Have questions or want to discuss cycling? Join Now or Sign In to participate in the BikeRide community.

New: Take part in the July Giveaway for a brand new 26" Thruster® Street Style BMX Cruiser Bicycle

New product launch: WIN an innovative aeroe Spider Rear Rack


No tension in main pivot of rear derailleur (Sram X7)
#1
Hi, I have just bought a custom built Azonic gravity frame downhill bike but there is a problem with the rear derailleur. The main pivot, as you can see from the picture, has no tension so does not pull the chain at all and it is, therefore, way too slack. Does anyone have any suggestions on how to fix this or do I need a new one. Thanks
  Reply
#2
The seller should replace it.
Nigel
  Reply
#3
Oh okay, thanks. Do you know what size derailleur I need though? I have a SRAM X7 (2006) and I have a single chainring on the front and the bike is a downhill. Small, medium or large? Thanks
  Reply
#4
(12-02-2013, 04:26 PM)TKdownhill Wrote:  Oh okay, thanks. Do you know what size derailleur I need though? I have a SRAM X7 (2006) and I have a single chainring on the front and the bike is a downhill. Small, medium or large? Thanks
You need a long cage rear derailleur - 100mm as SRAM spec's them. You can find X.3, X.5, X.7 and X.9 that will work.

http://www.amazon.com/SRAM-Long-Cage-Derailleur-Black/dp/B002K95REI/
http://www.amazon.com/SRAM-9-Speed-Rear-Derailleur-Long/dp/B003RLFNOW/
Nigel
  Reply
#5
(12-02-2013, 06:02 PM)nfmisso Wrote:  
(12-02-2013, 04:26 PM)TKdownhill Wrote:  Oh okay, thanks. Do you know what size derailleur I need though? I have a SRAM X7 (2006) and I have a single chainring on the front and the bike is a downhill. Small, medium or large? Thanks
You need a long cage rear derailleur - 100mm as SRAM spec's them.

Nope, for downhill you need the short cage:
http://www.sram.com/de/sram/mountain/products/sram-x7-10-gang-schaltwerk
(sorry, German version)
(The OP has a single chain ring in the front, so no need for really high capacity)
The long cage would work, too, just not as well (plus risk of it catching some root or stuff is higher).
  Reply
#6
(12-03-2013, 02:29 AM)Joe_W Wrote:  
(12-02-2013, 06:02 PM)nfmisso Wrote:  
(12-02-2013, 04:26 PM)TKdownhill Wrote:  Oh okay, thanks. Do you know what size derailleur I need though? I have a SRAM X7 (2006) and I have a single chainring on the front and the bike is a downhill. Small, medium or large? Thanks
You need a long cage rear derailleur - 100mm as SRAM spec's them.

Nope, for downhill you need the short cage:
http://www.sram.com/de/sram/mountain/products/sram-x7-10-gang-schaltwerk
(sorry, German version)
(The OP has a single chain ring in the front, so no need for really high capacity)
The long cage would work, too, just not as well (plus risk of it catching some root or stuff is higher).
Good point Joe; that maybe why there is a problem with his current long cage RD.....
Nigel
  Reply
#7
Now I actually took a second look at the pictures... yeah, that seems like a long cage dérailleur. However, it still does look weird. The cage should be closer to the body without the chain running through it (upper picture), shouldn't it? (like the OP mentioned, it is likely broken, or looks broken to me)
  Reply
#8
(12-03-2013, 04:51 PM)Joe_W Wrote:  ......The cage should be closer to the body without the chain running through it (upper picture), shouldn't it? (like the OP mentioned, it is likely broken, or looks broken to me)

Yes, the cage should be almost parallel to the ground when the bike is on both tires on the ground, with no chain, the picture shows it almost perpendicular to the ground.
Nigel
  Reply
#9
Hi, I have the X7 Medium cage, on my derailleur behind the SRAM X7 Logo (close to the upper small derailleur cog) is a small clip, if you pull this clip out then the bottom derailleur cage will separate and you will see a big spring. The tension from the derailleur comes from this spring. If your derailleur is the same then it is likely broken or not properly installed. If you are careful about removing the clip you should be able to check this without causing any damage, if you see anything you cannot fix, then take it back to the shop.
  Reply
#10
A common problem is that someone will take apart a deraiileur or remove a stop pin and allow the spring to unwind. It is not broken in such cases, just needs to be retensioned. This page shows the process for taking apart a derailleur (not necessarily identical with yours) and the deore rear 4.jpg photo on post #10 shows both the spring and the pin.
  Reply
#11
Have you tried the B tension screw. I have a Sram X7 as stock on a hard tail with a triple up front. I hard a similar problem playing with it trying to get it shift better.
  Reply
#12
No, the problem is the spring. With no chain tension the normal spring will cause the cage to rotate as far clockwise as it can (until it hits the pin/stop) pointing back and close to horizontal. His derailleur cage is pointed almost straight down.
  Reply


Possibly Related Threads...
Thread
Author
Replies
Views
Last Post
 
197
06-06-2020, 03:20 AM
Last Post: jonsio
 
5,346
06-28-2017, 12:52 AM
Last Post: jacke
 
12,941
05-14-2015, 05:55 PM
Last Post: DaveM

Forum Jump:

[-]
10 Latest Posts
Creaky crank with play and loosening
Today 10:04 AM
Dork disc - remove it or keep it?
Today 10:02 AM
26" Thruster® Street Style BMX | July 20...
Today 08:23 AM
2020 road cycling season
Today 07:18 AM
Post a photo for aeroe Spider Rear Rack
Today 07:03 AM
FD cable pull on opposite side of frame
Today 04:18 AM
60s Viner Repainted..?
Yesterday 06:23 PM
budget speedometer
Yesterday 10:44 AM
Pinging noise fixed
Yesterday 08:08 AM
Need advice on Bike Rack
Yesterday 02:07 AM

[-]
Top 5 Posters This Month
no avatar 1. Jesper
72 posts
no avatar 2. CharleyFarley
20 posts
no avatar 3. Painkiller
15 posts
no avatar 4. Papa Dom
10 posts
no avatar 5. G_M
8 posts