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any way to make modern rear derailleurs work non-index?(11 posts)

any way to make modern rear derailleurs work non-index?secourir
Jan 22, 2002 12:09 AM
sorry, but had to ask

im looking to build up a new 7/14 speed bike with old school friction downtube levers but think that a new modern rear derailleur would be better than a used old design version - but i dont need the sis or sti shifting. i am happy to change my own gears.

i will also be building new wheels using phil wood freewheel hubs and buying as many sram-sachs 7 speed freewheels as i can as i want to use new bits.

is it possible? kind of embarrased to ask.

re: any way to make modern rear derailleurs work non-index?APSBiker01
Jan 22, 2002 12:43 AM
The only thing you have to do is make sure that the set screws are set so that you can't overshift -- 7 speed rear cogs are narrower than the 8/9sp ones. Your LBS can help you with this.

re: "all rear derailers from the same manufacturer operate the "Russty Coggs
Jan 22, 2002 7:25 AM
Absolutely right in the friction mode. Pre 9 speed DA rear derailers only work with pre 9 speed DA shifters. Campy also changed the throw ratio on 9 and 10 speed rear derailers for the 2001 model year.Friction is one story,index is another.
7 speed rear cogs are narrower than the 8/9sp oneswilbur
Jan 22, 2002 8:20 AM
Horse dung. The cogs themselves are not narrower, nor is the spacing on a 7 speed.
He means "group". nmWilmar
Jan 22, 2002 10:06 AM
Group?! try againFreda
Jan 22, 2002 10:26 AM
maybe cosget, cassette, or freewheel
Group, group, group buddy......
Jan 24, 2002 2:10 AM
Just cos they don't call 'em that in YOUR country, don't mean they aren't called that everywhere. Have a little more width to your outlook :-)

Fender? Hood? Pissed?

Get it?
The derial is not indexed//Dr Death
Jan 22, 2002 1:27 AM
Only the shifters - friction shifters+any derail = non-index shifting.
Shifters index, not derailleurs. No problem...............(nm)Dave Hickey
Jan 22, 2002 3:46 AM
Not an issue, exceptKerry Irons
Jan 22, 2002 4:21 PM
that the throw of the shift lever will be smaller as you go up in cog count. The newer derailleur will actually shift a bit better, but with narrower cog spacing, it's a bit harder to manage friction shifting. Not impossible, but more difficult.
All Friction With Any Derailluer is No ProblemWheels
Jan 23, 2002 4:11 PM
If you use all friction to shift the RD, ANY derailleur will do for a 7-speed cogset. Here is why.

The cogs don't care what the RD-type is and the friction shifters don't care what the cogs or RD is. I run a old 7-speed SIS down tube shifter set up to an old RD. I have the shifting set to pure friction mode and routinely swap 7-, 8-, and 9-speed wheels without any shifting problems with the same RD.

Since the shifters are in friction mode, they don't move with a step function as SIS or STI does. Therefore, minute adjustments can be made just by moving the shift lever to eliminate chain noise. That is what is nice about friction mode.

Also, the RD has no effect on the ability to shift from 7- to 9-speed cogs. The RD is just basically two pulleys in moving, scissor/pivot-like mechanism. The mechanism opens (low gear/bigger cog) by tension in the shifter cable and closes (high gear/small cog) via relaxation of a heavy-duty spring when the cable tension is released. 7-speeds RD have enough travel to accommodate 7-, 8-, or 9-speed cog clusters. The only thing is that you will need to fully open the set screws an a older 7-speed RD in order to allow for the wider 8 and 9-speed cogset.

Finally, since you're in Friction mode, you can run a Campy, Shimano, or Suntour RD with any friction shift system. Even the cogs don't have to match the brand of RD or Shifter.