Why build your bike?

Step 7 Bottom bracket, crank arms and chainring

Get a sealed bracket to last longer and without the need for upkeep, with no need to clean dirt and dust that gets into unsealed brackets and may grind the bearings. Grease the bottom bracket and bike case, place bracket in chamber and tighten. Here you will use a bottom bracket ratchet that can be found in a bike shop.
Put one crank arm onto the chainring, greasing each individual screw. Tighten with an allen key.
6b. Place arms on slightly lubed bracket and tighten hard. Here I used a hexagon shaped ratchet and a wrench on the other end to get the crank arms on.