Old derailleur on 9 speed cassette

[Johnsqual]

Hello,

I have been trouble getting an old derailleur to work on a 9 speed cassette. I was under the impression that as long as the cassette, chain and shifters match (they do, all shimano 9 speed), the type of derailleur's not important.

Some detail:

My cross bike had a 9 speed campag veloce derailleur that worked ok but didn't shift too well into the lowest gear sprocket (28t). I found an old shimano exage 300 derailleur with a long cage in my bits box and decided to see if it performed any better. However, I cannot get it to shift across to the biggest or ever second biggest sprocket. I have set the L limit stop as loose as I can, but the derailleur just stops when I try to manually push it over. I also tried adjusting the B adjuster, which didn't help much either. It is as though the derailleur is not wide enough to shift across the whole cassette.

Am I doing something wrong, or is it just wrong to think any derailleur will work with any cassette?

Thanks for your help,

Johnny

 

[daccordimark]

Given the different cable pull to movement ratios of Campag and Shimano mechs you're lucky the Veloce shifted well at all - assuming your 9 speed Shimano is indexed. It might be that the old Exage mech just doesn't have enough movement to cope with the wider 9 speed cassette compared to old 6 speed freewheels.

Did you try adjusting the B-screw on the Veloce mech to see if that helped? Theoretically the biggest sprocket a short cage Veloce can cope with is 26 so a 28 might be asking too much.

Mark.

 

[Johnsqual]

Thanks Mark.

I did try adjusting the B screw and it helped a bit with the campag mech.

I was thinking that the old exage might be too limited in range of movement to help.

Is the claim that most mechs will work as long as you get the shifter-cassette
combination right complete nonsense? Or am I missing something?

Johnny

 

[hamster]

Exage 300 is a 7 speed (if I remember right) so it was designed for a narrower cassette.
Probably it was also intended for a steel frame, so a thinner dropout thickness taking it closer to the wheel.

Quite probably you have a build up of distances of thicker dropout (Alu frame?) and wider cassette so it won't reach.

 

[mattsccm]

You don't say what shifters you are using but I doubt thats an issue.
My Campag Veloce mech, 9 speed, works fine across a variety of casettes from 7 to 10 speed including a 28 sprocket.
Are you using Shimano shifters as they are availible in 7 speed and Campag Ergos are not. Are you using bar mounted shifters, thinking about it?

 

[Johnsqual]

Hello all,

Thanks for replies.

I started with (used) 9 speed veloce ergos, but the rear shifter gave up after about a year of cyclocross abuse. My LBS put a 9 speed shimano cassette on, which actually worked ok
(they originally put on a 10 speed cassette and set the limit stop at 9 speeds, presumably hoping I wouldn't notice. Shop has since closed down. I wonder why...)

I then transferred a set of shimano tiagra shifters, and found the old shimano 300 derailleur which has a long cage. I was hoping the long cage would help shifting to the biggest sprocket.

TBH with the mud in the middle of winter, I am thinking of just building a single speed cyclocross. No matter how good I get the derailleur to shift in the garage, it hardly shifts at all after about 200 metres into the mud.

Cheers again,

Johnny