XT 9-speed rear mech replacement question
08-04-17, 10:33 AM
#1
XT 9-speed rear mech replacement question
Hi,
I have an XT 9 speed rear mech (SGS) on my touring bike that will at some time soon need replacing. The model number is FD-M76 or -761. I bought it in 2007 or 8, and it has a barrel adjuster. I also have an XT triple crank and front mech.
I have searched a few websites, but it seems modern 9 speed XT rear mechs have changed and they aren't suitable as a replacement.
Any ideas much appreciated.
I have an XT 9 speed rear mech (SGS) on my touring bike that will at some time soon need replacing. The model number is FD-M76 or -761. I bought it in 2007 or 8, and it has a barrel adjuster. I also have an XT triple crank and front mech.
I have searched a few websites, but it seems modern 9 speed XT rear mechs have changed and they aren't suitable as a replacement.
Any ideas much appreciated.
08-04-17, 10:37 AM
#2
Banned
there have been some changes but rear mechs just move in and out, they dont have "speeds"
thats a cassette cog number and the matching detent count and spacing in the shift lever..
thats a cassette cog number and the matching detent count and spacing in the shift lever..
08-04-17, 10:55 AM
#3
Senior Member
Shimano still makes a few 9-speed RD's that have barrel adjusters (Deore M591 comes to mind), which should probably work fine on your bike. Does your bike have a barrel adjuster anywhere else between the shift lever and the RD? If so you don't really need a second one on the RD anyway.
Also, you need to make sure of the exact model number of your old RD. There is a big difference between the RD-M760 and RD-M761. The M760 is a "Rapid Rise", aka low normal design, which Shimano doesn't make anymore, while the M761 is a conventional "top normal" design which can be replaced easily. If you have a Rapid Rise RD, you may need to change out your shift levers if you want to switch to a top normal design (unless you have something like bar end shifters which will work either way).
Also, you need to make sure of the exact model number of your old RD. There is a big difference between the RD-M760 and RD-M761. The M760 is a "Rapid Rise", aka low normal design, which Shimano doesn't make anymore, while the M761 is a conventional "top normal" design which can be replaced easily. If you have a Rapid Rise RD, you may need to change out your shift levers if you want to switch to a top normal design (unless you have something like bar end shifters which will work either way).
08-04-17, 10:56 AM
#4
Expired Member
I guess you know you don't want 10 speed as it will not work with your shifters (assuming you have indexed 9 speed.) Any 9 speed XT, LX or Deore should work fine, but I would avoid "rapid rise" or "shadow" versions and prefer one with a barrel adjuster. SHIMANO Deore LX RD-M571 MTB Bike 9-speed Rear Derailleur SGS | eBay another example Shimano Deore M591 9 SPD Rear Derailleur > Components > Drivetrain > Rear Derailleurs | Jenson USA
Last edited by shelbyfv; 08-04-17 at 11:09 AM.
08-04-17, 11:31 AM
#8
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True for Shimano up until the introduction of Dynasys. That won't work with 9 speed cassettes or shifters.
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Old School…When It Wasn’t Ancient bikepacking
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Pokin' around the Poconos A cold ride around Lake Erie
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08-04-17, 11:41 AM
#9
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Hi,
I have an XT 9 speed rear mech (SGS) on my touring bike that will at some time soon need replacing. The model number is FD-M76 or -761. I bought it in 2007 or 8, and it has a barrel adjuster. I also have an XT triple crank and front mech.
I have searched a few websites, but it seems modern 9 speed XT rear mechs have changed and they aren't suitable as a replacement.
Any ideas much appreciated.
I have an XT 9 speed rear mech (SGS) on my touring bike that will at some time soon need replacing. The model number is FD-M76 or -761. I bought it in 2007 or 8, and it has a barrel adjuster. I also have an XT triple crank and front mech.
I have searched a few websites, but it seems modern 9 speed XT rear mechs have changed and they aren't suitable as a replacement.
Any ideas much appreciated.
If you do really need to replace it, you can still find them. Jenson USA sells an SGS for $65. There are others out there.
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Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Plan Epsilon Around Lake Michigan in the era of Covid
Old School…When It Wasn’t Ancient bikepacking
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
08-04-17, 12:44 PM
#10
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If you like the derailleur, the first step is to find out exactly which derailleur you have. If it is a 760, it is rapid rise, if it is 761 it is a regular high normal. Since it is working now, go on eBay and look for an NOS or one that has hardly been used. It may take a bit of time, but you can find one.
I have purchased a couple dozen eBay rear derailleurs and only remember one that had an issue where I couldn't use it. I think the last rear derailleur I bought elsewhere was a 7400 in 1987. Just take your time and look at the pictures to see if it has been used and abused.
John
I have purchased a couple dozen eBay rear derailleurs and only remember one that had an issue where I couldn't use it. I think the last rear derailleur I bought elsewhere was a 7400 in 1987. Just take your time and look at the pictures to see if it has been used and abused.
John
08-04-17, 03:10 PM
#11
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I don't know what you are doing to your derailer but there really shouldn't be a need to "replace it" as a preventive measure. In my experience derailers seldom (if ever) wear out. I have an XT on my touring bike that has been there since 2003 and has around 10,000 miles on it. I've never even replaced the jockey pulleys. I have another XTR on my commuter bike that has been going strong since 2006 and has 17,000 miles on it. Neither is babied.
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08-04-17, 06:28 PM
#12
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I agree that rear derailleurs last a long time on a road bike and there may not be much need to have a backup. But if someone wants to run older quality 9 speed or less setup it is a small investment to have an extra rear or even a front derailleur. If bar or trigger shifters are being used it would be nice to have a backup.
I particularly like rapid rise with trigger shifters, and with my wife's brifters. I have had one break on a mountain bike and I had to scramble to find one. I won't have to do that again. When you look at the cost of a new bike, a few backup parts are a nit.
John
I particularly like rapid rise with trigger shifters, and with my wife's brifters. I have had one break on a mountain bike and I had to scramble to find one. I won't have to do that again. When you look at the cost of a new bike, a few backup parts are a nit.
John
08-04-17, 08:43 PM
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open Ebay... run a search for "XT 9 speed Rear"... bid or buy now... all will work... you must only determine if your present der. is rapid rise/shadow, or normal...
rapid rise/shadow is backwards to normal.... RR shifts to big gear in back when released... normal shifts to small when released...
rapid rise/shadow is backwards to normal.... RR shifts to big gear in back when released... normal shifts to small when released...
08-05-17, 12:37 AM
#16
I suppose I have the "what if" problem. Before every tour, I have this problem. The drive chain, with the exception of chain and cassette, have done 10 000 or so km. I'm touring northern Laos (mountains) this year. My experience of Madagascar and Cuba in previous years has taught me that it will be difficult, if not impossible, to find parts. Hence, for the sake of peace of mind, I was thinking it might lessen the risk if I did a little preventive maintenance.
Thanks to the input here, I know what I should buy. Thanks.
Thanks to the input here, I know what I should buy. Thanks.
