cohophysh

So I am shopping for MTB parts for my rebuild, if the item doesn't specifically say, how do I know if I am getting a friction derailler or a index? I currently have a shimano xt front derailler and am looking for shifters and rear derailler. is the xt a friction or index? sorry if this is confusing

Sheldon Brown

If the derailer was made in the last 20 years, it is indexable. All indexable derailers also work with friction shifters.

Sheldon "Easy One" Brown

superunleaded

Hi Mr. Brown,
Is there a way to get a Dura Ace ax rear der into friction?
I tried to use a DA ax rear der for a 7 or 8 speed indexed shifters but the ax rear der looks like its indexed for 6sp. I even tried disassembling the derailleur thinking I can grind those teeth from the der but now I can not even put the darn thing back to working condition. This is the part where the loaded spring goes back into the dropout bolt.

thank you in advance for any tips...
sincerely,
-gas

grolby

Dura-Ace derailers and shifters from before 1997 or so (8-speed DA or older) use a different cable pull ratio than other indexed Shimano shifters or derailers.

Shimano has published an alternate cable routing that allows an older DA shifter to be used with a non-DA derailer. Unfortunately, there is no solution for running things the other way around, other than getting a compatible (i.e. older DA) shifter.

Sheldon Brown

I don't believe that was made for indexing. The Dura-Ace AX was from the early 1980s, before the introduction of SIS.

If you have a Dura-Ace AX derailer that's in decent condition, sell it on eBay, it is a museum piece, and belongs on a restoration project, not a "rider." Even a new $20 Tourney will work WAY better.

Sheldon "Derailers Are Cheap" Brown

superunleaded

The original plan was to build the bike with full AX components but after testing the shifting with the rear der, I found out that the rear der has this serrated part that makes shifting SIS like. It has postive stops for 6 speed shifting which I find annoying that's why I wanted to go friction.

grolby

Oh, well that's completely different - I would strongly suggest that you follow Sheldon's advice. I doubt that there is any way to make the derailer work as you like without machining it to remove the offending bits. On these components, such a step would constitute a high crime. If you must, you can make it work by simply using it with a 6-speed freewheel. But Sheldon's idea is better. It'll fetch you a pretty penny if you sell it, and a brand-spanking new derailer from any of Shimano's component lines will work far better anyway.

superunleaded

I'll just throw the AX parts in a bin and wait for the next project that is suited for that kind of components. In the meantime, I decided to go to a full DA 7410 build.
Here is the project: https://www.bikefanclub.com/gallery/s...500&ppuser=121

-gas

DMF 

That's like throwing away money.

If you don't want the eBay hassle, please offer them on the Vintage forum. Someone would love to have them, I'm sure.


(Or did you mean bin as in storage, not as in trash? Maybe my vocabulary has become infected with Limey disease...)

operator

I think the context here is bin as in storage...

superunleaded

"I'll just throw the AX parts in a bin and wait for the next project that is suited for that kind of components."

When it comes to bike parts, nothing gets thrown away. They just wait... and wait, and wait for the next appropriate build. Appropriate for me anyway.

I got too many parts in boxes and bins that I have collected over the years. That and bikes hanging on the rafters

superunleaded

Sorry cohophysh, I didn't intend to crash your thread.
I'll just go back to the c&v.
https://www.bikeforums.net/classic-vintage/259478-current-inventory-how-fill-up-your-garage-bikes.html

TallRider

Just so the general principles get out there:
Rear deraillers are not indexed. Rather, they have cable-pull ratio (how far does the cage and pulley wheels move for a given amount of cable pulled by the shifter). If this amount of cable-pull lines up with the amount of cable-pull per click/increment of an indexed shifter and the spacing of the rear sprockets that you're using, then you're in business to use indexed shifting. All Shimano rear deraillers and rear shifters built since the advent of indexed shifting are compatible (same cable-pull ratio) except for pre-9-speed Dura Ace. So a 105 rear derailler that originally came with 6-speed down-tube shifters and 6-cog freewheel will work with 9-speed cassette sprockets and 9-speed STI shifters.

With friction shifting, you don't have these compatibility worries because there are no increments that you need to line up. Anything can be used with anything if you're running friction shifters, pretty much.

superunleaded

But I ran on to this Dura Ace AX rear der and it is indexed. Shifter is friction but the der is indexed to 6 speed. So I'd say all rear derailleurs works with friction shifting exept for this model. I'm not sure how many different AX models came out but this particular derailleur I got is indexed. No matter how much I fine tune my friction shifting, the der guide will line up within the 6 indexed stops.
I only have 1 AX rear der so I can not compare how the other AX works.

Anybody out there with DA AX rear der care to chime in?
Do your der have those positive stops that makes friction shifting annoying?

cohophysh

no worries

superunleaded

By the way, indexing happens at the shifter side, except for this Dura Ace AX rear der.
So when you buy any XT stuff, it is indexed at the shifter and the deraileurs will work with either friction or indexed shifters.

grolby

This is only almost always true. Earlier attempts tried to put the indexing stops in the derailer (e.g. Shimano Positron and, apparently, Dura-Ace AX). This is probably part of why they didn't work well! Otherwise, this is true.

By the way, some will claim that the "6-speed" 105 derailer will not function properly with 9-speed equipment, supposedly due to the cage being too wide. Nonsense! I'm tempted to use my 6-speed 105 derailer with new 10-speed 105 equipment, just for laughs (and because, hey, why the heck not?). But then I come back to reality - even "cheap" 10-speed 105 is way outside of my budget!