Bespoke ordered bike at about $3K+ from Bike Friday,* Hill Climbing? add a Mid drive motor ..

the 7 or 8 by 3, the S-A combination of Internal Gear hub, the 3, and a cassette for the 7 or 8
will make up for motor having just one chainring..

In general, Wheel Hub motors do not have hill climbing torque..

* most folding bikes make a single size product, regardless of the size of the rider .... you just adapt..
only Bike Friday builds to the customer's size..

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My LBS here, has done conversions of mostly MTB, with mid drive motor kits, to existing bikes ...
the kit, installed , is $1600..








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