Another generation of the drive components. We designed them to be functional yet as simple as possible so that we can machine them all by next Tuesday and then get on to other things in this wild ride. We've got some good progress already - someone on our team served up a cafeteria tray of a few of the components the other day.
Bottom Bracket
Just like before, we are still designing the drive to go inside of a hollow frame. So on this here bottom bracket, we are centering the chainring on the spindle. Note the flat areas on the spindle to key with the spider and thereby prevent slippage.
A guide to the parts:
- Red = outer plates
- Green = frame inserts (embedded in carbon fiber frame)
- Yellow = bearings
- Gray = spindle
- Purple = spider
- Black = chainring
Transfer Gear
We are using an internally-geared 3-speed hub as a transmission. It will have two chains - one input and one output, similar to the chains on a tandem. Here is a system for adjusting the dropout angle so that we can tension both chains with one adjustment.Rear Hub
The rear hub is designed so that the rider can remove the wheel from the side - without messing with the chain. The rear axle fits into the hub, and the axle rotates with the wheel.
Here's a closeup on the spider, which is basically a modified split collar. It's going to be a small but action-packed machining job.
Front Hub
We've yet to detail it fully, but we're going to be modifying an existing Shimano Nexave roller brake. The brake engages with the hub from the side, so it will be fairly simple to modify it to fit on a one-sided fork. Here's an exploded view drawing from Shimano.