[Knufire]

Originally Posted by Munchskull

Could some one explain how you get the chain in the tub. To me it seems like it would be a complex process.

Originally Posted by Brendan Browne

Sprocket layout:
Back wheel = Sprocket 1A
Center assemble= Sprocket 1B & 2B
Front wheel= Sprocket 2A
Chains were slightly loose which allowed for easy line up (once its in there the chains rub on the top/bottom wall but they can't go anywhere.
Spacers were round OD so the only hex profile you needed to worry about was lining up the hex axle and hex sprockets. Super glue only held the sprockets in for assembly.

Step 1: Cut Chains to length and assemble the loops (no master link)

Step 2: Super Glue spacers to sprockets creating your internal assembly (118 uses double sprockets with build in extrusions on the side for a single assembly) Double sprockets were not glued together.

Step 3: Press bearings into tube

Step 4: Put sprocket 1A on your back chain and drop through the end of the tube. Used a magnet to help slide the assembly down the tube. Spacers were undersized so it was easier to drop between the edges of the bearings. Used long small screwdrivers to help line it up. Once in line, axle gets put through.

Step 5: Using a machined pocket above the middle assembly, drop the first half of the sprocket assembly into the middle (pairing with the chain you just put in). Throw an axle/rod through to hold the 1B for the next step.

Step 6: Repeat step 4 but this time using sprocket 2A and the second chain.

Step 7: Drop sprocket 2B into the center assembly and slide the axle through both gears.

Now all 4 sprockets, 3 axles, and 2 chains are assembled. Move on to mounting the gearbox and wheel assemblies.

tl;dr, it's not easy.