I wonder if it would be possible to build one of these into a crank motor

[GaRRy]

Pinion 18 speed Gearbox - Eurobike 2011 - Pinkbike

http://www.pinkbike.com/news/Pinion-gearbox-first-ride-2011.html
saw a article about this while waiting a Physio

Seems to me one of these combined with a crank motor e.g. Bosche would take some beating. By combined I mean built as a single unit

 

[eddieo]

when I looked at it I though inefficient......not technical so I dont know really, cant see it working with a crank drive. maybe with a front or rear hub I would think...

 

[flecc]

Present crank drive units already have a size problem in both width and length, so it wouldn't be very practical to add this into the design.

It will probably be as efficient as a present day hub gear, but much less efficient than a derailleur.

 

[GaRRy]

Present crank drive units already have a size problem in both width and length, so it wouldn't be very practical to add this into the design.

It will probably be as efficient as a present day hub gear, but much less efficient than a derailleur.

They are claiming its as good as a derailer. Mind you at the price it is it should be. Read a few reviews and other than weight it does seem to be liked. Doesnt look like its that big in itself so doubt it would add much to the size. Maybe one to watch for the future but until price comes down cant see it getting that popular.

 

[flecc]

They are claiming its as good as a derailer.

Claims are too often bunkum Garry. The bike will still have a chain and sprocket drive, and a derailleur isn't a gear system, it's just a choice of different ratio chain drives. Therefore the comparison is with the derailleur having almost zero loss additional to the chain drive, with this having all the usual inefficiencies of toothed gears added to the chain drive loss.

In other words, not even remotely near to derailleur efficiency.

As said, I think it will roughly match the newest generation of hub gears like the Shimano 8 gear ones, but they are well over 10% less efficient than derailleur transmission.

 

[Ajax]

..then there's always future tech,
just around the corner waiting for new investors.

Team Clonc - YouTube

Automatic Bicycle Transmission (IVT) - YouTube

 

[flecc]

Still waiting for a proper explanation of that one Ajax, rather than his vague commentary which I heard some while ago. It appears to have a slipping drive since it's able to stand still on the output while with an input. In cars we call it clutch-slip!

 

[GaRRy]

In other words, not even remotely near to derailleur efficiency.

As said, I think it will roughly match the newest generation of hub gears like the Shimano 8 gear ones, but they are well over 10% less efficient than derailleur transmission.

Ok I will take your word for it 'v' the derailleur. But it still seems to have some real advantages over hub gears. (Weight moved to better location, easier rear wheel removal etc). I guess time will tell.

 

[Miles]

Seems to me one of these combined with a crank motor..........would take some beating. By combined I mean built as a single unit

They are doing it themselves: http://pinion.eu/en/discover-pinion/pinion-e1-8/

Miles

 

[GaRRy]

They are doing it themselves: http://pinion.eu/en/discover-pinion/pinion-e1-8/

Miles

Interesting. Based on price of gearbox wonder how much this costs

more info here

Pinion Drive System = Ebike Porn | ELECTRICBIKE.COM

current bike available with Bosch motor 4999 euros frame only !!!
http://www.nicolai.net/158-1-ION+20+E-BOXX.html#tab

and some more info
http://www.electricbike.com/nicolai/

 

[Mussels]

I like the idea of that but a couple of things come to mind...
1. If the motor is before the gears then it's pretty much the same as a standard crank drive through a rear hub, here the power the hub can cope with is an issue.
2. If the motor is after the gears then stress on the gears won't be an issue but it will be just like having a hub motor on a standard bike.
I like it but apart from being bling I don't see any technical innovation there to justify the huge price.

 

[flecc]

Certainly it's a better place for the gears that in the rear wheel hub, but what a big lump! As I remarked earlier, crank units are already a bit too big in some respects and this makes them even bigger by adding to the third dimension. The motorcycle-like frames in Garry's links seem very appropriate to the bulk and weight.
.