Monday, November 14, 2016

MTB to Electric CargoBike:

                                                                more room for a big motor
full suspension longtail cargo bike in video

Converting a mountain bike to a electric road bike, is not has hard as you might think. Hub motors climb hills with cargo much better when built into a 20” wheel. And they need suspenstion.

  • Steel Suspension MTB frame made for 24”-26” wheels. Make sure that it takes a disc brake in the rear.
  • Longer spring loaded oil shock to push the drive axle down about 3 inches. But you may not even need as much road clearance for the pedals as on the MTB. And you could to get 155mm cranks arms.
  • Fork for 20” wheels. It may need a longer head tube extension welded on.
  • 16” x 2.25-2.5” (21” o.d.) 4-ply Scooter tires will fit on a 1.25” bicycle rim.
  • Wide bicycle fenders are a maximum of 2.25” wide for 26” tires. They bend easy with only a little heat.

I put a 19” (23”o.d.) x 2” wide moped tire on a 19”motorcycle rim for my MTB-cycletruck frame made for 24” tires. So a 17” x 2.5” tire would probably fit fine with out lowering the crank too much. Measure the clearance for a 2.75” wide tire.

Do not put a larger diameter tire in front than the rear unless you can keep the steer angle the same. If the trail increases with out more rake, it will cause steering problems (wheel flop).

20" wheels on mtb frame?

Full Suspension Longtail 2.0

Build a new wheel and frame extention before spending money on mid-drive kit. And a longer axle to make room for a sprocket adapter on the brake side.

it can be very hard to find a frame
that will fit a 20" wheel

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