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View Full Version : Gears: derailleur and multispeed cassette in back with just one chainring in front?


Quentin
08-06-2008, 12:08 PM
Does anybody ride with a regular cassette and derailleur in back and only one chainring and no front derailleur? I've been thinking about setting up a bike like this, front derailleurs can be a bit sloppy sometimes so I was thinking of going without. If anybody rides this setup I'd be curious to hear how you like it.

lynnef
08-06-2008, 01:56 PM
I have a riding friend that did just that. She rode the 1000km Portland to Whitefish brevet with that very setup. It had a downtube shifter, but that isn't required.

PDXGS
08-06-2008, 03:45 PM
Heck, why stop there?
There are internally geared hubs that will eliminate the need for a derailler alltogether.
Check out Shimano and Rohloff ($$)
http://www.rohloff.de/en/products/speedhub/index.html

huss
08-06-2008, 03:57 PM
Just go fixed and save yourself....hahaha:D

fredlf
08-06-2008, 04:36 PM
I'm very slowly building up an "around town" bike that will have this set up. The one thing I've found is that one-speed cranks are ridiculously over-priced (probably due to the current fad of fixed). So I think I'm just going to use some MTB cranks with the two outer rings removed. That will have the added benefit of letting me add the rings back if I want an f. der. later.

The thing that strikes me as funny is, if i use modern road gear to build it up, I could actually have a 10-speed with no front derailleur!

Quentin
08-07-2008, 01:05 PM
Thanks for the comments. I have a single speed and a geared road bike, so either the Shimano Nexus 8 or single chainring/geared cassette sound like good choices. I'm a bike junkie so I always have a project brewing in the back of my mind. Every time I clean my drivetrain I think about how nice it would be if there was a viable option for keeping the drivetrain better protected from road dirt and grime. I read about some concept hydraulic drive systems and shaft-drive systems, but they just don't seem practical. It's interesting to ponder the future of bicycle drivetrain systems 10 or 20 years from now.

shnshni
08-08-2008, 02:20 AM
i rode with a single chainring in front and a derailleur iin back, but I could only shift between 3-4 gears before my chainline got too far off and my cahin fell off and screwed everything up. in my personal experience, it has been better to avoid the gears in back and just go with one.

Simple Nature
08-08-2008, 09:01 AM
If you want to go cost effective, you keep the middle ring and make sure you have good alignment and size your chain accordingly. You might also want to go to a short cage rear derailleur. Cassettes are available in wide range 11T-34T 9 speed.

If budget is no problem, check out Schlump's 3 planetary crank systems. These are 2 speed systems that have a wider range than most triple setups. Bundle this with a Rohloff 14 speed hub and you have a super wide range and a super efficient chainline. The Tech-Mech's dream at a small weight penalty. Of course, were talking ~$1.5K just for the gear train.

There is a middle of the road option in the SRAM DualDrive. 33% up and 33% down gearing that can replace the purpose of the front derailleur. They come in at about ~$250 plus lacing a wheel. They can also work to change 27 speeds to 81 speeds if so desired by retaining the 3 front chainrings.

Recumbent folk love wide gear ranges... especialy trikers. With 20" drive wheels, chains are always dragging in the dust and the stock drivetrain often runs out of umph way to soon for their liking. Or the large drive wheels make 16% grades a chore to climb especialy on a loaded tour. The Schlump and Rohloff route has been considered the pinnacle of recumbency gearing.