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    Soma Riff belt drive build

    Hi!

    I was inspired by Rider's build:
    https://electricbike.com/forum/forum...v-custom-build

    And decided to base mine off it. I'm planning on making a battery box similar to this:
    https://endless-sphere.com/forums/vi...=6&t=40537

    I'm currently prototyping it in steel track but have borrowed a sheet metal brake and will probably make the real thing out of 0.8 - 1mm steel with 1mm aluminum sides from some signs a buddy has. Thats so I can weld nuts to the steel part to bolt on the side panels. the current plan is for the box, frame, and fork to be powdercoated a single color. I picked the ECR fork because of all the mounting possibilities. This bike will end up with pretty decent cargo capacity.

    The step that I'm working on right now is the battery and the enclosure. As of now it will be one of the luna triangle packs although I'm open to other suggestions. If there are better BMS's to use than the ones packaged with their triangle packs i'm open to doing separate banks of batteries inside there.


    I was hoping to use some sort of waterproof case mounted charge connector like a Rosenberger RoPD but the only place I can get one is Digikey and they are selling the assembly for over $100! So my first question is, what kind of other connectors should I consider? I think someone on shapeways posted a case mount for an XT-90.

    I want to keep the wiring on the bike as clean as possible and may use cable glands to hide stuff inside the case if that helps. So packing the battery to motor connection inside might be nice.

    I am hoping to make charging as dead simple as with my Zero FX motorcycle that I'm selling and replacing with this bike. As in park it, plug it in, walk away reasonably sure that my house isn't going to burn down. I was going to wire in one of luna's on / off switches. They recommended that I unplug the battery output before charging the battery. I asked if turning the bike off via the switch was good enough and they said no. What do you guys think? What is the actual risk of charging the bike while the battery output is still connected regardless of if an on off switch is gating the battery?

    Thanks,

    Gerry
    Last edited by Overkill; 09-17-2018, 05:51 PM.
    Intro, Belt Driven Build

    #2
    Great to see another belt drive eMTB build. The key with belt drive builds is the ability to get the belt line straight; same offset from frame center in the front and rear. The easiest way to do that is to use a Sturmey-Archer CS-RK3 3spd that lets you adjust the belt line on the cassette mount on the IGH or use an expensive Rohloff that has a large offset.

    I'm sold on the 48V Sanyo-Panasonic GA battery packs with quality BMS and use an XT-90 connector for the output with the smaller version for the charging cable. I never unplug my output wires when charging with the display powered off. Wasn't aware of the recommendation you state either. I have also turned on the power while it was charging (I don't recommend that) to see what the voltage indicator read (battery charge level or charge going in from the charger) without any problems.

    When using a triangle battery pack within a frame bag all I do is unzip the bag, plug in the charger and walk away. I do like the 80/90/100% chargers. I charge to 80% and top off before I go ride. That still takes some time planning for that last 20%, but theoretically should extend the battery life if I don't end up riding soon after the initial 80% charge. If that's all I need for the next ride, I don't top it off. I will do periodic battery balancing top-offs if I've ridden several rides without topping off.

    I really like belt drive zero maintenance applications and hope to convert my Surly ECR to belt drive if I ever purchase a Rohloff IGH for it. Currently I'm having to much funny riding it to take it apart and have a frame break added. That's the great thing about many Soma frames, you can order them with the frame break already installed.

    Subscribed!
    Last edited by Rider; 09-18-2018, 08:46 AM.
    MOVING BACK TO PEDAL...
    2020 Banshee Paradox V3 1x11 (pedal)
    2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

    Comment


    • Overkill
      Overkill commented
      Editing a comment
      Thanks Rider! you are the reason this build is happening :) I kind of suspected that the disconnect the battery warning was a conservative response. I suspect that the real problem is drawing power from the battery at the same time its charging. the display i'm using also has an on / off switch so between that and the master cutoff i should be ok.

    #3
    I like your idea of installing in-line external on/off switch for the main battery out and building in an external charging plug for your solid triangle battery box. Boat switches may be a good choice, as they have a rubber covering that keeps out water. You might have to hunt for a waterproof two-prong plug with attached waterproof cover for the external charging port, but I bet they do exist.
    Last edited by Rider; 09-19-2018, 03:39 AM.
    MOVING BACK TO PEDAL...
    2020 Banshee Paradox V3 1x11 (pedal)
    2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

    Comment


    • Overkill
      Overkill commented
      Editing a comment
      Marine is a great idea! I went to Defender Marine and poked around. Interestingly, their switches have different current ratings for different voltages. Like 20A @ 12V and 15A @ 24V. I emailed Grin about this switch and they seemed to think that only current mattered not voltage:



      Defenders site would seem to imply that as voltage goes up current rating goes down.

      i was able to track down a Rosenberger ropd connector from mouser for $20 more than what Luna sells it for but that’s still a hell of a lot for a connector and cable. But their return policy is 30 day no questions asked so I’ll poke around Defender to see if they have connectors that might work too. I’ll post if I find a good one
      Last edited by Overkill; 09-19-2018, 10:20 PM.

    • JPLabs
      JPLabs commented
      Editing a comment
      For DC switching, current does affect voltage. For AC, the zero crossing helps quench switch arcing. DC arcs worse. Higher current drives more inductive kick when breaking the circuit, thus more arcing. A physical DC switch must be designed to prevent arcing, thus the ratings are current-dependent.

      Current is not all that matters for DC switch capacity. Too much voltage, at that current, and it will sustain an arc! Very important consideration!!

    #4
    THIS IS A POST I MADE IN THE PAST SOMEWHERE:

    Bafang BBS02B belt drive is possible with 68mm (and possibly a 73mm) BB and a wide enough belt line rear hub. Here's my Soma B-Side Gates Carbon Drive build. It has key belt line measurements in it.

    I just made up a quick reference chart for some key Bafang BBS02B chain/belt line issues in preparation for my next build.



    ~55mm = BBS02B on 68mm with current spider adaptor and 50T Gates on the Soma B-Side

    54.7mm = Rohloff 14spd speed hub chain/belt line

    44mm = Sturmey-Archer RX-RK5 5spd (42-46mm range depending on cog)

    ~22mm = BBS02B spider mounting surface to right BB edge

    ~56mm = BBS02B on 68mm BB spider mounting surface to frame center line

    ~58.5mm = BBS02B on 73mm BB spider mounting surface to frame center line

    ~10mm = 42T Lekkie Bling Ring inset from BBS02B mounting surface

    ~12mm = BBS02B BB right edge to 42T Lekkie Bling Ring chain line

    ~46mm = BBS02B on 68mm BB with 42T Lekkie Bling Ring chain line

    ~48.5mm = BBS02B on 73mm BB with 42T Lekkie Bling Ring chain line


    In short, the best rear hub for a BBS02B conversion is a Rohloff with its' wide chain/belt line. If a 3spd is desired, the Sturmey-Archer CS-RK3 gives you a rear cassette to align the chain/belt. And, the smallest Gates front belt ring that clears the BBS02B gear reduction housing is a 50T.

    One always has to consider the chain stay clearance as well. If using a 73mm BB, you can face off as much as you can until the BBS02B is right on the chain stay. In order to make a 73mm a 68mm, only face off half the difference or 2.5mm. The left side can stay where it is and you end up with an offset 70.5mm BB.

    If you have access to a machine shop, then you can combine a 42T Lekkie Bling Ring and a Gates 50T to get more inset. This requires machining out the Gates 50T and machining off the Lekkie chain teeth, then heli-arcing them together. (ADDED: Don't know if a machined 46T matted to a machined 42T Lekkie Bling Ring can be made to clear?)

    Hope this helps if you go with a Bafang BBS02B, AKA “The-Silent-Reliable-Gaint” 750W/48V mid-drive motor that gives “you” total control over settings (I’d keep it stock as designed). IMHO the Bafang BBSHD has too fast of a cadence if you like to pedal; stick with the stock BBS02B with 48V battery. YMMV
    Last edited by Rider; 09-18-2018, 06:38 PM.
    MOVING BACK TO PEDAL...
    2020 Banshee Paradox V3 1x11 (pedal)
    2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

    Comment


      #5
      thank you! speaking of offsets, do you know what the crank offset is with a bbs02? I've read about people using different cranks or even the lekkie buzz bars to regain a centered pedal stroke.
      Intro, Belt Driven Build

      Comment


        #6
        I do not, but the Lekkie Buzz Bars for Bafang mid-drives have an 18mm(~0.7in) offset on the left arm that I believe is meant to center the pedals.

        They are crazy expensive when ordered from Australia (Over $150+ US):
        https://www.ebay.com/itm/Lekkie-Buzz...r=512271263156
        Last edited by Rider; 09-19-2018, 03:42 AM.
        MOVING BACK TO PEDAL...
        2020 Banshee Paradox V3 1x11 (pedal)
        2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

        Comment


          #7
          If I may, an update on the Rohloff - the older threaded chain sprockets have the 54.7 chain line (except for the 13 tooth).

          The new, splined chain sprockets use one of three carriers, spaced out at a 55mm, 57mm and 58mm chain line. Now, what happens if you put a belt sprocket in a 58mm carrier? I don't know, because I don't know if the belt sprocket is offset. If it does have some offset, and you set the offset "out", at least on my current Rohloff built it would clear the frame:
          Click image for larger version  Name:	20180919_121729.jpg Views:	1 Size:	73.8 KB ID:	74018



          The Rohloff gives you more fiddle-room (at an intense price, and arguably too many danged speeds).
          Last edited by ncmired; 09-19-2018, 09:27 AM.

          Comment


          • Rider
            Rider commented
            Editing a comment
            That's great news! The further out the chain/belt line the better. In fact, one might even be able to use a 39T on a BBS02B if it gets out there far enough to clear the reduction gear housing.

            If you can believe what you read (I don't own one yet), the new Rohloff electric shifter can do 3 gear jumps with one push. That is very useful and reduces the number of shifts from one end of the spectrum to the other. A Rohloff belt drive just got even easier to electrify with a BBS02B!

          #8
          Originally posted by Rider View Post
          I do not, but the Lekkie Buzz Bars for Bafang mid-drives have an 18mm(~0.7in) offset on the left arm that I believe is meant to center the pedals.

          They are crazy expensive when ordered from Australia (Over $150+ US):
          https://www.ebay.com/itm/Lekkie-Buzz...r=512271263156
          On my narrow bottom bracket (68-73mm) builds, at least so far the BBSHD pedal Q has been pretty even, as in less than 5mm variation side to side. The BBS02 - no such niceness, and seems to me to be a Bafang design oops, frankly.

          The Lekkie Buzz Bars can be had from U.S. vendors, slightly less painfully, for about $115 (been there, just did that).


          Comment


          • Rider
            Rider commented
            Editing a comment
            Simply buy a BBS02B in 100mm form and it all centers out from the start (pretty much anyway).

            With that said, I ride both of my BBS02B rides with stock Bafang crank arms and no offset adjustment without issue.
            Last edited by Rider; 09-20-2018, 04:22 PM.

          • Overkill
            Overkill commented
            Editing a comment
            thank you! i did find the buzz bars around that price. Rider that’s an interesting idea.

          #9
          On the charging issue, like Rider I was surprised to see that "unplug the battery from the bike" recommendation. I'm pretty sure I've seen it stated here that it's not a problem. Maybe it was found to be a safety problem, especially on the 52 volt batteries, and it's the rule now - dunno. I'd be very surprised many are following it.

          On the plug - standards anyone? I think one manufacturer (Juiced) is setting one for themselves (48 (barrel) versus 52 (XLR)). I'm half tempted to integrate the charger onto the bike - that way I could plug in, if 110VAC was available, anywhere.

          P.S. that picture you posted is gorgeous - almost missed it, since it's just a thumbnail in your post:

          Click image for larger version  Name:	fetch?photoid=73855.jpg Views:	1 Size:	2.23 MB ID:	74058

          Last edited by ncmired; 09-19-2018, 01:45 PM.

          Comment


          • paxtana
            paxtana commented
            Editing a comment
            The cutting mat is a nice touch. Having recently bought one I find it's almost like a cheat code for great pictures.
            Especially when the lines emphasize a narrow depth of field, really makes it pop.

          • Overkill
            Overkill commented
            Editing a comment
            hmm, maybe thats it! i'm a photographer and i never really think about why i like the things i shoot. but i do like this picture :)

          #10
          Thank you :) I just realized that i can include it at various sizes in the post, i'll make the next ones bigger!

          I asked Luna email support for clarification on the issue and they said that there is no risk. So the person I talked to at Luna phone support was probably just being overcautious.

          For the Rosenberger connector I tracked one down at Mouser. It cost $20 more than Luna was selling it for and is a straight plug rather than a right angle plug.


          Do you have an opinion on the necessity of on/off switches to gate the battery? I'd thought to put in the one Luna sells but its out of stock. Grin has a key switch that can handle 25A and is pretty inexpensive, and the display that i'm planning on running has its own power switch although that is later in the chain.

          I also read through your first build. I was going to wait until i had the front chainline in front of me to decide on the rear hub, but it seems that an alfine is out of the running. It looks like SA 3 speed for me since I'm keeping the belt :)
          Last edited by Overkill; 09-19-2018, 02:22 PM.
          Intro, Belt Driven Build

          Comment


          • Sebz
            Sebz commented
            Editing a comment
            Hi, I was the one that wrote the articles on charging. Yes we have to be careful and must follow safety guidelines. It's always better to be on the safe side considering that charging a battery is the most dangerous part of using Li-ion, we recommend charging in a fire safe place for that matter.. And since it's complicated to put the whole bike in a safe place, removing the battery is easier. That being said if you are monitoring the charge and the bike is outside or in a safe place I see no problem charging it connected to the controller. I do it all the time.

          • Overkill
            Overkill commented
            Editing a comment
            Thanks for the clarification Sebz!

          #11
          Originally posted by Overkill View Post
          I also read through your first build. I was going to wait until i had the front chainline in front of me to decide on the rear hub, but it seems that an alfine is out of the running.
          Can't remember if you said - which motor are you going with, BBS02 or BBSHD? The 68mm BB / BBS02 / Alfine or Nexus / Gate belt is doable (several have) - up to what tire width I don't know, but I'll guess up to approx 45mm. The math does not work with the BBSHD unless you carve the BB back, probably a good 8-10mm.

          I like the Alfine / Nexus 8-speeds, the Nexus in particular is a good bang for the buck. On the Shimano 8-speeds, the supposedly strongest 1:1 gear (5th) is about 2/3 out in the range. The rotary shift position on the drive side hurts it for our applications.

          I was drawn to the magical belt, but the need for the perfect alignment and the high cost of minor gearing changes (compared to chain) swayed me away, for now.
          Last edited by ncmired; 09-19-2018, 06:10 PM.

          Comment


          • ncmired
            ncmired commented
            Editing a comment
            Does the Nuvinci 380 make noise? I've never ridden one.

            Time to prepare a spreadsheet ...
            Last edited by ncmired; 09-20-2018, 08:28 AM.

          • Overkill
            Overkill commented
            Editing a comment
            I'm not sure. I love the idea of the nuvinci and it seems that a bbs02 won't overpower it and cause it to slip. It all comes down to chainline though!

          • ncmired
            ncmired commented
            Editing a comment
            I think the Nuvinci chain line is ~49mm, belt line ~45.5 (135mm O.L.N) - https://www.gazelle.nl/media/gene-cm...330_en_380.pdf

            The Nuvinci hubs have chain ring / sprocket ratio rules too, like the Rohloff. They're both cozying up to the mid motors - well, the Bosch for now, anyway.

            No major bike brand that I know of gives a shite about Bafang, which kinda worries me. Dare I speculate (dare, dare!) that Bafang's Ultra motor is DOA (good luck finding parts), and I also feel they're quite overdue on a BBS take 3 design. The Bafang Max integrated motor may be getting some acceptance (but not from Luna, it seems). Lightening, please don't strike me for such blasphemy!

            IMHO the Bafang BBS series is the only, sensible mid-drive available to us DIYers - at least for my purposes (commuting, errands, integrates fairly well, parts support, still a bicycle). I'm keeping some spares on the shelf - so, yes I've bought in.

            And, Luna has treated me very fairly - without them I wouldn't have ventured into the DIY e-bike world.
            Last edited by ncmired; 09-20-2018, 11:32 AM.

          #12
          "It looks like SA 3 speed for me since I'm keeping the belt :)"

          Yeah, that's kind of the point of buying a belt drive frame. They are nice. If you haven't bought your rear cog yet, I will let my 24T go if interested (PM sent).

          The black/blue or black/red will both look sweet on that beautiful frame. ;-) No grease, no rust, no dirt sticking to it; just hose off the dust and/or wipe it down.
          Last edited by Rider; 09-20-2018, 04:24 PM.
          MOVING BACK TO PEDAL...
          2020 Banshee Paradox V3 1x11 (pedal)
          2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

          Comment


          • Overkill
            Overkill commented
            Editing a comment
            Thanks I will keep it in mind! I was thinking about a 22 but was considering the 24 too. The 22 puts the middle gear right where my current single speed commuter bike is.. and that bike gets me everywhere but fast and sweaty and having to stand out of the saddle for hills. A 24 might take the edge off but so might 1300 Watts hahaha

            By the way Rider, on your SA 3 speed hub which gears click all the time? I’ve heard everything from only the easiest is silent to only the 1:1 is silent to eventually the clicking stops. I’d love to know what your experience was!

          • Rider
            Rider commented
            Editing a comment
            I had to go out and ride it while listening for clicking. Mine has no noise in 1st or 2nd and a slight slow paced click in 3rd that is hard to hear. Being a freewheel cassette 3spd, it does have the normal fast paced clicking when you freewheel coast.

            Oh, and 1300W will probably make corn kernels of just about any bicycle IGH over time... (just a heads up on going over the 750W zone)
            Last edited by Rider; 09-20-2018, 04:23 PM.

          • Overkill
            Overkill commented
            Editing a comment
            Thank you! Its very helpful to have the benefit of your experience!

          #13
          Originally posted by Rider View Post
          [No grease, no rust, no dirt sticking to it; just hose it off the dust and/or wipe it down.
          Oh, you just shoosh now ...

          Just kidding. BTW, did you know there are spring-type belt tensioners, seemingly now approved by Gates? Mostly for full suspension bikes, I'd guess. Like this pinion drive frame:
          Click image for larger version  Name:	DSC06325.jpg Views:	1 Size:	186.0 KB ID:	74073




          But, this would also permit belting bikes like that Trek frame with the high-mount chain stay.
          Last edited by ncmired; 09-20-2018, 11:37 AM.

          Comment


          • ncmired
            ncmired commented
            Editing a comment
            Calfee, that's what I thought too, and the Gates manual still says it's a no-no: https://www.gatescarbondrive.com/~/m...rive.pdf?la=en

            Gates also is quite particular about the static belt tension - how is it maintained with a pulley like the above, a calibrated spring?
            Last edited by ncmired; 09-21-2018, 08:20 AM.

          • ncmired
            ncmired commented
            Editing a comment
            Rider, yeah, the pinion drive is pretty sweet. I have had thoughts about learning a bit about hub motors, and toyed with purchasing a Priority 600 (one of the few, relatively inexpensive entry point pinion drive bikes) as a test stand.
            Last edited by ncmired; 09-21-2018, 08:11 AM.

          • max_volt
            max_volt commented
            Editing a comment
            The manual indicates do not back-bend or forward-bend when handling. Automotive timing belts are routinely going back and forth.

          #14
          I will throw this out there for a good strong IGH. I have a Sturmey-Archer heavy duty 5spd disc brake IGH on my Surly ECR (RX-RK5). It has held up very well over about 2,000 miles so far. They make a 26T Gates CDX belt drive cog for it (Part # CT1126AMNS), but the belt line is similar to all the over IGH’s that present issues getting the front inward to match it. The SA 5spd has 25% gear spacing between all the gears, giving a 270% range.

          ADDED: RX-RK5 chain line is 44.0mm with 1/8” flat, 42.3/45.7mm with 1/8”dished, 43.5/44.5mm with 3/32” flat, and 42.0/46.0mm with 3/32” dished sprockets. SA lists 17-20T & 24T sprockets, but the 24T is impossible to find (see my Surly ECR thread build for how to make a 25T custom rear sprocket).
          Last edited by Rider; 09-20-2018, 04:28 PM.
          MOVING BACK TO PEDAL...
          2020 Banshee Paradox V3 1x11 (pedal)
          2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

          Comment


            #15
            Overkill - I just reviewed your frame choice on Soma's site. Apparently the Riff replaces the B-Side with changes in tire width ability (up to 2.8") and the bottom is now 73mm, not 68mm. Those to changes are going to be your challenges, but I think you will be okay. The 73mm BB puts the BBS02B 2.5mm further to the right side. The 2.8" tire clearance increase likely pushes the chain stay over a bit too. Assuming the front Gates CDX belt ring pictured in your initial post is a 50T here is what I would recommend.

            Buy a "flat" on the inside 130BCD adaptor so you get a little bit more inward when mounting your belt ring. Slide the BBS02B into the bottom bracket with adaptor and ring mounted and see if the belt ring hits the chain stay (hopefully it won't) and you can test bolt the Bafang in place with a flush tight mount on the right side against the mid-drive motor. Measure your clearance from belt ring to the chain stay. This will be what you have to work with, if the belt line is too far out as mounted. If everything clears with this test fit, I think you will be okay as is at the rear with a SA CS-RK3.

            This is my logic:
            My adaptor is not flat on the inside mounting surface. It has a 1-2mm inset which moved the belt ring outward that much from where a flat adaptor would be. You save 1-2mm there, which counteracts part of the 2.5mm addition the 73mm BB on your bike has that mine didn't (2.5mm - 1-2mm = 0.5-1.5mm). I had a small spacer on the outside of the rear belt cog on the cassette, so there is a little room there too. Unfortunately there is no real way to tell until you slide a adaptor mounted 50T belt ring on a BBS02B into your BB to check it. If you know someone with an unmounted BBS02B and you have a flat 130BCD adaptor in hand, you can perform that test fit before even ordering a Bafang of your own.

            A millimeter is a really small amount (1mm = 0.03937"), so two millimeters is only 0.07874". For comparison, 1/16" = 0.0625" and 1/8" = 0.125" (3.175mm). So an 1/8" is MORE than 3mm.

            ADDED: One more check that can be done once the BBS02B, adaptor and belt ring is mounted to your frame (and everything clears) is to measure the exact belt line while mounted. Now subtract the distance from the belt ring to the chain stay from the known mounted belt line. If that number is less than any other IGH you might want to use, you can add spacers to the belt ring to move it inward if there is gear reduction clearance for them -OR- shave the right edge of the BB the amount needed to get everything in line with your chosen IGH. Some people don't want to shave their BB edge because it will require spacers there if they ever return it to a pedal application. My guess is there won't be enough gap between the belt ring and chain stay to get the belt line to 45-46mm anyway (check inner gear reduction housing to chain stay too, they both have to clear)

            As stated many times, the SA CS-RK3 and Rohloff are the only "easy" belt drive IGH applications I know of and the wider tires and wider BB's of the most modern bikes, plus their curved down tubes are making clean easy applications even harder than the old straight down tubes and 68mm BB's.

            I still have my eye on a Trek Stache or 1120 Rohloff belt drive build, but that's a longshot in both application (PF 90 or PF92 BB) and money. Although a pedal version of either one of those would be doable and a very sweet ride indeed (no E-assist though).
            Last edited by Rider; 09-20-2018, 06:35 PM.
            MOVING BACK TO PEDAL...
            2020 Banshee Paradox V3 1x11 (pedal)
            2018 Soma Wolverine 3spd IGH Belt Drive (pedal)

            Comment


            • Overkill
              Overkill commented
              Editing a comment
              Thank you! I read through your build thread all the way yesterday. It looked like you mounted the rear cog 2.5mm from its outermost position, so I was hoping that mounting it as far out as it would go would counteract the 2.5mm additional B.B. width on each side. Does some of that space need to be there for a lockring?

              My front is a 50t. Would a different size help here? As a side question, I noticed that you eventually went 55/24 which is very close to the 50/22 that I was planning to run. Was there a reason you increased the front rather than shrinking the back? I was going on the assumption that the smaller the front cog the better.

              I ordered my bbs02 and battery a couple of days ago. I’ll go get the frame prepped so I can test it out as soon as it arrives.

              I had ordered the same chainring adaptor as you a week or two back. Most of the ones I’ve found like this one:

              The California Ebike CNC machined chain ring adapter can be installed in place of the standard 46T chain ring supplied by Bafang.  These adapters fit the BBS02.  An adapter for the BBSHD is also available. Black Anodized CNC 6061 Aluminum BA130 This adapter will accommodate chainrings from 38T to 55T with a 130mm BCD.


              Have an inset on one side, but I bet I could flip it around to gain a little bit. I’m not opposed to facing a bit off the bottom bracket, but I suspect that width is there to support the wider tires.

              Here are some 0.6mm spacers I found. A couple of these might do the trick if i need to lose a ml off the front chainline. Man Origin 8 makes some good problem solvers. I wasn't familiar with that brand.

              Find many great new & used options and get the best deals for Origin8 Chainring Spacers SS 0.6mm SL Bgof20 at the best online prices at eBay! Free shipping for many products!


              I’m fine with the SA hub. I’d thought about some of the others but really 3 speeds is all I think I need considering my background singlespeeding. I'll keep a granny and an overdrive just in case, but I'd expect to spend most of my time in the middle gear. Its pretty flat here in Denver.

              Thanks for your continued assistance!
              Last edited by Overkill; 09-21-2018, 12:39 PM.
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