SRAM red rear derailleur adjustment

General Help
1

I’m trying to get an SRAM red rear derailleur to work on properly on a Litespeed Ti…

The chain when in the big c/ring and small cog keeps jumping (not to the next smallest cog), just up and down a bit.

Every other gear is sweet - the end has been set at the big cog.

The weird thing is, I seem to have run out of ‘outside’ adjustment on the small cog end, that is, I can’t set the derailleur any further to the outside (toward the dropout).

It keeps happening at the same cog tooth every time around, and it’s really starting to give me the sh!ts.

Have removed the derailleur, reset the end points, checked assembly, checked derailleur hanger is straight with a gauge, removed and refitted the cassette. All the parts are new.

Is there anything ‘trick’ about SRAM red I need to know? Campag/Shimano is heaps easier…

thanks fellas

2

SRAM road derailleur are sensitive to a couple of things b-tension and outer gear cable length and chain length. But it sounds like the rd tab on the frame may be a bit thin to put the upper cog where it wants to be you can get shims from wheels manufacturing which will place the rd a little more out board. Where are you in oz.

Edit: i mean the top pulley wheel not the cog too many red wines sorry.

3

Also, if you have a quick link, make sure it’s facing the right way. Can cause chain to jump.

4

This, especially as it’s a Ti frame, not alloy / crabon with alloy hanger.

5

sooo…you ride 53-11 a lot?

6

are you asking him out??

7

Yeah that may be the case. The top adjust was WAY up into spokes too.
I’m in Melbourne.

Quick link is around the right way; that’s happened to me before.
The chain is jumping not just when the link goes through.

Haha. Not even my bike. So even more shitty about it!

8

I normally don’t have any issues with red adjustment. In fact it is usually the case that you can adjust the limit screw to let the chain drop off the the outside of the 11t cog. Between the frame and cassette.
Not knowing exactly what you are running in combo I will off a couple of points that can trip you up.
If you are using a sram cassette then don’t use any shim/spacers behind the cassette unless on a Mavic. If on a Mavic then use only the Mavic specific spacer. If you are using a Shimano cassette then use the slim shimano shim where required.

I don’t understand “the end has been set at the big cog.”
Have you tried to set it from the largest cog first? If so set from the 11t cog first with no cable tension. Apply tension afterwards.

If you are using a connex (whipperman) link with an 11t cog it will skip. It will skip really bad if it is the wrong way around and still skip a bit even if fitted correctly. On a sram chain use the powerlink. on a 12t no probs.

I set b-screw tension only on the inner(largest cog) at a gap of around 6mm between teeth of cassette and top jokey. This should have almost no effect at the 11t cog however.
With the chain length the old “axel-top jockey-lower jokey” all in a straight line works great. No shorter.

If you could post the hub/wheel brand-cassette(include ratio)-chain(joining method) that may shed some light.

E

9

Go to the Sheldon when in need… Derailer Adjustment

10

mucked around with it last night. it is consistent with Slinky’s diagnosis;

if i undo the derailleur a fraction from the hanger, it is perfect.

looks like i need to get one of those spacers. I doubt it’s something a BSC would carry?

11

just an fyi for anyone who might have this issue in the future - don’t buy SRAM.

nah, but I made a washer to go b/w frame and derailleur, and it works perfectly.

12

Tongue-in-cheek?

13

actually no, my response was really ambiguous.

I found red rear der a real pain in the arse to tune - even with setting Low and High stops, they seemed really inconsistent

e.g. it seemed like the cables weren’t bedded into the guides or shifters

don’t know if others have found it is hard to tune too, but Campag and Shimano have been no issue at all in the past for me.

thoughts?

14

I have always found Red to be very easy.

15

Are you using the gore cables it helps to get them running smooth also they require less cable tension than shimano and campag. Also have a nice big curve in the rear der cable going into the mech and watch the b-tension.

16

The reason I asked is because:

My rear slams the changes home with a confident snap. The wind blew my bike over and bent my derailleur but not the hanger, so maybe thats the key to my success.

17

Always ghetto lock your carbone bike to something… Then the winds huffing and puffing amounts to nothing…

18

I’d just finished riding to Gosford and it was leaning against a tree. I didn’t want to carry a 3.14m long cable lock for 108km!

19

Ghetto locking is using your helmet as a lock

20

an update on this -
derailleur hanger was slightly bent
derailleur carbon cages were out of tollerance, so put the whole system out
SRAM guys I think are looking at the deraileur…