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  1. #1
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    PLEASE Help Picking Parts for Correct Chainline w/170mm D.O. Fat Cargo Frame

    Edit: I'm going to cross-post what I'm doing here over to the Cargo Bike thread too, because this Fat Bike is being used mainly as a workhorse grocery and carry loads shopper.

    I have NOT bought anything yet, so this is my possible starting point. BUT I need help with choosing components to get the correct chainline, offsets, and "best way" of ideally doing this correctly... like left/right sides of my pedaling is not weirdly offset to one side or the other, because I bought the wrong parts.

    I posted here 5+ years ago, when I was considering Sandman or Fatback. I almost bought frames from them, but I ended-up getting an American Made C-Moly Cargo frame designed for fat tires. It is extremely heavy duty by design, so it is way overbuilt for indestructible use, and I'm not concerned about saving money buying lightweight performance parts to outfit it. I want quality for durability over high performance. It's mostly going to be used on paved roads as a shopping workhorse and some dirt roads/trails but not mountain biking or snow. Occasional beach riding is likely a few times each year at most.

    I had serious health problems and other life altering events that prevented me from doing anything with the bare frame until now, but this detailed post should allow you to help me w/enough info, hopefully.

    Now I need help to complete it. I want durability quality and lower cost, if and when possible, without any concerns about performance with weight savings. Here's what I need help with:

    I have 100mm 26 or 24 inch rims that I will put the fattest tires I can on it. The frame is for a 26" wheelset, but I can't use this size with my short inseam not giving me enough stand-over height. I should not have any tire chain-rub issues in the Shimano 11s cassette, since the rear wheelset could be 24" vs not 26". I might use a 26" wheel in front if my stand-over height will still work ok, and I will choose between a Moonlander or IceCreamTruck fork unless someone has a better idea. I don't want a suspension fork.

    The frame is a symmetrical [non-boost or non-Pugsley] design with 20" chainstay length and track dropouts. The distance from the O.D. of the 100mm wide Bottom Bracket shell measured from its "backside" O.D. [not from center of BB] closest to the chainstay is 3-1/4", so there is plenty of large size chainring clearance.

    Advice is needed for this possible starting point w/better advice and suggestions... and I know most people are getting 1x11 now... so tell me if I'm making a mistake to consider these 2x11 parts on sale at a discount... I'm looking at buying these

    Edit: the crankset noted below cannot work w/100mm BB Shell.

    Shimano components:

    Crankset: XT M8000 Double 11-Speed
    Chainring: XT M8000 Double Chainring, 36/26T
    Front Derailleur: XT M8000 Double

    There is a Problem Solvers clamp-on front derailleur extender that should work for the front derailleur, but I really have no idea what I'm doing here. I have no Fat Bike experience or bicycle mechanic background, so I'm just shooting in the dark here.

    What Bottom Brackets should I consider buying for best offset mods that will work with these Shimano parts [or your recommended parts] for chainline, offset mods, shims, L/R fit, Q-factor, etc.?

    I know shims might be used to offset spacing on the BB, crankarms, chainrings, pedal attachments for Q-factor, L/R pedaling balance, etc., etc. BUT, like I said, I have no experience doing this myself. It's my first build as a complete newbie.

    Can anyone give me some good recommendations for best low cost parts for an ideal chainline without doing the wrong offset mods on the wrong parts? Like maybe using pedal shims to offset the BB offset, etc.

    I need to pick the right crankset, 100mm BB core, chainrings, and pedals considering shims and mods could be done to any of these parts for ideal chainline and Q-factor and L/R pedaling balance. The frame has a 100mm BB threaded shell that should be a "standard size" ready to take whatever BB "core" that will fit into this frame.

    What savings choices should I consider for durability that will put together the best setup with the above "best fit" criteria as a starting point? Maybe you have better parts considerations and/or suggestions.

    Do I need to provide additional information for further help doing this?

    TIA I really want to get this bike completed soon, so I can be riding and not brain farting unable to do this.

    I really appreciate any help you can give me. Thanks!
    Last edited by deVries; 2 Weeks Ago at 12:39 AM. Reason: Correcting for better clarity and mistaken ideas.

  2. #2
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    Shimano cranksets will not fit on a 100 mm bottom bracket unless you go back to the days of square taper bottom brackets. Google fat bike cranksets you should be able to find one that will work. I think going to the 24" wheel will be worse for chain / tire clearance. You are moving the wide tire closer to the cassette and the chain has to angle in to the inner cassette cogs as it goes from front to back. It still may work though. What is the rear dropout width? Need to know that to make any kind of chainline call.
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  3. #3
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    Quote Originally Posted by sryanak View Post
    Shimano cranksets will not fit on a 100 mm bottom bracket unless you go back to the days of square taper bottom brackets. Google fat bike cranksets you should be able to find one that will work.
    I'm hoping for some specific part recommendations, since I don't know jack. Are you suggesting I find the old style square taper BB and use a different crank arm setup? I won't be able to still use the dual geared Shimano crankarms I mentioned, right? So, what would be a better combination to use instead?

    Any specific brands and/or models of square tapered BB's (or other type w/different crank arms -even 1 front chainring if better) you can recommend that are better than others to look for? Or, do you have a better suggestion? I'm not locked into any brand or specific setup at this point.

    Quote Originally Posted by sryanak View Post
    I think going to the 24" wheel will be worse for chain / tire clearance. You are moving the wide tire closer to the cassette and the chain has to angle in to the inner cassette cogs as it goes from front to back. It still may work though. What is the rear dropout width? Need to know that to make any kind of chainline call.
    The chainstay length is about 20". It's 3-1/4" from chainstay to backside O.D. of BB, so you have to add 1/2 diameter of BB shell to that number for total distance to BB center from the chainstay. The rear dropout width is 170mm. I want to use a wide range 11s cassette.

    Thanks for your help and expertise.
    Last edited by deVries; 2 Weeks Ago at 09:05 AM.

  4. #4
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    I missed the 170 in the title of your post.

    OK here goes, keep in mind that there are many items that will work. Amazon has a Sram x.5 GXP Fat bike crankset that will work for you. Get the 100 mm bottom bracket as well and you should be good to go.

    How wide a range cassette are you planning to use? a mid 40 tooth cog coupled to the 22 tooth chainring on a double crankset will give you a very very low gear. Back in the day a typical low gear would be a 22:34.

    What hub and cassette are you planning to use?

    The Shimano cranks you originally specified will not work with a 100 mm bb. I like square taper fat bike cranks but making them work is probably too complicated for where you are. Speaking of which I still think you should google fat bike cranks, and fat bikes in general,and educate yourself. Relying on internet suggestions can get lots of conflicting and some just plain wrong responses. Are there any local bike shops you can talk to?
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  5. #5
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    Who made this frame? Specs or pics?
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    Quote Originally Posted by sryanak View Post
    I missed the 170 in the title of your post.

    OK here goes, keep in mind that there are many items that will work. Amazon has a Sram x.5 GXP Fat bike crankset that will work for you. Get the 100 mm bottom bracket as well and you should be good to go.
    I checked that part and its specs say this: "Optimized Q-factor for 68/73mm shells with a 49.5mm chainline"

    I have a 100mm BB Shell paired with a 170mm rear dropout width and want to use a 10/11s cassette.

    Edit: the math is wrong below, because I'm not accounting for the overlap of the cassette sliding onto the hub. Anyone know how to do this correctly?

    How to calculate my chainline? Is this formula correct? What am I missing here?... 170mm [rear dropout] - 100mm BB Shell Width = 70mm and 70/2 = 35mm + 1/2 x Cassette Width 37.2mm+ [it's wider than this number] = 53.6mm for the middle gear chainline distance I'm looking for. BTW, I have no idea IF this is correct?

    Is "the above" chainline formula correct? It's just my idea, so I don't know if I'm correct or not??? I'm probably missing something or ??? Please correct me.

    [The above calculation is almost certainly wrong, because I'm not accounting for the distances of overlap where the cassette attaches onto the hub.]

    Quote Originally Posted by sryanak View Post
    How wide a range cassette are you planning to use? a mid 40 tooth cog coupled to the 22 tooth chainring on a double crankset will give you a very very low gear. Back in the day a typical low gear would be a 22:34.
    I won't be using this bike for single track or mountain biking or snow. It's mostly for shopping on road use but might be ridden down the beach and on dirt, etc. There is a dirt trail and dirt field I will go down very often too, but it's a level section. I have moderate hills for road use with some grocery loads to pull.

    Based on this planned use what do you think would be my ideal gears? I'm not interested in pedaling this bike past 18mph a on level road, because I won't have the strength to go faster anyway.

    Quote Originally Posted by sryanak View Post
    What hub and cassette are you planning to use?
    I'm willing to sink more money into these parts, but only for durability and solid shifting -I don't care about saving weight. Would consider a higher end hub for durability and strength. I've heard of Hadley or a lower cost DT Swiss. I don't want to use an XD driver hub unless there is a great price/deal on a cassette match that requires it.

    What do you suggest for the hub and cassette brand and gear range for my intended use [noted again in this post and previous posts too]?

    Quote Originally Posted by sryanak View Post
    I like square taper fat bike cranks but making them work is probably too complicated... Are there any local bike shops you can talk to?
    I'm trying to learn as quick as I can before talking to a bike mechanic. Fat bikes seem more of a specialized topic, since it's a newer concept for cycling. My LBS will not be working on this kind of bike normally, so I need to learn a lot myself too.

    Maybe there is a good reason to use the square tapered BB/crankset considering I might need to use shims/spacers to get this setup to work better???
    Last edited by deVries; 2 Weeks Ago at 06:51 PM. Reason: Noting a probable mistake in this post.

  7. #7
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    Quote Originally Posted by NYrr496 View Post
    Who made this frame? Specs or pics?
    PLEASE Help Picking Parts for Correct Chainline w/170mm D.O. Fat Cargo Frame-screenshot-81-.jpg
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  8. #8
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    I would use a Raceface Aefect crankset for a 170mm rear wheel with a single Wolftooth ring and a Shimano 11 speed XT cassette. Easy.
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    Quote Originally Posted by NYrr496 View Post
    I would use a Raceface Aefect crankset for a 170mm rear wheel with a single Wolftooth ring and a Shimano 11 speed XT cassette. Easy.
    Thanks for the suggestion. I may end-up doing this, but I'm first going to try two chainrings up front to begin with.

    I'll consider the Raceface Aeffect using two chainrings, but I'm curious if anyone knows about using the Surly MW crankset setup for the Moonlander? I think it has a wider chainring size selection than Raceface for larger sizes when using two chainrings???...I don't know. Certainly the chainline will be very different and more outward w/Surly.

    I wonder if using a triple chainring would be a good idea too, BUT just use ONLY two of the outer chainrings for shifting. This would allow for altering the chainline further outward, avoiding any tire/rim rub, and it's what Surly is doing from my understanding. Using the middle chainring for lower gears in the back cassette would give better alignment and less twist when engaging the larger sized cogs.

    Are any triple chainrings designed for using with a 170mm RDO w/100mm BB?

  10. #10
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    You are making this way to hard. The x.5 fat bike crankset is for 100 mm bottom brackets and 170 rears. I suspect the 68/73 optimization language is for their non fat version. I also suspect the cranksets are identical only the bottom bracket spindles have been changed. A crankset with good chainline on a 68 mm bottom bracket and 135 rear end will work on a 100 mm bb and a 170 mm hub. both ends got about 35 mm wider and a 190 rear end uses an effective 120 mm bb so both another 20 mm wider.

    For the level riding you plan on doing do as NYrr496 said get a single affect and an 11 speed rear and maybe a 28 tooth front chainring. Get the Race Face bottom bracket cups to match the crank. This is not rocket science don't sweat it quite so much. The hubs you mention are fine, both will work.

    Forget I mentioned square taper. They will take some fiddling. The modern fatbike specific cranksets will be mostly plug and play.
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  11. #11
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    Have you talked to the guys that built your frame. They could be a good source on what parts to use.
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  12. #12
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    Quote Originally Posted by sryanak View Post
    You are making this way to hard. The x.5 fat bike crankset is for 100 mm bottom brackets and 170 rears. I suspect the 68/73 optimization language is for their non fat version. I also suspect the cranksets are identical only the bottom bracket spindles have been changed. A crankset with good chainline on a 68 mm bottom bracket and 135 rear end will work on a 100 mm bb and a 170 mm hub. both ends got about 35 mm wider and a 190 rear end uses an effective 120 mm bb so both another 20 mm wider.
    I do overthink when I'm trying to learn new concepts and problems. It's just my OCD nature, and it's the only way I tend to learn AND remember. This can be annoying if you think I'm "debating" anyone's ideas, but I just have to explore all options to fully understand. For example, here is something I found-out when looking at BB.

    In my OP I mentioned using the dual chainring M8000 crankset, but you said it won't work with a 100mm BB. The Shimano specs are:

    Cassette Compatibility: 11
    4-Arm Chainrings: Yes
    Bolt Circle Diameter: P.C.D. 96/64mm
    Crank Arms: Hollowtech II Technology
    BB Shell Width: 68, 73mm

    Now, I'm confused, because looking at quality made Raceface 100mm BB for fatbikes it says these can be compatible with some 24mm Shimano Spindles. It does not specify which ones, but the M8000 crankarms use 24mm spindles. My guess is that the spindle length on the crankarm will not be long enough to place the spider in the correct offset position??? Spindle length extender coupling anyone??? See, this is how I overthink things. Lol. It's compatible with 24mm spindle diameter cranksets, like Shimano HollowTech II and the M8000. Where is my thinking going wrong now, since you did write this too:
    Quote Originally Posted by sryanak View Post
    A crankset with good chainline on a 68 mm bottom bracket and 135 rear end will work on a 100 mm bb and a 170 mm hub. both ends got about 35 mm wider and a 190 rear end uses an effective 120 mm bb so both another 20 mm wider.
    Quote Originally Posted by sryanak View Post
    For the level riding you plan on doing do as NYrr496 said get a single affect and an 11 speed rear and maybe a 28 tooth front chainring. Get the Race Face bottom bracket cups to match the crank. This is not rocket science don't sweat it quite so much. The hubs you mention are fine, both will work.
    I'm usually acting outside-the-box. The trendy thing is to have a 1x11s, for good reasons too, like simplicity, but I'm going to start with 2 chainring gears upfront to begin with. Then, I can always cut back to 1 speed. I guess I need to choose between the Aeffect and the Chester and maybe a Surly MW too?

    Hey, I think I've narrowed this down to one of these three. Since I'm starting with a 2 chainring setup, which of these three would you choose and why?

    Thanks for your time and help with this. I do appreciate your suggestions very much. I'm just a bit stubborn about wanting to go with a 2x 10/11s setup to begin with.

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    Quote Originally Posted by sryanak View Post
    Have you talked to the guys that built your frame. They could be a good source on what parts to use.
    It was a one-man operation, and the designer changed it differently than what I have. I don't think he actively sells these now. He moved to another state, and I don't have his contact info anymore. I doubt he will remember what parts were tested for this frame that was built over 4-5+ years ago. But I do think there are more pics online, so it might be possible to magnify the image to see what parts are on the frame too. I'm pretty sure he used Surly for the crankset and BB.

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    I have a 2x10 drivetrain on my main fat bike right now because it's how I originally built the bike. I've been waiting for either the cassette or the rear derailleur to fail so I can justify swapping to 1x11 or 12. I've been building one by bikes for friends and customers for a few years now and my Krampus is 1x11. It's the way to go.

    I have a Surly OD crankset on two bikes. 33 and 24 on my two by bike and 28 with a bash ring on my beach bike. Great crankset but very heavy. May not matter if you plan on hauling stuff on your bike.

    The Raceface Aeffect cranksets have 24mm spindles and work with Shimano bottom brackets.
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    I just read back and saw you also asked about hubs. Have a look at Bike Hub Store. Don't let the low cost fool you. They come with good bearings and an anti bite freehub, meaning the cassette won't dig in as easily.
    Use an XT cassette so the loads are spread out over the wider webs.

    Have you ridden a fat bike before? I'm speaking from experience here... I'm not the fastest guy in the world. You're overthinking the front chain rings. My Surly cranks came with 36 tooth big rings and I had to change em to 33 to utilize more gears on my cassette. My friend, who is about 90 pounds lighter than me uses the 36 but I'll bet money he never ever goes on the 11 or 13 tooth cogs on his cassette. We're both running 4.8" tires on 80mm rims.

    What rim and tire combo are you planning on running?
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    I am pretty sure the spindle is too short as you say. There really is not a market for specific spindle extenders because there are lots of cranksets that work right out of the box. This is not the early days of fat bikes when everything was sort of make it fit. Not to say there can't still be issues but not so much if you use purpose built stuff and don't try to mix and max manufacturers, at least on parts that have to bolt together.
    As to 2 by or 1 by as NYrr496, so too do I have both. A 2 by 9 and a 1 by 10. The ranges are similar on mine, a bit more high end on the 2 by 9. They both work fine. If you go with a wide range 11 and a 22/36 there will be gears on either end you never use. If you go with say a 12/36 in the back and a 22/36 in the front you will likely use most of what you have. Pretty much the same ratio can be had with a wider range 11 speed in the back and a single 30ish tooth in the front.
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    Quote Originally Posted by sryanak View Post
    As to 2 by or 1 by as NYrr496, so too do I have both. A 2 by 9 and a 1 by 10. The ranges are similar on mine, a bit more high end on the 2 by 9. They both work fine. If you go with a wide range 11 and a 22/36 there will be gears on either end you never use. If you go with say a 12/36 in the back and a 22/36 in the front you will likely use most of what you have. Pretty much the same ratio can be had with a wider range 11 speed in the back and a single 30ish tooth in the front.
    Hey, I really appreciate both of your suggestions and ideas. Both of you have really helped me learn quite a bit, so much so, that if I like using this fat cargo bike w/big tires too, then I'm probably going to get a performance 2nd Fat Bike. The 2nd performance fat bike is where I will seriously consider going w/1x11s.

    Here are some good reasons I'm sticking with either a 2/3 chainring setup in front on this bike.

    Edit: there are no front 3 chainring setups properly spaced for 170mm RDO symmetrical rear wheels.

    1) I'm going to be carrying loads as heavy as a 2nd person on the back rack. I want less side-loads and twist on the chain/cogs to lower the wear and tear factor by having better chain alignment with 2/3 chainrings.

    2) I will use the high/low gearing range extremes more often, so, again, I get better alignment and less wear with 2/3 chainrings upfront.

    3) I want a large chainring upfront for faster higher gears, because I plan on trying an electric hub-motor in a swappable 2nd front wheel that I'll need to use on occasion.

    I didn't mention this before, because I wasn't sure I was going to build the bike with certain setups until today. Now I know I will be able to use the higher gearing with the occasional use of an electric hub-motor too.
    Last edited by deVries; 1 Week Ago at 05:18 PM. Reason: Not going to use 3 chainrings!

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    Quote Originally Posted by NYrr496 View Post
    I just read back and saw you also asked about hubs. Have a look at Bike Hub Store. Don't let the low cost fool you. They come with good bearings and an anti bite freehub, meaning the cassette won't dig in as easily.
    Use an XT cassette so the loads are spread out over the wider webs.
    Thanks again for your help. I'm really enjoying learning from both of you here, and you've helped me out quite a bit.

    Yeah, I checked-out Bike Hub. Is that a Novatech hub??? It might be because it looks like it has the same styling and QR match??? I wonder how easy it will be to get parts for it? I haven't asked them, but someone posted here about trouble getting service parts for the Novatech hubs.

  19. #19
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    Quote Originally Posted by deVries View Post
    Thanks again for your help. I'm really enjoying learning from both of you here, and you've helped me out quite a bit.

    Yeah, I checked-out Bike Hub. Is that a Novatech hub??? It might be because it looks like it has the same styling and QR match??? I wonder how easy it will be to get parts for it? I haven't asked them, but someone posted here about trouble getting service parts for the Novatech hubs.
    Not Novatech. Bitex. Much better. BHS sells bearings and freehubs, axles... I've been using their stuff for a few years now with zero problems. I get lots of requests for them in many of the builds I do.

    Don't do a triple. I PROMISE you'll never use it. Double if anything.
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    Quote Originally Posted by NYrr496 View Post
    I would use a Raceface Aefect crankset for a 170mm rear wheel with a single Wolftooth ring and a Shimano 11 speed XT cassette. Easy.
    The only thing I may change here is going with the Wolftooth Camo setup to aid in dialing in the chainline, which seems to be a concern. I would also go with an elliptical chainring as they do seem to smooth out the power transfer under load.

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    Quote Originally Posted by NYrr496 View Post
    Don't do a triple. I PROMISE you'll never use it. Double if anything.
    That is great advice. I cannot help but think of it as:

    "Don't shoot yourself in the head. If you must shoot yourself, do it in the foot."

    Having changed from 2x10 to 1x11 I can say I would never go back. Chain line is an insignificant issue. One problem I had with a small ring (22t) and a high load was breaking the chain. That is due to the smaller chainring creating a larger crankarm to chain location ratio (longer effective lever arm). Going with a larger chainring and larger cassette cog to achieve the same gear inches moves the mechanical advantage from the front to the back and takes stress off the chain, something the OP may wish to consider when hauling heavy loads. (I tow my disabled son, 140 lbs on a 60 lb tag along and I go 200 lbs+ so my bike sees some good loads)

    I had a 2003 road bike with a Dura-Ace triple. Even with that top of the line setup it sucked.

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    It is difficult to calculate chainline without knowing exactly how the cassette sits on the hub or how the crank mates to the spindle. Some crankset manufacturers publish the chainlines for their cranksets on various bottom bracket widths but finding where that inner cog on an 11 speed cassette sits may be difficult. And then if you do find it, what is the optimum number? I suppose whatever clears the rear tire would be good but going from some calculated chainline to determining sifting quality or chain cog life there just isn't an equation for that.
    Back in the early days of fat bikes it was a semi big deal because we were trying to make parts work that were not designed for fat bikes and 100 mm bottom brackets. Now there are purpose built parts. A fat bike crank from a Sram or Raceface, for example, designed for a 100 mm bb and a 170 rear end will just work with your bike. Double chain ring or single (given the correct spider) will work fine. The only fly in this ointment would be if you use the 24" wheel because that moves the wide tire closer to the rear axle. This may or may not be a problem. It will be less likely to be a problem if you go with a one by crankset since they move the inner cog away from the center axis of the bike. The fact that you are using a cargo bike with relatively long chainstays improves your chances making it work with the smaller wheel since the rear axle is moved away from the bottom bracket.

    Back to the question of the XT 8000 series. It's not just a question of placing the spider at the correct offset. The spindle on those cranks is 35 ish mm too short. It probably won't even reach through the bottom bracket. Several people have tried to make bottom bracket extenders over the years. They seldom hold up. The torque on those axles when mashing ultra low gears is immense. Don't ask me how I know this.
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    Quote Originally Posted by sryanak View Post
    Back to the question of the XT 8000 series. It's not just a question of placing the spider at the correct offset. The spindle on those cranks is 35 ish mm too short. It probably won't even reach through the bottom bracket. Several people have tried to make bottom bracket extenders over the years. They seldom hold up. The torque on those axles when mashing ultra low gears is immense. Don't ask me how I know this.
    Lol. Thankfully, you have given me excellent advice along with everyone else that posted above too, thanks guys, but just to show you how "crazy" I can be I did find this article -snippet below...

    https://bikerumor.com/2013/02/07/hac...-on-a-fatbike/

    Recently, we got a tip informing us that someone had seen a Moots FrosTi out there with a Shimano XT crankset. They had sent some pictures, but with zero information and pictures that really didn’t prove it was a 100mm BB we had little to go on. It didn’t take us long though to stumble on Lloyd Chamber’s cycling blog, that happened to have a gallery of photos of a Moots FrosTi with an XT crank. It just so happens that not only is Lloyd an amazing photographer, he is also quite the cyclist with his fleet of Moots being some of his favorite subject matter among other cycling related photos. There it was, clear as day – a Shimano M780 crankset on a Moots FrosTi.

    [...]

    That is, until I spoke to Lloyd. I had been told by a friend in the know that since the spindle is simply pressed into the crank arm, it might be possible to press it out and have a longer one pressed in. After asking Lloyd about it, the answer I got was “special project for the crank.”

    Hmmph.

    Prying a little farther, it turns out Lloyd was simply being conscious of his connections and was being careful about what he said. Finally, he came back and said that the crank modification was a custom job he had made to his specs by a member of the Shimano staff who prefers to remain anonymous. So there you have it. Possibly one of the only, or very very few XT fatbike cranks on the market with no plans for production. Still cool none the less.

  24. #24
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    Quote Originally Posted by NYrr496 View Post
    Don't do a triple. I PROMISE you'll never use it. Double if anything.
    Lol, I'm crazy, why? I was thinking last night about getting a Fat Sram GX for a double ring, and, then, remove it to put on a triple ring outboard. Then rig-up the derailleur with spacer to reach-out for that 3rd outside ring. Or, use the 2 inner rings with bigger chainrings and allow the 3rd ring to act like a bash retainer. I'm crazy enough to consider these ideas, but I'm hopefully wise enough not to actually attempt it. We shall see... Bwahahaha!

    Yeah, I think I won't be shooting myself in the head, maybe the foot, as someone suggested I might be doing instead...

    Quote Originally Posted by BlueCheesehead View Post
    That is great advice. I cannot help but think of it as:
    "Don't shoot yourself in the head. If you must shoot yourself, do it in the foot."

  25. #25
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    I'm going with an experimental concept, which is to test-out 2x chainrings w/10/11s cassette setups. I'm looking at Sram GX-1400 and Raceface Ride cranksets because of super pricing right now. Also, these can easily run 1x or 2x or 3x, but I'm only looking to do 2x or 1x. There is a lot of chainline placement options by testing these setups, and because I don't know what rims/tires I'll end-up using I'll have lot of flexibility.

    It's probably going to be a month or so before I'm ready to ride, but I'll keep posting here about what I'm learning to hopefully add a bit of useful info to the forum.

    I found some really good chainline wheel/tire w/crankset selection articles and equipment info online, and I'll be posting snippets and links when time permits.

    If anyone knows of some other good flexible chainline crankset/chainring equipment and setup ideas that can be found for excellent prices, I'm on a lower cost budget, then please post those ideas here too. The focus is for 170mm rear dropouts matched to 100mm Bottom Bracket. TIA.

    Does anyone know of exceptional quality BSA English threaded 100mm BB for 24mm spindle to choose over another for $30 to $100 range? Also, what to avoid in that price range too.

  26. #26
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    Don't overthink the bottom bracket. More expensive ones may have better bearings. Buy one that is compatible with your crankset and that is within your budget.

  27. #27
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    Shimano bottom brackets are cheap and excellent. Chris King is expensive and excellent. I have both.

    Your plan sounds solid. Looking forward to your results.
    I like turtles

  28. #28
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    Quote Originally Posted by NYrr496 View Post
    Shimano bottom brackets are cheap and excellent. Chris King is expensive and excellent. I have both.
    Since I am going to be experimenting with the Race Face Aeffect 3x for gearing and chainline and tire/rim match-up for 100mm BB, I've found a lot of negative comments about RF's own 24mm BB saying these don't last and are poor quality.

    I haven't bought the BB yet, so I'm wondering if I could get a better quality BB that will still work with the RF Aeffect. Any ideas or suggestions???

    I don't know? Has anyone used Race Face XC or DH BB for BSA 100mm? I'd rather pay more to avoid lower quality.

    Also, has anyone used an SRAM 12s Fat BB 100mm 170mm/hub setup with TWO different tire/rim widths that could allow for the chainline to be moved inward if using a 40-50mm wide rim vs 100mm rim?

    I mean, does SRAM allow for the chainline to be moved inward if 3rd party cranks, like RF, allow for more chainline adjustment? Just wondering if the left/right horizontal axis of chainline will have much affect on the rear shifting if the front chainline can be moved inward when using narrower rims/tires vs when using a wider wheel/tire set when needed too?

    It's my understanding the main reason the chainline has to be moved further out is just for the fatter/wider tires, but what about using a much narrower rim/tire set too? Any reason to be concerned about chainlines with two different wide/narrower wheelsets?

    Overthinking again? Am I?

  29. #29
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    Your chain line will not change if you were to put narrower rims/tires on the bike. Why? because those wheels will still have the same width hub. The hub is what determines the cassette's location relative to the frame and chain ring(s). The rear spacing of the frame determines which hub width you need. When changing wheels the most you might have to do is a slight cable adjustment for the rear derailleur (re-tune) to account for manufacturing differences between hubs. NO futzing with the crankset is required, NONE.

    When in doubt, Sheldon Brown:

    https://www.sheldonbrown.com/chainline.html

    I would suggest buying this:

    https://www.velopress.com/books/zinn...e-maintenance/

  30. #30
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    If I'm building a bike for myself, I usually use a Chris King bb. If I'm building a customer bike and they don't want to spend CK money, I use Shimano. They work great. I've probably built fifteen fat bikes with Aeffect cranksets and Shimano bottom brackets and zero complaints. I ride with three guys every week and two of them are on Shimano bottom brackets with Aeffects. If there was an issue, I'd know about it.
    I like turtles

  31. #31
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    Quote Originally Posted by NYrr496 View Post
    I've probably built fifteen fat bikes with Aeffect cranksets and Shimano bottom brackets and zero complaints.
    So, Shimano makes a Fat BSA 24mm/100mm BB that works with Aeffect?

    I'm interested.

  32. #32
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    Quote Originally Posted by BlueCheesehead View Post
    Your chain line will not change if you were to put narrower rims/tires on the bike.
    Agreed. I wasn't thinking too clearly near 4am.

    I still have this crazy idea about testing the 12s SRAM with a 3x spider upfront with 3 different chainrings of different sizes. 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?

  33. #33
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    Quote Originally Posted by deVries View Post
    So, Shimano makes a Fat BSA 24mm/100mm BB that works with Aeffect?

    I'm interested.
    The BB doesn't care what width the BB shell is. It just threads into each side of the BB shell on the frame.

  34. #34
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    Quote Originally Posted by bikeny View Post
    The BB doesn't care what width the BB shell is. It just threads into each side of the BB shell on the frame.
    Exactly.
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  35. #35
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    Quote Originally Posted by bikeny View Post
    The BB doesn't care what width the BB shell is. It just threads into each side of the BB shell on the frame.
    As long as one does not care to have to plastic connector tube...

  36. #36
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    Quote Originally Posted by deVries View Post
    Agreed. I wasn't thinking too clearly near 4am.

    I still have this crazy idea about testing the 12s SRAM with a 3x spider upfront with 3 different chainrings of different sizes. 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?
    It is going to be less tolerant with multiple chain rings. The same guidelines will apply with regard to cross chaining. You will NOT want to utilize all 12 cogs from the inner and outer rings.

    Are you still thinking of running a 24" rear wheel? That effectively lowers your rear ratio as well. That would effectively make a 50T rear cog equal to a 54T cog on a 26" wheel. Put a 28T on the front and you would climb anything you would need to.

    BTW, it looks like Design Logic has updated their frame design with some supplemental seat stays. From your picture that frame utilizes the rack as the seat stay. Not structurally efficient. If I were you I would contact them to see if they could modify your frame and perhaps modify the top tube to give you more stand over.

    Design Logic Bikes, cargo bicycles made in the USA
    Last edited by BlueCheesehead; 1 Day Ago at 12:15 PM.

  37. #37
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    Quote Originally Posted by deVries View Post
    Agreed. I wasn't thinking too clearly near 4am.

    I still have this crazy idea about testing the 12s SRAM with a 3x spider upfront with 3 different chainrings of different sizes. 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?
    The problem with trying to use 3 chainrings with 12 speed is that the rear derailleur will not be able to take up enough chain slack to work in all chainring/cog combinations. You would have to set the chain length so that all cogs are usable when you are in the middle chainring. When you switch to the small chainring, you could use the bigger cogs, but when you shift to the small cogs, the chain would have a bunch of slack and be bouncing around all over the place and hitting things. Then when you shift into the large chainring, you could use the small cogs, but when you try to shift into the bigger cogs, your expensive 12 speed derailleur will get ripped off the frame. And the chainline would be slightly worse that a 3x9 or 3x10 setup just because the outside cogs are further from the center of the cassette. A 3x12 setup will just not work, end of story. It doesn't matter if you shift by hand or with a front derailleur.

    I think you're missing the whole point of 12 speed. Basically, you can get the same spread of gears with a 1x12 that you can with a 3x9 setup. You are trying to build too much versatility into the drivetrain, as some point it just can't do everything and instead doesn't do anything well.

  38. #38
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    ^^^ He has been warned to not shoot himself in the head.

  39. #39
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    Quote Originally Posted by NYrr496 View Post
    I ride with three guys every week and two of them are on Shimano bottom brackets with Aeffects. If there was an issue, I'd know about it.
    Sounds like you're "the one" for knowing which Shimano BB's I can choose from. Which specific S-BB's do you suggest, and is there anything special/unique about installing or maintaining these to use with the Aeffect? Extra parts or tools, or spacers, etc.

    Why does everyone tend to sell/buy BB's with the tubes for the width of the BB spacing? Advantages? Or, marketing ploy and misdirection?

    TIA.

  40. #40
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    Quote Originally Posted by BlueCheesehead View Post
    ^^^ He has been warned to not shoot himself in the head.
    Agreed. I know now I can't easily [or even possibly] get 3x to work w/12s. Maybe 2x "hacker version" without a front derailleur and manually switch rings based on ride type [hills, flats, faster speed], but run the ride in 1x mode.

    For example, a 2x run as a 1x using 34/36t and a 44t CR, but I'm told the RD may not be able to handle the chain slop??? Plus, the chainline misalignment with one ring not centered, and CR ring size variance causing necessary adjustment on RD too. BUT since I'm not shifting w/FD between CR's, then maybe I could get it really close to the centered CR to allow it to work?

    Still crazy or possible???

  41. #41
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    https://www.jensonusa.com/Shimano-XT...SABEgJnefD_BwE

    Comes with three spacers. You'll need a bb wrench or socket.
    I like turtles

  42. #42
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    Quote Originally Posted by NYrr496 View Post
    https://www.jensonusa.com/Shimano-XT...SABEgJnefD_BwE

    Comes with three spacers. You'll need a bb wrench or socket.
    Thanks. For my 100mm wide BSA threaded BB shell, then do I need to cut the 68/73mm spindle "spacer tube" in half, or it's already split into 2 parts, or is it even usable for my installation? It's confusing, since the link you gave does show the adapter tube that , I assume, cannot work or fit across my BB shell 100mm width.

    I see the Chris King BB needs a tube kit to work, so KC says, so what do I do with this Shimano "missing" or wrong tube length?

    Thanks.
    Last edited by deVries; 1 Day Ago at 01:20 AM.

  43. #43
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    Quote Originally Posted by deVries View Post
    Thanks. For my 100mm wide BSA threaded BB shell, then do I need to cut the 68/73mm spindle "spacer tube" in half, or it's already split into 2 parts, or is it even usable for my installation? It's confusing, since the link you gave does show the adapter tube that , I assume, cannot work or fit across my BB shell 100mm width.

    I see the Chris King BB needs a tube kit to work, so KC says, so what do I do with this Shimano "missing" or wrong tube length?

    Thanks.
    You just don't use the tube. You are correct that it is too short to span the wider 100mm BB shell. The tubes don't really do much, as it's all inside the BB shell and not exposed to the elements. Maybe if you are constantly riding in wet weather and water makes it's way down the seat tube it helps protect the spindle and bearings?

  44. #44
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    Quote Originally Posted by deVries View Post
    Agreed. I know now I can't easily [or even possibly] get 3x to work w/12s. Maybe 2x "hacker version" without a front derailleur and manually switch rings based on ride type [hills, flats, faster speed], but run the ride in 1x mode.

    For example, a 2x run as a 1x using 34/36t and a 44t CR, but I'm told the RD may not be able to handle the chain slop??? Plus, the chainline misalignment with one ring not centered, and CR ring size variance causing necessary adjustment on RD too. BUT since I'm not shifting w/FD between CR's, then maybe I could get it really close to the centered CR to allow it to work?

    Still crazy or possible???
    Yes, still crazy. The problem is the amount of chain the rear derailleur can take up. I wasn't able to fin the exact spec, but the SRAM Eagle derailleurs are made to be used with a 10-50t cassette, so the max slack it can take up is about 50-10=40t. Maybe it can take up 2 or 4 more? But if you are using 34t and a 44t chainrings, it would need to take up 10t more slack when you switch chainrings. Again, it doesn't matter how you switch, by hand or with a front derailleur. The only way to make it work would be having 2 different chains of different lengths that you swap in depending on what chainring you are using. It's just not worth it, the range of a 1x12 is so wide already.

    You keep focusing on chainline, which is the least of your problems. Getting the 2 chainrings centered on the cassette should be no problem.

  45. #45
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    Correct. Just omit the tube.
    I like turtles

  46. #46
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    Quote Originally Posted by bikeny View Post
    Yes, still crazy........

    You keep focusing on chainline, which is the least of your problems. Getting the 2 chainrings centered on the cassette should be no problem.
    And not only that but if the chain rings are off by a little bit it just doesn't matter.

    deVries you need to read Sheldon Browns thoughts as stated earlier. And any other bike mechanics reference you can find. These issues are simple in some ways and complicated in others. Getting a good understanding from necessarily short and often contradictory MTBR posts is going to be difficult.
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