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18650 vs 21700 battery packs.

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    That pretty much what I have found with my pack that is in the 20ah range. I don't think I have ever killed it where the 12 ish ones I could and a few times did kill em. With the 20 the ah stands for ass hours and my ass isn't rated to spend that much time on the seat at one time so that becomes my range limit.


    • Retrorockit
      Giga Member
      Retrorockit commented
      Editing a comment
      This thing is 24Ah and yes it will wear your ass out! It's supposed to get better after a few charges.
      1- I love this battery. It can feed a BBSHD. Full throttle at the end of a long ride and no low Voltage cuttoff. Perfect!
      Low Voltage cutout in South Florida traffic cam have consequences.
      2- The bracket is a PITA. mid level fabrication skills required. You don't have to be a machinist, but it wouldn't hurt.
      There are probably very few bicycles this bracket will just bolt up to.If you don't have the skill, parts, and tools, pay someone who does.
      The hose clamp option is available. But Bolt On=Bolt Off with that option
      3- The lock is different.Needs to be manually locked to the bike every time.
      Scores- Performance 10, Value 10, Bracket 3, Lock 6

    I pulled the bracket off and took some photos but they"re stuck in my phone. My computer can't find them.
    I'm going to try and describe this mess.
    The metal parts (2) of the bracket are about 2 inches away from each other and only connected by plastic and 3 tiny machine screws that hold the wiring cover on. Structurally disconnected.
    The front bracket is about 4" long with 2-1" slotted long holes. This is the structural part of the bracket that engages the tabs on the battery. You will want 2x bolts here to hold the 14# battery.
    It can only use 5M button head bolts. This will not line up with any normal bottle mounts. It will be up towards the front corner of the frame.
    I was lucky. My 26" comfort bike has an 8" long head tube. Barely enough room to get the job done with normal size drill bits and an angle head drill. Most of you will have to be prepared to install 2x bottle mounts in a very tight space. Probably the size of the battery in most cases.
    The rear bracket will probably line up with one or maybe both holes. But the battery just sits on top of this. One bolt is probably enough here. Due to the plastic cover you can't see all 4 holes at once. It's like 2 separate projects that have to align perfectly when you're done. The battery plug sticks down in between the 2 brackets.
    If theft isn't an issue hose clamps are an option. But the flexible bracket may have issues with that also. It really needs the bike frame to align it.
    My advice is- get some 1'x2" oak or poplar trim and on the work bench-
    1- Make a straight line down the middle so all your holes will line up. You can put masking tape on the board and mark that if you want to.
    2-Drill, on a drill press if at all possible, 2-13/64" holes to match the bottle holes on the frame so you can bolt it to the bike and use it as a drill guide. Counter bore the holes so it sits flat on the frame. If this is difficult for you STOP RIGHT NOW! if you can't get this right in one try, don't go near the bike with a drill. It's a skill and it takes time to learn this. Drilling a hole in wood on a workbench is a lot easier than doing it on a round metal tube inside a bicycle frame. Quit while you're ahead.
    3- Find out where the rear bracket will sit on the frame and mark where the bolt hole is in the slot so you can repeat it on the wood.
    4- Put the bracket(s) on the wood in relation to the existing holes, and mark where the added holes will go. Further in from the end means more room for drilling holes inside of the frame. It also lets you put both bolts in that slot if you need to.
    5- Get your special tools together
    Short length 19/64" drill bit ( McMaster carr, Grainger etc.)
    Short length 1/4" drill bit
    Angle head drill, or 90* drill adapter
    Several steel Rivnut water bottle mounts.
    Rivnut installer tool. This can be done using a bolt and washer with pliers keeping the Rivnut from turning. If you can borrow one, do it. Or have a bike shop do this last step.
    A cheap set of transfer punches. These look like set of drill bits with a point on the end. Chinese ones don't cost much.You will need to cut one down because they're all full length. or an automatic center punch because you wont have room for a hammer in there.
    6- Mark all your holes on the center line of the board, working from whatever hole lined up, and the correct position of the bolt in that slot. You don't really need the 2nd hole in the rear bracket.
    7- Drill the holes you marked to 1/8". A drill press would be ideal. But you can turn the board over so the holes will get drilled into the frame through the marks. Bolt the board to the bike and using the 1/8" transfer punch mark the center of the holes. This is to keep the drill bit from wandering on the round tube. You can make the center punch bigger with a automatic punch to be sure the drill starts
    8- This is the point of no return. if you want to test fit the bracket and battery on the one bolt hole and see if the punch marks line up, do it now. See if you can get a drill and bit inside the frame to make the 19/64" holes where you need to. If you have to, put both bolts in one slot.
    9- Drill some 1/8" starter holes into the frame through the board mounted to the bike.
    10- Remove the board and drill the new holes in the wood to 1/4". Repeat step 9. 3/16" etc.Then 19/64". repeat step 9.
    11- install the Rivnuts. The special tool pulls straight up on the nuts to crimp them inside the frame. If you use a bolt to draw them up, they will want to tun until they grab. The pliers leave marks.
    It;s up to you which way to go. Any bike shop should have the tool.
    When you install the bracket the unused water bottle hole will cause it to not sit flat. Tap over the hole so it makes a mark on the bracket, and drill a clearance hole there. Or file it flat if you never want to use it again.

    With a one piece bracket and 3 long slots in it, you would just stick it on the bike, transfer punch the holes and get on with it. Probably 2 holes would line up anyway. Adding a 3rd would be easy.
    I did this freehand. I've been doing this sort of thing for many years. I don't recommend it in this case. I'll say "I got away with it" this time.
    Giga Member
    Last edited by Retrorockit; 4 days ago.


      You can get a look at the bracket in the Haiong manual here.
      The front plate which is loose has to be all the way forward when installed. In one photo it has slipped back. This will give you some idea of all the places it doesn't have mounting holes.



        Here is a drawing of it showing the 2-23mm slots for mounting bolts at the front end. There are slots under the plastic cover But the 50mm plastic section is all that connects it to the front where the battery is supported. When you open the cover the whole front bracket comes off with it. making it a separate operation to mount the back part. The 3 tiny screws on the cover are all that hold the 2 parts together.
        Giga Member
        Last edited by Retrorockit; 3 days ago.


          I finally found out what it takes to pull this battery down to 25%.. My long ride to an LBS 2 cities away about 36 miles out and back (I don't actually measure this stuff.) On the way back I had dinner, and then looped back about 1/2 of the trip to add some miles. I was trying to run the battery down so no effort to conserve Watts. Lots of 600W assist, and occasional bursts of full power. About 8 miles from home it got down to the 25% bar. When I got closer to home I tested 600W assist for 1/2 mile, no problems, and at on my own street I did a few full throttle runs. I still haven't managed to provoke a low Voltage shutdown on this thing. So at 25% level this thing has some useful range and power left in it. The 2A. charger it came with does take longer to charge this thing back up. My old battery was always charged over night. This one is taking a bit longer. So an upgraded charger would make sense of you're going to use the full capacity of this very often.
          So this battery lets me use the power of my BBSHD without worrying about range. 48V. vs. 52V. option you lose 15% range. I'm very pleased with the 21700 battery
          The design of the bracket is unfortunate..
          Giga Member
          Last edited by Retrorockit; 2 days ago.


            For comparison look at the bracket on the same brand 18650 pack of similar size. 4 slots end to end and the connector at the back end.