internal geared hub and front derailleur?
Has anyone tried using a front derailleur and double crank with an internally-geared rear hub to increase the range of gear ratios available over use of the internally-geared rear hub alone? If so, can you describe how you handled chain tension and chain alignment problems?
|
Originally Posted by mrteddiamond
(Post 5824205)
Has anyone tried using a front derailleur and double crank with an internally-geared rear hub to increase the range of gear ratios available over use of the internally-geared rear hub alone? If so, can you describe how you handled chain tension and chain alignment problems?
|
+1. Either a RD or a single speed tensioner. I'm sure Sheldon's done this.
|
And you can buy bikes like that...here's one example:
http://www.schwinnbike.com/products/...ail.php?id=954 Shimano's Chain tensioner picture...You adjust the chain line by spacing the whole unit from the hanger with supplied washers...cheaper/easier to just use a rear derailleur, although some would argue the chain tensioner has a lot more spring tension. Some prefer Rennen, Sette, DMR, Yess, etc: http://img132.imageshack.us/img132/3...s500fs6og7.jpg |
And at the point where you're running a FD and either a RD or chain tensioner, what was the point of going with an internally geared hub to begin with? Seems like you're re-introducing the very type of complexities and problems of exposure to elements that the internally-geared hubs are designed to bypass.
|
Originally Posted by ginsoakedboy
(Post 5824657)
And at the point where you're running a FD and either a RD or chain tensioner, what was the point of going with an internally geared hub to begin with? Seems like you're re-introducing the very type of complexities and problems of exposure to elements that the internally-geared hubs are designed to bypass.
|
Originally Posted by tellyho
(Post 5824352)
+1. Either a RD or a single speed tensioner. I'm sure Sheldon's done this.
I used a classic Hurét Jubilee with the Shimano 8-speed on my Raleigh International, and a Rohloff chain tensioner on my Greenspeed trike with NuVinci continuously variable rear hub. Sheldon "Hybrid Gearing" Brown Code:
+-------------------------------------------------------------------+ |
Originally Posted by tellyho
(Post 5824352)
+1. Either a RD or a single speed tensioner. I'm sure Sheldon's done this.
|
Originally Posted by Sheldon Brown
(Post 5825821)
Right.
I used a classic Hurét Jubilee with the Shimano 8-speed on my Raleigh International, and a Rohloff chain tensioner on my Greenspeed trike with NuVinci continuously variable rear hub. Sheldon "Hybrid Gearing" Brown Code:
+-------------------------------------------------------------------+ |
Originally Posted by mrteddiamond
(Post 5825866)
In the end, was it worth it? Did the resulting drivetrain require less maintenance, in your opinion, than a pure FD/RD drivetrain?
I rode this bike very extensively without the derailer, 52/19, and it worked great. As my legs began to deteriorate due to my advancing MS, I added the 42 tooth ring to help with the steeper climbs. I didn't get to ride this setup very long before I became unable to handle a two wheeler, so wear was never an issue. The other big plus of this setup is that it shifts way better than a derailer system. On the Greenspeed trike, I only got to ride with the NuVinci a couple of miles before the snow and ice came. The NuVinci won't work with a standard rear derailer as a tensioner, due to clearance issues with the NuVinci shift linkage. Had to substitute the Rohloff tensioner for clearance. http://harriscyclery.com/nuvinci Sheldon "Limited Experience" Brown Code:
+--------------------------------------+ |
Thanks very much, Sheldon. I was hoping to hear that. I'll give this a try, then!
|
Sheldon,
I have posted this question in the folding bike forum, but, what about this possibility for a Raleigh Twenty with an SA 8 spd hub using 451 rims and a 48t chainring and wanting a smaller 2nd ring? |
Originally Posted by stevegor
(Post 5827014)
Sheldon,
I have posted this question in the folding bike forum, but, what about this possibility for a Raleigh Twenty with an SA 8 spd hub using 451 rims and a 48t chainring and wanting a smaller 2nd ring? However, I generally don't like derailers on folding bikes. Sheldon "Been There, Done Most Of That" Brown |
OK thanks Sheldon, but....please excuse my annoying ignorance, can I do it without a RD or a chain tensioner?
|
Originally Posted by stevegor
(Post 5827964)
OK thanks Sheldon, but....please excuse my annoying ignorance, can I do it without a RD or a chain tensioner?
Sheldon "Brevity" Brown |
It is possible to do anything, but I would say that it would not work very well without a tensioner. For a normal sort of front drive setup, the chain rings are usually different sizes by around 10 teeth - 5 chain links difference would create quite substantial slack.
|
I can't really add anything more except my own personal experiences with similar setups...
I don't like derailers that much and with the right internal gear hub having adequate gear range should not be an issue. I have played with different setups and did have a dual cog on an SA AW hub and used a rear d and thumb shifter to switch ranges and also ran a Shimano 3 speed with a dual chain ring and used a derailer to handle the tensioning duties. I liked the SA AW setup with the dual cogs and tensioner from a functional point of view but hated the cluttered look of the derailer and found I can get by pretty well with 3 speeds... most of my miles are done on bikes that have one speed and don't coast. Other people might appreciate the high/low range this setup offered. You can run an SA hub with 3/32 chain and 3/32 chainrings if you replace the SA cog with a cog from a Shimano 3 speed and use spacers or can use 2 Shimano cogs with the existing SA spacer (this is what I did). I believe that Harris Cyclery also carries dual cogs for 3 speeds. With a double chain-ring you need to have decent take-up at the rear and I would use a derailer rather than a tensioner (most won't even work with this setup) as the take-up capacity is greater, there's more tension, and the derailer can be set so that it is static and keeps the chain line optimal. You can often do this with the set screws or simply reverse a shifter cable, insert it into the derailer (backwards) and then use that and the d barrel adjuster to set the derailer position. I might have a picture of the derailer setup I used somewhere... |
|
|
You mention that you measured the cable distance with shifting and were going to try a brifter with a travel agent. Have you done this yet? I have an 8 speed and would love to know if someone's tried it and it worked.
|
it might be fiscal overkill, but you could you a schlumph mountain drive crankset/bottom bracket. i know i spelled that wrong.
|
Originally Posted by anielsen
(Post 5835755)
You mention that you measured the cable distance with shifting and were going to try a brifter with a travel agent. Have you done this yet? I have an 8 speed and would love to know if someone's tried it and it worked.
Someday I'll do that test. |
i'm going to resurrect this thread because i am thinking exactly about the hybrid gear option. I'm currently building a light touring bike from a 1960s Wally Green frame. The rear drop outs don't have a derailleur hanger and spacing is about 122 (i think). I could get a 5-6 speed cluster in there without spreading the stays too much, but, then I'd have to use a fugly bolt on hanger and no indexing! Anyway I have a SA SRF-3 rear wheel on my commuter which I thought of swapping out. In the front I'd use a stronglight 49D with 52/32 gearing for steep hills. Having only one cog in the back would significantly reduce chain rub otherwise common with a cluster in the back. . It is very Sheldonesque!
|
Since you bumped a five and a half year old thread, we're gonna need pics.
|
Originally Posted by Kimmo
(Post 16003175)
Since you bumped a five and a half year old thread, we're gonna need pics.
I didn't even notice the dates until I saw the first post from Sheldon Brown. That was a trip! |
All times are GMT -6. The time now is 08:07 AM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.