Thread started by BillyB at 06.19.07 - 4:26 pm

Did you ever have a 3 speed? It was pretty simple wasn't it?

Better than a single speed, but far less complicated and more reliable than deraileur bikes.

I like my fixed gear as it's very low maintenance, but when I go for a long ride, I always take my road bike that has 18 possible gear combinations. That skinny chain on the road is a pain in the arse though as you're always worried about cleaning/lubing and checking it for stretch.

So I'm looking at one of these:

http://sheldonbrown.com/harris/shimano-nexus.html#8

Here's some more info:
http://en.wikipedia.org/wiki/Hub_gear

Has anyone tried any of the newer 7 to 14 speed hub gears?

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I had a shimano nexus 7 speed on my whopper chopper and had no problems with it. granted I didn't ride that bike much. I would like another bike with one of these hubs.



cured1
06.19.07 - 4:38 pm

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My Dahon Speed TR foldie comes with a SRAM Dual Drive 24 which integrates a 3 speed hub with an 8 speed 11 to 32 T cassette. Don't have the teeth count on the single chainring up front but the resultant gear inches range on this bike with its 20" wheels is 21" to 114".

I like the Dual Drive transmission system a lot and would want something similar on a full size bike. The hub gear has wide ratio steps (73%/100%/136%) per click while the derailleur has closer ratios per click (haven't done the math, but it's easy enough to tell when riding).

I found I could upshift this hub under absolute full body power -- standing on the pedals -- and it doesn't gronch. Not so when downshifting the hub; I have to ease off a bit, as with a derailleur. So I've developed this street technique for accellerating of starting from a stop with the rear derailleur two clicks down from top gear and the hub in bottom gear. When the light turns green, I stand on the pedals like you guys on fixies and shift up the hub while accellerating until it tops out. Then relax a bit and click up the derailleur gradually through its two top clicks. I top out at about 20 MPH, having gotten there VERY quickly. Overspinning on a downhill I've gone up to 37.2 MPH on this little foldie, but not for long. Pretty surprising for such a little bike.

It'd really be sweet to have multiple chainrings up front with a Dual Drive on the back and full size wheels... somebody got something like 160+ gear inches that way...



OverTheHill
06.19.07 - 11:57 pm

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The Shimano Dual Drive system looks pretty cool. Coupling it with a 9 speed deraileur means that it still requires a narrow chain though.

They're ideal for folding bikes, as it eliminates the front deraileur.

The question for putting it on a traditional bike would be whether or not it improves shifting.

16 to 20 inch wheels are more efficient at speeds up to 18 MPH, so maybe some of the quick acceleration could be attributed to the wheels and not the drive train.

However - 8 gear ratios really doesn't cut it for long distance riding and the 14 gear rear hub is over $1,000, so maybe I'll have to compromise somewhere.



BillyB
06.20.07 - 9:58 am

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I've seen OvertheHill on his foldie... he can move... and climb. He made it up to the top of Topanga on that little guy... and blew past me on the way down.



digablesoul
06.20.07 - 9:18 pm

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