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Step 9 Freewheel (on rear wheel)

As you see, this wheel offers two options. On the right side is a fixed cog where a lock will be attached. The fixed cog does not move so that when the wheels are in motion, the cog must spin. The left side of the wheel has threading on the hub where a freewheel could be attached. A freewheel allows for coasting, which means that it does not need to rotate when the wheel is moving (and so you don't have to pedal while the bike is in motion). For multiple gears, a larger, multi-level freewheel is required for the chain to move back and forth on when gears change.

First, put on the sprocket as tight as possible going one direction with the tool gripping onto the teeth of the sprocket. Here I used a shop-made chain to go over the teeth of the freewheel. After that, put the lock on the freewheel going the opposite direction using a lock ring tool that fits around the ring to tighten it and keep the freewheel in place.

Comments

[Oblongata]

Just a little terminology update: A gear attached to the rear wheel that can not spin freely (can not free-wheel) is not a freewheel. It is a fixed cog. You also appear to be referring to the thread on the hub as a freewheel? Hubs with the ratcheting mechanism built into them are called freehubs, but this is not one of those. Any single cog (BMX style) or gear cluster that has the ratcheting mechanism built into it and threads onto one of these types of hubs is a freewheel. Cool bike though!

[Oblongata]

Excellent fix, terminology is now as good as I could ask for.