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View Full Version : Interesting Approach to Electric Assist

tuxbailey
03-21-2018, 10:10 AM
https://i.imgur.com/2a39gXE.jpg
camelopardalis
03-21-2018, 10:38 AM
I love the creativeness. And it looks like it might actually work.
Mark McM
03-21-2018, 11:41 AM
Since it apparently drives the cassette, it would literally be a pedal assist, since it would also drive the cranks/pedals.

Also, although there are multiple rear sprockets, I don't see a derailleur (nor any indication of a multi-speed hub), so this would presumably be single speed. And since the motor drives the pedals, when the motor was on it would behave like a fixed gear.

While creative, I'm not sure the idea has been fully thought through.
AngryScientist
03-21-2018, 11:46 AM
Since it apparently drives the cassette, it would literally be a pedal assist, since it would also drive the cranks/pedals.

Also, although there are multiple rear sprockets, I don't see a derailleur (nor any indication of a multi-speed hub), so this would presumably be single speed. And since the motor drives the pedals, when the motor was on it would behave like a fixed gear.

While creative, I'm not sure the idea has been fully thought through.

it could be that the large driven cog is on the hub as a fixed installation, and somehow a freewheel is attached after that, so the pedals would be independant of the driven cog?

hard to say from the picture...
Mark McM
03-21-2018, 12:09 PM
it could be that the large driven cog is on the hub as a fixed installation, and somehow a freewheel is attached after that, so the pedals would be independant of the driven cog?

hard to say from the picture...


Hmmm... It's hard to say from the picture, but I suppose what you say is possible. If it uses a freewheel instead of a freehub (and based on the rest of the frame it could be of that vintage), then it's possible that the large sprocket is screwed onto the hub behind the freewheel. But I suspect that's not the case: There are a total of 5 sprockets, and freewheels with less than 5 sprockets are not common (at least not in the last 70 years).

Since there is no derailleur hanger, and because the bike has a chain guard (not common on derailleur bikes), I suspect that the bike started out as an internally geared bike (thus the cable stop on the chainstay), but the freewheel wheel substituted in as the cheapest and easiest way to get multiple sprockets.
tuxbailey
03-21-2018, 12:10 PM
Since it apparently drives the cassette, it would literally be a pedal assist, since it would also drive the cranks/pedals.

Also, although there are multiple rear sprockets, I don't see a derailleur (nor any indication of a multi-speed hub), so this would presumably be single speed. And since the motor drives the pedals, when the motor was on it would behave like a fixed gear.

While creative, I'm not sure the idea has been fully thought through.

I would say more like a guy gathering whatever parts available to make it work. Probably saving some effort while cruising, not likely enough for climbing.
Mark McM
03-21-2018, 12:24 PM
I would say more like a guy gathering whatever parts available to make it work. Probably saving some effort while cruising, not likely enough for climbing.

Yeah. Probably whomever did this had little to do one Saturday afternoon, went down to the garage and saw his old bike and his portable drill, and thought, "hmmmm ... I wonder ...". I've produced many projects (often not nearly as successfully) the same way.