Ellsworth gearbox bike?

[dazz]

With all the talk, hype, proto's & photo's flying around the last few days, I was wondering if anyone on here can tell me what progress Ellsworth have made in building a bike using the NuVinci hub? I'd like to find out more, as Fallbrook seem to have a lot of promises & not much to show for it.

The deal is talked about here:
http://www.bicycleretailer.com/bicycleretailer/search/article_display.jsp?vnu_content_id=1002117752

The design of the hub is shown here:
http://www.fallbrooktech.com/02_Demo.asp

[Red Rocket]

Hmmmm. That NuVinci hub is a great design in terms of simplicity. I heard something about it being not all that great for stuff like donwhill (yet) because of the large fluctuation in torque loads we can put out. I can't find any evidence to support this claim though, it was just part of a discussion on ridemonkey I was looking at.

Can't help you with the ellsworth information though.

This post is kind of irrelevant.

[bazza]

Hmmmm. That NuVinci hub is a great design in terms of simplicity. I heard something about it being not all that great for stuff like donwhill (yet) because of the large fluctuation in torque loads we can put out. I can't find any evidence to support this claim though, it was just part of a discussion on ridemonkey I was looking at.

Can't help you with the ellsworth information though.

This post is kind of irrelevant.

is there a major difference in loads from mounting an internal hub in the frame or running it as a hub. im interested to know this. or even are different sorts of loads put on it? anyone technically minded should be able to fill in my very anti technical mind ahah.

[Refreshinglygood]

I'd love to have an internal type mechanism, for our sport they are the go (at least in my opinion) as long as the seals are good, we would be able to have a service interval and thats about it.

Problem I see is going to be weight.

[thecat]

Mounting it in the hub means that all the weight is a) at the rear b)in the wheel you are trying to accelerate and c) unsprung

Having the hub mounted in the frame gets the weight 1) centred 2)away from the parts affected by angular motion 3)Profit.... I mean, supported by the springs in the suspension which works to counteract some of the weight.

[thecat]

I'd love to have an internal type mechanism, for our sport they are the go (at least in my opinion) as long as the seals are good, we would be able to have a service interval and thats about it.

Problem I see is going to be weight.

The rolhoff type hubs use a planetary gear system.

A mate of mine has been running one for years in his Xc wheel. By the time you removed the deraileur, chainrings and sprockets the weight wasn't that much different from a standard set up. In 15 000km he has changed the 40mm of oil once. and that's it. No chable chages, no adjustments, no bit replacements.

Internal gear boxes have so many advantages that far outweigh weight conserns, If the can be done right and for the right price. If.

[alpinestar12]

Mounting it in the hub means that all the weight is a) at the rear b)in the wheel you are trying to accelerate and c) unsprung

Having the hub mounted in the frame gets the weight 1) centred 2)away from the parts affected by angular motion 3)Profit.... I mean, supported by the springs in the suspension which works to counteract some of the weight.

if the hub is in the centre of the wheel it dosen't matter that much as the mass is close (reletively) to the axle. but yeah, the sprung and centered mass points are good points...

[Refreshinglygood]

Cost is the other issue.