Re: Nu-Vinci Hubs? Anyone have any experience?

On Aug 12, 9:30 am, !Jones <h...@xxxxxxxxx> wrote:
On Sat, 9 Aug 2008 20:43:20 -0700 (PDT), in rec.bicycles.tech

"mike.a.sch...@xxxxxxxxx" <mike.a.sch...@xxxxxxxxx> wrote:
I have a Rans V2 Formulae HD26 with Xtracycle.com and NuVinci hub.
Great to just twist the grip after a rush stop and get to the lowest
ratio. It goes from 1/2 under drive to 1.5 overdrive.  I do not find
that it has the excessive drag that a Sram 3*7 internal gear does when
not in direct drive.  Although it says you can shift at any time, I
found that it holds the gear until you hit the top of the stroke, when
you are not able to push down on either pedal with platform shoes.  If
you are used to pedaling the entire circle with clipless shoes, you
won't notice this.  You don't have the definite steps of standard
gears.

OK, so direct is *not* at one end(?)!  With standard hub systems (my
personal favorite is a Bendix "red band", but it's a niche thing), one
gear is direct drive or 1:1... herein is the best efficiency.  Did you
notice that there was any difference?

The reason I ask is that I'm considering a Lightfoot Trike for a
handicapped adult and these also have front & rear derailleurs... or
two sets of rear cogs.  If there's no advantage, then my rider would
only use the NuVinci and I'd just lock the others in place and remove
the shifters... why confuse her?

Thank you, Chalo, for the link and Mr. Webber for your comments.

Jones

With the SRAM 3 * 7 (3 internal, 7 derailer), the middle gear was
direct and without loss. The underdrive and overdrive gear did have a
bit of a drag. When in underdrive, as soon as I had enough speed to
get to the middle drive, I would, then I would get more speed from
reduced drag. When I topped out the derailer gears, I would switch to
overdrive, and the reduced cadence and increased drag would quickly
induce me back to the direct gear.

With the NuVinci, there is a 1:1 ratio, but I cannot tell from a
reduced drag point. As I increase speed, I gear up as needed as go
right by the 1:1 point without noticing a low drag spot.
.

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