Need help with my first wheel build - for 20 inch fat DD rear hub

[MxusMick]

I have a 20" mag wheel DD hub on the rear, with a 26" front wheel, it works great! Better torque, better feel, though the pedals are lower and the brakes are off place. There are controller brakes to get around that, I say get the mag motor, reinforce the puncture proofing, and get on the road, too many complications can prevent the pleasure of electric cycle mania.