Two pulleys have to be put in place and one has to be a double. Only they don’t make doubles so I have to put one together from parts. The joy of this bike-build!
In the photo above I have a bolt resting in the pedal hole only to hold the slack chain up where a pulley has to go. This chain will not pull the chainring around, it is merely returning but has to hit the chainring right or it will come off the teeth. Therefore the need for the pulley to line it up right. The returning chain will not be aimed at the chainring after it leaves the gearbox because it has to be pulled away to missing the power chain – the horizontal one in the photo.
This photo shows one pulley in position to let the pulling chain move free of the returning chain. There will be two pulleys next to each other at this point, keeping the chain from coming off the cog on the gearbox.
Hopefully, with the slack taken up by all he pulleys, the chains will miss each other like in the photo above. This is never going to work, I can feel it in me bones!