Just a thought Nuvinchi hubs

Goat Herder · #1 01-05-2009, 03:56 AM

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Clotho · #2 01-05-2009, 08:07 AM

The Nuvinci has a pretty wide range already. If you should ever feel the need for more you could always use a dual sprocket freewheel like this one at the bottom of the page. DOS Freewheel you wouldn't even need a deraileur.

jasonh · #3 01-05-2009, 09:25 AM

While we're talking about the NuVinci, I noticed they will be selling a "developers kit" for light electric vehicles for $600. Has the regular hub, plus an electronic shift controller - which means an "auto" trans and wouldn't get the authorities so uppity. Thought it would be a cool idea for a bike...

Fallbrook Technologies

Clotho · #4 01-06-2009, 10:50 PM

Thank you for linking that. Very cool technology.

**Dan** · #5 01-08-2009, 02:00 AM

Awesome idea Goat Herder! With a reducing jack shaft, 2 chains (like some electrics) and freewheeling cranks,would be an internal shift. Just woke thinking about your idea. Could easily be done and would work great. Would need a chain guard (round, flat plastic sheet) between the largest rear bike sprocket to isolate the engine chain but would work.

This could be a winner!

happyvalley · #6 01-08-2009, 08:17 AM

Anyone ever look into the power loss factor with NuVinci?

This is from an Ebike site where 30% power loss is presumed:
Endless-sphere.com • View topic - Using the NuVinci hub on my e-bike

**Dan** · #7 01-08-2009, 08:49 AM

with an electric 30% would be an incredible loss. With gearing on a ICE would it be as great a concern? And not worth the return...

Asking

happyvalley · #8 01-08-2009, 09:57 AM

Since my motor of choice is 1.6HP I would be losing a third.....down to about one horse.
Fairly significant.

This is presuming, of course, the Ebike guy on that link has it right at 30% loss.
Comprehensive dyno test would be the only true evaluative measure, but that's why I asked.

Aside from the cost, which comparatively speaking is more than something like the Nexus but far less than the Rohloff, there is the weight factor.
For me, this is a real trade off on the NuVinci coming in at around 9 lbs.

jasonh · #9 01-08-2009, 10:58 AM

If you read NuVinci's whitepaper on use for electric vehicles, I seriously doubt you have a real loss there. Increased top speed, increased range, increased hill-climbing ability, increased acceleration...doesn't sound like a loss to me.

http://www.fallbrooktech.com/LEV-CVT_Whitepaper.pdf

happyvalley · #10 01-08-2009, 12:17 PM

Yes, I have seen the Fallbrook tech literature but considering it comes from their internal engineering dept. I would hardly expect anything different.
That's why I asked about either anecdotal or better yet empirical evidence. The Ebike
site I linked is one of the few conversations on this I've encountered.
On another motored bike forum, a well informed user when asked about the NV confirmed a fairly substantial power loss, in his estimate 25%. He seemed content to live with that however,
explaining his setup is primarily useful in low end torque in the off road riding he does and he
is running a fairly powerful motor.