Building a better Tall Bike

Step 5 Align top triangle with bottom bike

Now get your seatpost into your bottom bike, just tight enough that it soesn't slip on it's own. Use a straight edge against the BB shell to line the assembly up with the bottom bike. clamp it tight, now eyeball it from different angles, look good? the seat tube of the top bike should be parrallel to the bottom one, the bottom brackets of the two should line up nice.