Building a better Tall Bike

Step 8 Set up drive train

now if you just want to do one gear, you can just make up a big long chain and run it from the top BB to the back wheel, using the derailleur as a tensioner,

If you're keeping the gears, you'll want to set up th drive train before finishing the seat stays,

Make up your top bottom bracket, and put on of the pair of drive cranks on the left side. pull the non drive crank from the bottom bike, and replace it with the other drive crank. make up a chain long enough for to reach, then adust the seatpost to tension the chain. while adusting chain tension you'll probably knock the alignment off, ust get it back as well as you can.