Attached is an option to route the chain. I want to have a geared hub in the middle to use as a transmission. This will allow for several gear ratios and help keep things simpler around the pedal sprocket. The pedal chain, left chain, would change levels with a idle sprocket, then run to the the geared hub, call it a mid drive, to the point where the rear suspension pivots. This should keep the rear suspension from tightening at pedal start up before any forward movement takes place, at least lesson the movement. A final chain will complete the power transfer to the rear tire sprocket. This is not drawn to scale and is just representative of the idea.
Looks very similar to the drivetrain on the Versatile. I think it uses a Rohloff hub at the intermediate point before going to the rear wheel. I know on the 26" Quest the chainline crosses right at or just below the pivot point for the rear suspension arm. I don't get any squat while accelerating.
ReplyDeleteAnother benefit of doing a mid-drive setup like that (or like in the Mango or early 20" Quests) is that you can easily step the gearing up or down, depending if you're looking for really high or really low gears.
The Rohloff hubs are a bit on the pricy side, but would be awesome to have. I am trying to keep cost down and appropriate fund accordingly. I will probably try a Sturmey Archer hub first. I really like the idea of being able to shift gears while being stationary. I am trying to partially follow the kiss (keep it simple stupid) rule.
ReplyDeleteGetting the velomobile going and showing it's buildable and practical is important to me.