The chainless bicycle.

[red750]

[old man emu]

This was a promoted as a start up a few years ago. The price quoted was $US3800. Considering the design and materials, and comparing it to a competition road bike, that price would seem OK. 

 

The arguments against it seem to revolve around the mechanical efficiency of rotating pedals -v- up/down motion. I suppose that argument is the same one that is trotted out when a new design is compared to a tried and true one.

 

I wonder if you can stop "pedalling" and coast if you want to.

[Yenn]

All it is doing is using only a small portion of the rotational angle of the pedals. There is still exactly the same transfer of vertical movement of the foot to circular movement of the wheel, except that in effect you have the equivalent of two chainwheels.

[onetrack]

The problem I see with the design is the gearbox design. Nothing in the inventors website tells us anything about how robust the gearbox is. That's where the greatest weakness lies.

 

As far as the design goes, it does appear to have advantages over the old chain drive bikes.

 

The second problem seems to be, the inventor is having trouble getting the bike into the market. I suspect there are still "bugs" in the design, and I suspect they might be in the gearbox. The video shows a rider coasting, so it obviously has coasting ability.

Edited November 9, 2020 by onetrack

[nomadpete]

The use of a lever at the hub will lose effectiveness.

Maybe a pair of rack and pinion drives to the hubs would provide linear power transfer.

 

Edited November 9, 2020 by nomadpete

[onetrack]

It's only got 4 gear speeds, too, I see. My current chain-driven bike has 24 gears, and I think having only 4 cogs would be a real drawback.

[old man emu]

Ahh! Remember the days when you were King of the Kids if you had a free-wheeling rear sprocket? Until that spoiled kid up the road turned up on his Malvern Star with 3-speed Sturmey Archer hub gears.

[Yenn]

I had one of those Sturmey Archer 3 speeds, with a built in dynamo. The best part was the dynamo. The gears were nowhere near as good as a derailleur. I must admit they were much stronger than you would expect.

It should be possible to change gear ratios, by varying the lengths of the levers on the new bike.

Edited November 10, 2020 by Yenn
Enlarging on theme

[Bruce Tuncks]

I remember the dynamo being on the front wheel. I too had a Sturmy Archer 3 speed, but mine was old to start with.

My current bike has electric assist and 6 Shimano  gears, but the gear ratios are so wrong that only the top gear is useful, even when going uphill. I need to try and get a bigger front sprocket.

Edited November 12, 2020 by Bruce Tuncks

[Dax]

Would like to have a go on one of these things, there is a huge loss with circular pedalling, but it gives your legs a bit of time to recover from the short downward stroke. Love my mountain Ebike and remember my first bike which was a piece of junk with the rear hub brake, never able to afford a Malvern Star but my second bike had 3 gears and hand brakes, that kept me mobile for a few years. Especially when got hold of a dynamo, then night riding was possible and could go anywhere, with a carrier on the back with two old leather school bags each side and basket on the front, it was like a home on wheels to me.