No announcement yet.

Decision to be made

  • Filter
  • Time
  • Show
Clear All
new posts

    Decision to be made

    New to e-bikes...fell in love with an Electra Super Moto 8i with 27.5" wheels....after discovering Luna...researched installing mid frame, nexus 8 speed hub.....nervous now.....wilI I destroy the bike? Can it handle the torque?
    Discovered Lunas All Terrain 500 ....out of stock but....has what I'm looking for. I am willing to wait...figure out how to purchase on limited funds.....what would you do?


    i would consider a BBSHD 750W version to save that hub. Some people run it 1500W and say its OK. But it's just a matter of tuning to change that and soften up the power application to suit yourself. BBS02 would work also.
    2 things to consider. The single speed chain is a big plus for strength, except they're fussy about the chainline and the Nexus shift casette pushes that in a bit. Probably a 42T inset chain ring will be needed. This chart will get you started on the rear chainline. Try to match it at the the front +/- 3mm.
    The other thing is the Nexus has several overdrive gears that no casette has. This could result in some long gearing especially with large 27.5 tires. There is a new Nexus E bike 5 speed hub and all the indirect gears are overdrive. They make some larger rear sprockets for them that may be needed to get a useful top gear, and low enough 1st gear for creeping around pedestrians. They have 24t,27t, and 30t options. They have 6 drive ears instaed of 3 that normal Nexus has. so some grinding may be required if you need to use them.
    Here is a gear calculator with the Nexus hub in it. Choose speed at 90RPM for "gear units", and your tire size and chainring. It can calculate several cogs at once.

    SG C7000 5D is the hub that has the larger cogs available. But I ran the gears and 19-21T x42T both look good.
    I would plan on adding larger brake rotors, and with no suspension fork a top speed of about 25-27mph. A suspension seat post is a common upgrade around here also.
    The upright riding position is good in traffic, and the tires are big enough to provide some suspension if you keep them below 30psi. Not a bad starting point for an electric cruiser.
    Last edited by Retrorockit; 05-16-2020, 08:52 PM.


    • HunterRoark
      HunterRoark commented
      Editing a comment
      Truly appreciate your detailed input. I am seriously considering purchasing a complete Luna All Terrain 500 e-bike instead.
      Thanks again,