Touring - Someone should make a gear reducer hub

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
Like an old VW Bus final drive. Get off the bike, flip a lever for flat mode or hills mode.
LarDasse74
10-02-08, 08:27 AM
Have you ever heard of a company called Sturmey-Archer? They have been making a product like this for, oh... almost 100 years. It's got a gear for the flats, a gear for the uphills, AND a gear for the downhills! You don't even need to get off the bike to actuate it!
staehpj1
10-02-08, 08:46 AM
Not a hub, but the Schlumpf Mountain Drive works kind of like that...
http://www.pbwbikes.com/product_info.php/products_id/59
LOL! That Sturmey Archer would mean three shifters on a bike. :) But it's good and inexpensive. That Schlumpf is pretty expensive but sure looks like it works.
Wyzard360
10-03-08, 04:25 PM
Isn't that the point of your regular gears?
BikeManDan
10-03-08, 05:54 PM
:wtf:
AbueloLoco
10-03-08, 06:21 PM
I have a SRAM dual drive on my bike friday with a 7 speed rear cassette and a three speed internal also in the hub. I don't know of a reason one couldn't put a double or triple chain ring on the front too. I am no techie, so there may be a reason not to. How much gearing one needs is another question altogether.
Isn't that the point of your regular gears?
Not enough when you have to drag a kid in a trailer plus both people's gear.
Booger1
10-03-08, 08:46 PM
That could be done with a planetary gear set in the rear hub without to much trouble.It would work like the old hand crack pencil sharpeners on the inside,same principle(remember those).Instead of a hand crank,the cluster would drive the sun gear.That would give you 27%-33%,up or down,depending on which way you ran it.It would triple(guessing)the weight and diameter of the hub.You would have to make it big enough to fit a sun gear and a set or two of orbiting gears.You wouldn't even need a cable,you could reach in the hub with an allen wrench and turn it 180 degrees to engage/disengage.I'd be surprised if someone didn't do some version of it already.
I've never seen the lever deal on VW reduction boxes but I know the made alpine gear sets for them.
Flip flop hub with different sized cogs?
cyqlist
10-04-08, 04:57 AM
LOL! That Sturmey Archer would mean three shifters on a bike. :)
Like this:
http://www.geocities.com/cyqlist/ssshifta.jpg
smovlov
10-04-08, 09:30 AM
http://sheldonbrown.org/otb.html
63 speeds. There is a description 3/4 of the way down.
I had the Shram dual drive on a recumbent. If it is anything like a Rohloff, it may have a minimum ratio or it gets overstressed, relative to a tripple up front.
I used to have this gizmo, it's still out there, where you mounted a 4th ring on the inside of the the tripple. You could pull a stump with it. Not sure whether it would work with modern shifters, but it was fine on friction. It's a mountain tripple thing.
This isn't the one I had, but it is a similar idea:
http://www.abundantadventures.com/mt_plus.html
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.