tolerant is the chainline [CL] going to be with working ok, when using three chainrings that are not going to be perfectly centered for the design spec CL of 66.5mm for the DUB 12s Fat 170mm???

    Will the outer3/inner1 c-rings still work ok with 12s shifting of the RD???

    What do you think? Anyone?
    Last edited by deVries; 12-17-2018 at 08:57 PM.

  2. #2
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    Other than the chainline you would also face the issue of chain length. Different size front rings require a longer or shorter chain.

    If the chain is not long enough you can rip off your RD, and if the chain is too long it would be too slack. It might work in some gears, but no derailleur has enough capacity for an 11-50 and a triple.

    Another problem, these SRAM rear derailleurs are 1x specific, they use an offset pulley. If you adjust the B-gap on one chainring, and then you put the chain on a different size chainring, your B adjustment is gonna be all screwed up, and Eagle is very sensitive to this.

    IMO don't do it. If you really require that much gear range, get a stock triple setup like an XT 3x11.

  3. #3
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    ^^^ yes. The chain line isn't the issue. As many have found out, proper chain length and B gap is critical. Changing the ring by more than a few teeth will require adjusting the chain length and B gap.

    Rear derailleurs have a specification called tooth capacity, or chain wrap capacity. It's the total difference in teeth of the cassette plus the total difference in teeth of the chain rings. The main aspect of the derailleur that limits this is the length of the cage. The Eagle RD is designed around a tooth capacity of 40 (50-10). If you have two rings differing by 10 teeth in addition to the 10-50 cassette, you'd need a RD with a capacity of 50 teeth.
    What, me worry?

  4. #4
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    Quote Originally Posted by Lone Rager View Post
    ^^^ yes. The chain line isn't the issue. As many have found out, proper chain length and B gap is critical. Changing the ring by more than a few teeth will require adjusting the chain length and B gap.

    Rear derailleurs have a specification called tooth capacity, or chain wrap capacity. It's the total difference in teeth of the cassette plus the total difference in teeth of the chain rings. The main aspect of the derailleur that limits this is the length of the cage. The Eagle RD is designed around a tooth capacity of 40 (50-10). If you have two rings differing by 10 teeth in addition to the 10-50 cassette, you'd need a RD with a capacity of 50 teeth.
    I have read about people using other branded cassettes with the SRAM 12s 1x front and 12s chain. Could I use a different cassette to change the cog tooth count to under 50? I would want to use a 34/36t CR paired with a 44t CR, so can I get a cassette that allows me to use a lower cog tooth count in those low gears? Like go from the 50t cog to a 40 or 42t cog and still use the SRAM RD and 12s chain???

    I'm not sure WHY I would want to do that? LOL. I'm just thinking crazy ideas right now without a very good logical foundation for doing this. Crazy?

    AND, IF that is even possible, would I still be screwed with the chainline issue? One thing, my chainstay is very long at 20" inches, so this might help somehow too? Not so angular a chainline???

  5. #5
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    To tweak this idea further and isolate the problem to be only with the chainline, not also with chain slop or tightness, then couldn't I limit the RD from using the 50t or 11t cog (as needed) when using an outer3CR or inner1CR position. I could even take this idea further by not adjusting the RD and just not even shift into certain near L/R end-cog highest/lowest gear positions, when also using the outer3CR or inner1CR position.

    IF I was mindful and cautious enough, then I could just NOT shift into the extreme cogs to tension or slop the chain enough to cause any problems. Or, as noted above just limit the RD from shifting to the extreme cog positions anyway. Isn't this just a screw adjustment? I could just memorize how many screw turns for each chainring size/position CR1, CR2, or CR3 I'm going to use.

    Thus, only the L/R chainline specification would be the issue if able to do the above too.

    Also, by avoiding to shift to extreme cog positions when using CR3 or CR1, then the chainline is not sooo extreme with chain "angle twist" [staying more on side of alignment w/rear cogs to front outer/inner CR's], also, with a chainstay that is about 20-1/2 inches long anyways. Thus, moderating angular twist further.

    Right? or ??? Still crazy?

  6. #6
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    Again all I can say is please look up how a SRAM 1x X-horizon rear derailleur works compared to a regular one. Or if you have a bike with a SRAM 1x rear derailleur and another bike with any other normal derailleur just swing the cage forward on both and look how the upper pulley moves.

    Doesn't matter if you avoid the extreme cogs, it's not going to work. And yes, the idea is still crazy and pointless. I probably sound like an azz but I just don't understand why you would want to do something like this. Especially after we explained it's not going to work.
    Even if it would work if you avoided the extreme cogs(it still won't), you're limiting the cogs that you could use on your rear cassette, then you move the chain by hand from one chainring to another? What's the point? Why not just get a double or a drivetrain that does what you want?

  7. #7
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    Quote Originally Posted by HollyBoni View Post
    Again all I can say is please look up how a SRAM 1x X-horizon rear derailleur works compared to a regular one. Or if you have a bike with a SRAM 1x rear derailleur and another bike with any other normal derailleur just swing the cage forward on both and look how the upper pulley moves.
    I've bought the SRAM 12s NX w/DUO, but it won't be here until late January. So, I will get some first hand experience using this setup as is intended.
    Quote Originally Posted by HollyBoni View Post
    Doesn't matter if you avoid the extreme cogs, it's not going to work. And yes, the idea is still crazy and pointless. I probably sound like an azz but I just don't understand why you would want to do something like this. Especially after we explained it's not going to work.
    Sometimes I learn more by banging my head against a futile problem, which then leads to a unique and "outside the box" solution. I'm sort of a Bat Sheeit Crazy guy that will work a problem with no solution only to think of another way to solve it. So, humor me, as I might do something weird and yet solve this non-solution by other means.
    Quote Originally Posted by HollyBoni View Post
    Even if it would work if you avoided the extreme cogs(it still won't), you're limiting the cogs that you could use on your rear cassette, then you move the chain by hand from one chainring to another? What's the point? Why not just get a double or a drivetrain that does what you want?
    Well, I could use two different length chains too, if necessary. It's not that time consuming to switch chains for an outing, and I don't need to switch chainring gears once I'm on "the ride". I have two very different purposes with different gearing specific to having normal gearing like a 34/36t or higher gearing of at least a 44/46t. Plus, I don't have to use the alternate CR very often, so I won't need to swap between the two except occasionally.

    Yes, I already understand I'm probably going to have to avoid chainline issues too if using two chainrings, but there might be ways to solve chainline problems too. One Up and Wolf Tooth allows for quick change-out of CR's, but don't know if this can work with DUB, so I may find a similar solution or use their solution or an related idea. I'm working on it. And, I'm "too hassled" to want to switch out DM CR's on the DUO. It's got to be easier and faster than that.

    My fall-back position is to go with a 2x CR drive up front paired with an 10/11 cog system designed to work w/2x 104 or 110bcd CR, but I'm hoping to somehow get this 12s to do what I need. This is NOT for a normal application that needs a FD and needing to change between 2x CR's during a ride. There will be two different applications of cycling that allows for this, but it won't work if I have to switch out the 12s/RD and 12s/shift mechanisms every time.

    Let's see what happens...

  8. #8
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    If you used 12 chainrings and 12 different chains you could maintain perfect chainline.
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    If you're willing to use two different chains then just get two 1x chainrings. Even with direct mount it's pretty easy to change them on SRAM cranks.

    But then you will run into small issues again, like rotating two chains on the same cassette and chainring, and re-using quick links multiple times.

    I have no issues at all with "out of the box solutions" but this idea is just dumb, sorry. To me it feels like you simply bought the wrong groupset for your application, or you think you need that much range but in reality you don't. Yeah you "only" have the 11-50, but for example a 10-50 provides a pretty darn massive gear range. As much or sometimes even more than some 2x11 systems.

    Now i'm just asking because of my own curiosity, with a 520mm chainstay length what kind of bike is it, and why does it need a 46T chainring?

  10. #10
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    Quote Originally Posted by HollyBoni View Post
    If you're willing to use two different chains then just get two 1x chainrings. Even with direct mount it's pretty easy to change them on SRAM cranks.

    But then you will run into small issues again, like rotating two chains on the same cassette and chainring, and re-using quick links multiple times.

    I have no issues at all with "out of the box solutions" but this idea is just dumb, sorry.
    I was hoping to use a reusable [connex] quick connector like this:

    https://www.connexchain.com/en/product/connex-link.html

    If there's no way to easily change-out the chain quickly, like connex, then using two different chains is not possible. I'll just not be able to shift into the 50t, or more precisely a 8-10t difference, when using the bigger CR. I won't need it anyway for that application, but then there is the question of RD and/or shifter adjustment and how easy vs difficult that will be to do quickly. If it can't be done fast and easy, then my idea is probably at a dead end.
    Quote Originally Posted by HollyBoni View Post
    Now i'm just asking because of my own curiosity, with a 520mm chainstay length what kind of bike is it, and why does it need a 46T chainring?
    I may be using 24" wheels for one configuration, so I'll need the bigger CR in order not to spin-out at too high an rpm for pedaling.

  11. #11
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    Quote Originally Posted by HollyBoni View Post
    To me it feels like you simply bought the wrong groupset for your application, or you think you need that much range but in reality you don't. Yeah you "only" have the 11-50, but for example a 10-50 provides a pretty darn massive gear range. As much or sometimes even more than some 2x11 systems.
    I think I can get this to work, and, luckily, I don't need the entire low range. By blocking the use of the 50t ring it will leave the 42t as my low gear. That will be plenty of low range for my needs when paired with a 34t CR, and this should allow for a 44t CR to either be swapped out for the 34t or work in a paired 2x side-by-side configuration. I'll just manually move the chain over to the selected CR by hand as needed. I won't need to change the chains, because this won't exceed the capacity of the RD or create too much chain slop.

    Also, by blocking the 50t from being accessed in either the 34t/44t CR should allow for the RD to function without having to change the settings??? Or, at least easily make any adjustment quickly.

    Am I mistaken?

  12. #12
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    Quote Originally Posted by deVries View Post
    Am I mistaken?
    Yes. Once again, please look up how a SRAM 1x rear derailleur works.

    Doesn't matter if you don't use the entire cassette, you can't jump from a 34T to a 44T chainring and maintain the proper B-gap with the same chain even if you mess with the B screw because the B-gap is tied together with the chain length.



    Eagle is super sensitive to the B-gap in stock form, and you're expecting it to work after a 10 tooth chainring jump. Just to give you an idea, on a full suspension you have to set up the B-gap under sag.

    If you are dead set on getting this groupest you're going to try what you want anyways. It's pointless to say anything really. You don't fully understand how things work but you don't believe what we say.

    Good luck!

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    Quote Originally Posted by HollyBoni View Post
    Eagle is super sensitive to the B-gap in stock form, and you're expecting it to work after a 10 tooth chainring jump. Just to give you an idea, on a full suspension you have to set up the B-gap under sag.

    If you are dead set on getting this groupest you're going to try what you want anyways. It's pointless to say anything really. You don't fully understand how things work but you don't believe what we say.

    Good luck!
    Yes, I agree, I don't fully understand. I saw a YT video that shows the B adjustment here:

    https://www.youtube.com/watch?v=YjgBtCObYDY

    What I'm wondering is why can't I just notate the B adjustment "measurements" that are different between the two CR's to get each one to work separately, and, then, just do "monkey see monkey do" to get back to those same settings and adjustments by mimicking and repeating exactly what I did initially to get each CR separately to work???

    Once I know the initial two different settings, then why can't I just readjust the B setting and gap differences between the two CR's that are correct to use for each unique CR?

    Btw, I do appreciate your help, and I'm not being argumentative or hard headed here. I'm perfectly happy if this won't work-out.

    But it seems obvious to me if the chain length "wrap" issue can be balanced-out by not using the 50t cog and using the same identical chain [same length], gaining maybe 10t for a larger CR, then I'll just need to change the B "gap" adjustments.

    Yes, I will have to change the RD B "gap" adjustments and the inner large cog L/R shift limiter preventing the 50t cog use, but once I know these "B gap" settings, then why can't I just reuse those same working positions and change these settings accordingly for each CR size each time I swap CR's? Is that soooo difficult to do? It can't be repeated over and over when using the same two different sized CR's?

    Am I still missing something here? This won't work? Why?

  14. #14
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    maybe its not outside the box enough but there is always a 2-speed crank or hub
    i would get really tired of changing the chain - especially with the adjustment precision required of median drivetrains


    Quote Originally Posted by deVries View Post
    Yes, I agree, I don't fully understand. I saw a YT video that shows the B adjustment here:

    https://www.youtube.com/watch?v=YjgBtCObYDY

    What I'm wondering is why can't I just notate the B adjustment "measurements" that are different between the two CR's to get each one to work separately, and, then, just do "monkey see monkey do" to get back to those same settings and adjustments by mimicking and repeating exactly what I did initially to get each CR separately to work???

    Once I know the initial two different settings, then why can't I just readjust the B setting and gap differences between the two CR's that are correct to use for each unique CR?

    Btw, I do appreciate your help, and I'm not being argumentative or hard headed here. I'm perfectly happy if this won't work-out.

    But it seems obvious to me if the chain length "wrap" issue can be balanced-out by not using the 50t cog and using the same identical chain [same length], gaining maybe 10t for a larger CR, then I'll just need to change the B "gap" adjustments.

    Yes, I will have to change the RD B "gap" adjustments and the inner large cog L/R shift limiter preventing the 50t cog use, but once I know these "B gap" settings, then why can't I just reuse those same working positions and change these settings accordingly for each CR size each time I swap CR's? Is that soooo difficult to do? It can't be repeated over and over when using the same two different sized CR's?

    Am I still missing something here? This won't work? Why?

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    Quote Originally Posted by deVries View Post

    Am I still missing something here? This won't work? Why?
    The B-gap on a SRAM 1x RD is also tied to the chain length. Forget the overall capacity, forget the largest cog, i'm talking about the B-gap.
    When you put on a larger chainring it has the same effect as shortening the chain. It will screw up your B-gap in every single gear. You can compensate with the B-screw, and there is a bit of room for error since the system has to work on a full suspension, but a 10 tooth jump at the front is just too much.

    The whole system is designed around a specific chain length and specific cassette size. And 1 chainring of course.

    If this doesn't make sense it will when you get the groupset.

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    Quote Originally Posted by HollyBoni View Post
    The B-gap on a SRAM 1x RD is also tied to the chain length. Forget the overall capacity, forget the largest cog, i'm talking about the B-gap. [...] You can compensate with the B-screw, and there is a bit of room for error since the system has to work on a full suspension, but a 10 tooth jump at the front is just too much.
    The B Gap is adjusted by using the largest 50t cog. There are no other cogs used for B adjustment, so I should gain back plenty of "B Range" for adjustment by never even using that 50t cog. Do I need a longer adjustment bolt?

    Plus, I think a 38t CR are available with 50t cog, standard CR size options, so that should allow for at least a 46t CR to be used when only accessing the 42t rear cog.

    Quote Originally Posted by HollyBoni View Post
    The whole system is designed around a specific chain length and specific cassette size. And 1 chainring of course.
    What is the largest CR size that will work with SRAM 12s? That is the limit, right? Unless, one doesn't use the 50t cog, and, then, theoretically that difference could be added on by another 8t+. Why? 50-42=8t more. Right or ?

    SRAM PG-1230: 11-13-15-17-19-22-25-28-32-36-42-50

    I just checked and X-SYNC™ 2 Eagle™ CR's can be bought up to 38t, so, in theory, one might be able to use a 46t CR, IF and ONLY IF, when not using the 50t cog, and, instead, using the 42t cog.

  17. #17
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    You are focusing on the 50T for some reason. Yes, you adjust the B-gap there, but every single cog on the cassette needs the correct B-gap not just the 50T. There is no such thing as "B range" and you can't gain any "B range".
    You need the correct distance between the upper pulley and each cog on the cassette (aka B-gap) and for that you need the correct chain length AND the correct B screw adjustment. You won't have the correct chain length, because you are planning to use two DIFFERENT size chainrings, and these two different size chainrings would each require two different length chains.

    Your problem is not the chainring size itself, there is no limit. It's the DIFFERENCE between the TWO chainring sizes you are planning to use with your 1x specific drivetrain.

    I'm sorry but I can't explaing it any better. You already bought the groupset, try to make it work with a 2x.

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    Quote Originally Posted by HollyBoni View Post
    You won't have the correct chain length, because you are planning to use two DIFFERENT size chainrings.

    Your problem is not the chainring size itself, there is no limit. It's the DIFFERENCE between the TWO chainring sizes you are planning to use.

    I'm sorry but I can't explaing it any better. You already bought the groupset, try to make it work with a 2x.
    Unfortunately, I'm confused, so I thought by using the same chain length, by not using the 50t cog, then I would only have to change the B Gap adjustment when using two different CR sizes.

    According to you, I'm mistaken, and I'm willing to believe you. I have no experience doing this mechanically, so I'm limited by that SRAM YT video.

    Thanks for trying to explain this to me. I'm obviously confused by my own misdirection of focusing on the wrong problem/solution combination. Maybe I'll find a good YT video that can show the problem you're talking about.

    Thanks for trying...

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    Quote Originally Posted by HollyBoni View Post
    You won't have the correct chain length, because you are planning to use two DIFFERENT size chainrings, and these two different size chainrings would each require two different length chains.
    This is where I must be confused... I thought I could use the same chain for both CR's, because I'm not using the 50t cog. That's WHY I'm focused on not using the 50t cog, because it allows me to use the same chain length for two different sized CR's. Why not?

  20. #20
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    So why not get a drivetrain designed for 3 rings?
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    Isn't Shimano XT 11 speed avail in 1x, 2x, and 3x setups?

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    Anything less than 28x50 and you might as well be walking. That is pretty low gearing (and the smallest that will fit on my Epic). Spinning out is an issue I don't understand for people who are not racing pro. At the speeds you will start spinning out you are already going downhill on smooth, level ground. You are not producing that kind of power on flat ground to sustain 28x10 speeds for long. I am on a 32t with Eagle and I spin out about the same time I need to just tuck in, because the energy exertion at those speeds (downhill on pavement) is incredibly high for a marginal speed gain due to wind resistance. And I have a reasonably high power output with even better endurance.

    So why not just run a 28 with Eagle and be done with it?

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    Quote Originally Posted by frdfandc View Post
    Isn't Shimano XT 11 speed avail in 1x, 2x, and 3x setups?
    Quote Originally Posted by J.B. Weld View Post
    So why not get a drivetrain designed for 3 rings?
    That was my initial intention... But when I posted a thread topic about my "build" from a bare frame, very experienced people were telling me to go 1x 12s.

    I'm willing to give it a go/try, but I will need to use two different sized CR's in 1x usage -not 2x. I don't need a CR lower than 34t/36t, but sometimes I'll want to switch over to a 44/46. I should be able to do this with the identical chain when NOT using the 50t rear cog, because I'm not going out of the "design range" of the RD to mange this 10t difference.

    I will have to adjust the B Gap setting, but I'm told there won't be enough adjustment range or ability by HollyBonni to get this to work. This person believes I can't use the same length of chain, and this is what I don't understand. Why not?

    Why not... IF I don't use the 50t cog, then it frees up enough teeth to use a larger CR in front by at least the same number of teeth lost in the rear cog between the 50t-42t=8t more I can use in front. So, this should allow for me to use an 8t-10t larger CR in front without having to use a different chain. I should be able to use the identical same length chain.

    According to HollyBonni this is "where" I'm mistaken. But. Am I???

    I've already admitted I don't fully understand, so I'm willing to accept I've made a mistake in my understanding.

    Maybe someone can point me to a YT video or article that explains why this won't work?

    I posted a link about B adjustment made by an official SRAM YT video in a previous post, and I found this one that is done by a home mechanic:

    https://www.youtube.com/watch?v=Ly4wDlMWR9o

    Btw, my Fat bike is a hardtail w/rigid fork and a 20-1/2 inch chainstay. It's geometry is obviously not setup for difficult trails or single track, etc. Should do fine on pavement [used for +80% of time] and dirt/gravel bike paths and unpaved roads or beach sand. It's not for steep hill climbing or rough off-road use.

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    Quote Originally Posted by Sidewalk View Post
    So why not just run a 28 with Eagle and be done with it?
    You're misreading the gearing I need. The lowest gearing I need is 34/36t CR on a 42t cog, and I'll need higher gearing sometimes with a 44/46t CR. These are estimates, but I'm probably correct.

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    Btw, I just realized I have a track style slotted rear dropout. Doesn't this mean I can easily adjust the chain length varience between different front chainring sizes depending on where I lock down the rear axle inside that track slot???

    This is another way to adjust for chain slop or slack or too tight and taught, right?

    See pic here for example of track style dropout:

    https://framebuildersupply.com/produ...hoCj3EQAvD_BwE

  26. #26
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    Quote Originally Posted by deVries View Post

    See pic here for example of track style dropout:

    https://framebuildersupply.com/produ...hoCj3EQAvD_BwE


    Where will you mount the derailleur?
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  27. #27
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    Quote Originally Posted by J.B. Weld View Post
    Where will you mount the derailleur?
    Name:  rear dropout 1.jpg
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    DR2014 - steel Frame Components for Horizontal, Rear Dropout 70 degrees relieved hanger opener

  28. #28
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    And that dropout will get you a couple of teeth adjustment on chain length and you need at least 10. You keep saying over and over that you are willing to listen to people if you are wrong but everyone tells you it won't work and why but you keep arguing. You've bought it, use it how you want, see how it works, quit trying to get people here to say it will be fine.
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    Ah, the one you linked was an actual track dropout (no hanger)
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    Quote Originally Posted by sryanak View Post
    And that dropout will get you a couple of teeth adjustment on chain length and you need at least 10. You keep saying over and over that you are willing to listen to people if you are wrong but everyone tells you it won't work and why but you keep arguing. You've bought it, use it how you want, see how it works, quit trying to get people here to say it will be fine.
    If I gain back almost 10 cog teeth [to be exact 8] in the RD by not using the 50t cog, then I'm not going beyond the design capacity of what the RD is designed for. The same chain length can be used even though the front CR is a different size, because I'm not going beyond the design capacity of what the RD can handle by not using the 50t cog.

    Whether or not the B Adjustment can be changed enough to work with the two different sized CR's, is a question I do NOT know the answer to. I've never put forward the assertion that my idea will work, but I think it MIGHT work.

    I also know full well many, if not most, people think my idea will not work or is too much of a PITA to do. I agree.

    I do NOT intend to attempt this until AFTER I have plenty of experience with 1x 12s, hopefully, successfully, and, then, IF I need more high gear range I'll consider my options. I've since found the Oneup Switch CR system that allows for quick and easy change-out of the CR, so I think this may have solved my problem to not have 2x CR's "ready to run" and already mounted.

    This is my current plan that I posted in the Fat bike topic:

    I've taken into consideration everyone's advice to not do 3x or even 2x, and I ended-up ordering Sram NX 12s w/DUB. Also, ordered the Aeffect too just in case I want to do some crazy experiments, but I'm thinking I probably won't have to. Why?

    I found-out about the Oneup's Switch quick swap CR system, and I ordered that for the DUB and Aeffect. These allow me to swap out CR's quickly between 28t up to 36t, so I think these may workout for quick swaps and no need for 2x or 3x.

    Has anyone tried Oneup's Switch CR system? Comments?

    https://www.oneupcomponents.com/coll...lacement-rings

    I ordered the 34t/36t today, so I can report back later how well these work. At least their prices are lower vs Race Face and other similar products, and their quick switch system is fantastic if it works as well IRL as this idea is in theory.

    There's an excellent chance I won't need a larger CR than 36t, so I won't have to go with another type of CR if the Oneup Switch system works well.

    Yes, all you guys are right that 12s offers plenty of high/low gearing range, and since this is not a touring or high speed long ride roadie bike that needs more closer gears...

    I may have the solution. We'll see. I'll report back what happens...

  31. #31
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    Why don't you just return the groupset or cancel your order? Seriously. This makes zero sense.

    You talk about triples in your first post, then you say you need a 46T, and now you say you won't need anything bigger than a 36T.

    Have you even used a gear calculator? You run the numbers you want, and you order a groupset that can do it, not just blindly order a 1x12 because everyone on the internet said so.
    If I tell you to jump off a bridge...

    You probably just spent more money than what a decent 2x or 3x groupset would have cost. Not just that, all those parts and what you want to do might not even work.

    I'm all about interesting and out of the box ideas but this... You're trying to solve a problem that you created for yourself.
    I don't get it.

  32. #32
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    Quote Originally Posted by HollyBoni View Post
    Why don't you just return the groupset or cancel your order? Seriously. This makes zero sense.

    You talk about triples in your first post, then you say you need a 46T, and now you say you won't need anything bigger than a 36T.

    Have you even used a gear calculator? You run the numbers you want, and you order a groupset that can do it, not just blindly order a 1x12 because everyone on the internet said so.

    If I tell you to jump off a bridge...

    You probably just spent more money than what a decent 2x or 3x groupset would have cost. Not just that, all those parts and what you want to do might not even work.

    I'm all about interesting and out of the box ideas but this... You're trying to solve a problem that you created for yourself.

    I don't get it.
    Your response "above" is perfectly understandable. I sympathize.

    The link below is to the other thread about the bike frame and proposed build ideas that I posted before this one, and it explains in more detail about the bike and its purpose. There are even pics of the exact frame with it built-up as a Fat bike, so you can see what it looks like.

    https://forums.mtbr.com/fat-bikes/pl...e-1093180.html

    The problem with configuring the gearing setup is I have two different sized rim/wheel sets with one using narrower rims for 2-3 inch tires and the other using 100mm rims and 4+ inch Fat tires.

    I did some further checking on the overall diameter of these two wheelsets with inflated tires, and it seems I MAY not need a CR of about 44t. This was not my initial "finding", but I'm prepared to go there IF necessary. With Oneup Switch I will not have to use 2x CR's, because I can quickly swap-out to a different size CR. IF I need a larger CR of about 44t, then I can use a spider adapter for my Aeffect to get there. Or, I might be able to modify a CR using a dremel tool to cut-out the openings to fit the Oneup adapter.

    I can see you're paying close attention to what I'm writing, since it is strange I'm backing down from using the 44t CR. IF you read that other thread closely, then you will see very experienced Fat bike riders and builders suggest I go with 1x 12s.

    I do respect their expert opinions, and, so, yes I'm going with their advice to begin with. I'm willing to experiment and lose some money to have fun playing with BSC ideas that may or may not work, but I'm starting with a known 1x12s system that will work to begin with.

    I think that's an excellent idea, if I say so myself, before I jump off the deep end into BSC experiments. Bwahahaha!

  33. #33
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    Yeah the other thread is gold too.

    Quote Originally Posted by BlueCheesehead View Post
    The answer is simple:

    1.) buy it
    2.) install it
    3.) break it
    4.) you then have two choices:
    a.) Learn from the experience
    b.) go back to step one and repeat

    Sooner or later you will learn.

    I too am tapping out from this topic.

    I am done humoring, it is in fact a stupid idea that will fail.
    Quote Originally Posted by NYrr496 View Post
    Or go 2x11 Shimano.
    Someone talks about their buddy's positive experience with GX Eagle and you go with an NX 11-50 instead of a 10-50...

    Amazing.

    You don't need to "experiment", and you don't need to think "outside the box" when you could just buy an off the shelf product that would do what you want out of the box. You're just making life harder for yourself for no apparent reason. Not sure how you don't see that.

    Anyways, once again good luck!

  34. #34
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    Quote Originally Posted by HollyBoni View Post
    Someone recommends you 1x12 and you go with an 11-50 instead of a 10-50...

    EDIT: Someone talks about their buddy's positive experience with GX Eagle and you go with an NX 11-50 instead of a 10-50...

    Amazing.
    Everyone "there" is recommending 1x12s Sram rather than other ideas/choices -including your quoted guys above. It's what they are switching to and are building now or recommending. The NX is lowest entry cost w/o XD, so that was my only choice to save money w/o XD.

    I'm guessing a 34/36t CR will work-out just fine. We'll see.
    Quote Originally Posted by HollyBoni View Post
    Yeah the other thread is gold too.
    Glad I could provide you with "the gold". No coal in your stocking. LOL.

  35. #35
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    Thing is, that 10T cog would have given you a bunch more range, and this whole discussion is about range.

    The money saving part doesn't really make sense either considering you already bought an Aeffect and the Oneup thingy before the groupset even arrived.

    Again, burning more money for an inferior solution. But of course do as you please. Just don't open more threads asking for confirmation on your "crazy ideas".

    So I have this idea...

    I want a bike...

    Get this...

    With square wheels!

    WHOA

  36. #36
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    Quote Originally Posted by HollyBoni View Post
    Thing is, that 10T cog would have given you a bunch more range, and this whole discussion is about range.

    The money saving part doesn't really make sense either considering you already bought an Aeffect and the Oneup thingy before the groupset even arrived.

    Again, burning more money for an inferior solution. But of course do as you please. Just don't open more threads asking for confirmation on your "crazy ideas".

    So I have this idea...

    I want a bike...

    Get this...

    With square wheels!

    WHOA
    I'm not sure why you have to be sooo critical and sarcastic? Inferior solution? Nope.

    I'm buying parts that can be easily returned new for refund if I don't use these, and I can use the extra parts for another bike -if needed too.

    Oneup and Aeffect provide me with more options, if needed, so I'm prepared to experiment if need be and not wait around for ordering more parts and shipping time.

    I got super deals on everything, so I'm still well under the cost of a GX upgrade that might still require another CR or two.

    Either way, I can get all the range I need with more options, and I've saved money too. I'm not spending $420 for GX [12-21-18 price] plus the cost of an XD hub or cartridge upgrade and compatible crankset [if needed], when I can save money with more setup options by not buying GX.

    For me, it's all about range, saving money, and having more options! Win, win, win!

    Winning...

    Plus, I can be BSC, if need be, and maybe some of my wacky ideas will work-out or not. Either way, someone(s) will have a good laugh and find the gold. No need to piss on about it.
    Last edited by deVries; 12-21-2018 at 11:56 PM. Reason: clarity

  37. #37
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    Quote Originally Posted by J.B. Weld View Post
    Ah, the one you linked was an actual track dropout (no hanger)
    Now he is going to build his own frame.

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