I have a 12 year old mountain bike with a worn out Deore DX rear derailleur. My drivetrain is 7-speed -- can I replace the derailleur with one from an 8 or 9-speed drivetrain?
Basically it boils down to this -- is the index spacing of 8 and 9-speed drivetrains the same as the index spacing on a 7-speed? If so then I should be fine.
If anyone has information on replacement derailleur compatibility it would be appreciated. Please reply to me directly and I will summarize to the list.
I have a 12 year old mountain bike with a worn out Deore DX rear derailleur. My drivetrain is 7-speed -- can I replace the derailleur with one from an 8 or 9-speed drivetrain?
Basically it boils down to this -- is the index spacing of 8 and 9-speed drivetrains the same as the index spacing on a 7-speed? If so then I should be fine.
If anyone has information on replacement derailleur compatibility it would be appreciated. Please reply to me directly and I will summarize to the list.
Many thanks! Yggy
Only the shift lever is indexed so almost any derailleur will shift 7 speed cogs if you set the limit screwws correctly. The pivot points on the derailleur wear out over time so finding a derailleur that uses good bushings at the pivot points would probably last longer. The cheapest Shimano tourney series derailleurs for example seem to wear out after only one set of jockey wheels but that is still over 15,000 miles of road use.
"Yggy King" <[email hidden]> wrote in message news:<zN39d.12419$a41.2206@pd7tw2no>...
Quoted message said:
I have a 12 year old mountain bike with a worn out Deore DX rear derailleur. My drivetrain is 7-speed -- can I replace the derailleur with one from an 8 or 9-speed drivetrain?
Basically it boils down to this -- is the index spacing of 8 and 9-speed drivetrains the same as the index spacing on a 7-speed? If so then I should be fine.
If anyone has information on replacement derailleur compatibility it would be appreciated. Please reply to me directly and I will summarize to the list.
Many thanks! Yggy
I just replaced my 1991 Deore DX 7 speed derailleur on my touring bike. It came from a 1991 Trek 520 with bar end index shifters. It would not clear a 34 tooth cog on my new Redline touring frame. So I replaced it with a brand new 9 speed Deore derailleur. The cheap $20 black one. Still using the same 7 speed cassette and 7 speed index bar end shifters. Works just fine. And it clears the 34 tooth cog easily. All Shimano derailleurs, except Dura Ace until the late 1990s, were interchangeable among brands and number of gears, 7-8-9.
On 7 Oct 2004 08:46:43 -0700, [email hidden] (Russell
Seaton) said:
"Yggy King" <[email hidden]> wrote in message news:<zN39d.12419$a41.2206@pd7tw2no>...
Quoted message said:
I have a 12 year old mountain bike with a worn out Deore DX rear derailleur. My drivetrain is 7-speed -- can I replace the derailleur with one from an 8 or 9-speed drivetrain?
Basically it boils down to this -- is the index spacing of 8 and 9-speed drivetrains the same as the index spacing on a 7-speed? If so then I should be fine.
If anyone has information on replacement derailleur compatibility it would be appreciated. Please reply to me directly and I will summarize to the list.
Many thanks! Yggy
I just replaced my 1991 Deore DX 7 speed derailleur on my touring bike. It came from a 1991 Trek 520 with bar end index shifters. It would not clear a 34 tooth cog on my new Redline touring frame. So I replaced it with a brand new 9 speed Deore derailleur. The cheap $20 black one. Still using the same 7 speed cassette and 7 speed index bar end shifters. Works just fine. And it clears the 34 tooth cog easily. All Shimano derailleurs, except Dura Ace until the late 1990s, were interchangeable among brands and number of gears, 7-8-9.
You are probably smart staying with the 7 speed cassette. When I changed from 6 to 7 speed freewheels I gained a little over 3 mm's of cluster width. Now the smallest cog on the freewheel has a poorer chain line than it did on a 6 speed cluster. My 16 tooth and 18 tooth sprockets run smooth so I'm not complaining. The 16 / 52 combination gets me to 23 mph which is plenty fast. Replacement parts are very economical for 7 speed setups for sure, rugged 7 speed chain costs a lot less than that narrow stuff!
I have a 12 year old mountain bike with a worn out Deore DX rear derailleur. My drivetrain is 7-speed -- can I replace the derailleur with one from an 8 or 9-speed drivetrain?
Yes, there's no problem with this.
Quoted message said:
Basically it boils down to this -- is the index spacing of 8 and 9-speed drivetrains the same as the index spacing on a 7-speed?
No, but that is a matter to be determined by the shifter and the cassette. The derailer doesn't care how many gears there are.
Virtually all Shimano rear derailers index the same and can be interchanged among different numbers of speeds.
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