Troubleshooting SR11 RD

[summilux]

I recently built up a C50 with new SR11 (2011). With about 150 miles on the group, the RD shifting is giving me problems. I can't seem to get the tension right for shifting through all 11 cogs. I'll fix it on the stand, and then a few shifts into the ride I have to adjust. Then I have to adjust again, sometimes in the opposite direction. Once the ride is over I'll put it back in the stand and adjust again. But the next ride, I'll keep adjusting again. I've been through this cycle 3-4 times already.

The cable routing seem good. Cables were new and I assume that they've stretched out already. Any suggestions on possible issues that I should be checking out?

On the plus side, the FR shifting is freaking amazing (if such words could be used to describe gear shifting).

[djdj]

Sounds like maybe you didn't make sure the cable is taut before you attach it to the RD. For 10 speed, I pull it snug with pliers before tightening the bolt.

[buldogge]

I'm having a similar issue on my Chesini with Chorus 11. Have you checked the hanger alignment?

Also, make sure there is no undue friction. My metallic Jagwire outer was a tight fit at the Ergo and I fear that may be the culprit.

-Mark in St. Louis

[Tonger]

I'm not a master tech by any means but I had trouble with my Chorus 11 rear shifting after having the bike built at a Campy Pro Shop. My situation was that the cable could be adjusted to either upshift perfectly or downshift perfectly but not both at the same time. My tech had routed both the shift cables in front of the handlebars with the brake cables which made for a very tidy package, but the angle going around the bend in front was a lot more severe than routing them behind the bars.

After putting it off, I got a new set of cable housings (longer) and routed both shift cables behind the bars to lessen the angles. This apparently made a significant difference in cable friction. To shift into smaller cogs, the system relies on the spring tension in the derailleur. If there is too much friction, it has trouble taking all the slack out of the cable and the derailleur doesn't move outside as much as it should. This can be compensated by adjusting to take more tension out of the cable, but can result in poor shifting when going to bigger cogs.

By eliminating as much friction as possible, there is a "sweet spot" where you can adjust tension out of the cable just to the point where it just shifts into the smaller cogs perfectly. This point is where you preserve as much tension in the cable as possible for shifting into the larger cogs - while still maintaining the quality of shifting into smaller cogs. On the road you can add just a little boost to get into the larger cogs by just pushing the shift lever a little "extra" beyond the click.

Hope this helps. I know there are experts who probably have a more elegant method but this is what worked for me.

Tonger

[oldpotatoe]

I recently built up a C50 with new SR11 (2011). With about 150 miles on the group, the RD shifting is giving me problems. I can't seem to get the tension right for shifting through all 11 cogs. I'll fix it on the stand, and then a few shifts into the ride I have to adjust. Then I have to adjust again, sometimes in the opposite direction. Once the ride is over I'll put it back in the stand and adjust again. But the next ride, I'll keep adjusting again. I've been through this cycle 3-4 times already.

The cable routing seem good. Cables were new and I assume that they've stretched out already. Any suggestions on possible issues that I should be checking out?

On the plus side, the FR shifting is freaking amazing (if such words could be used to describe gear shifting).

Make sure the housing is long enough.

Route der housing behind the handlebar

make sure the 4mm housing at the lever is cut very clean.I use some Boeshield inside the housing

NO FERRULES in the levers, for brake or der.

Use 5mm housing, I use brass ferrule, at the RD.

Make sure der hanger is straight and the inner wire is routed correctly at the RD fixing bolt.

There is a spacer in 11s cogsets that sometimes breaks, make sure it ain't.

[summilux]

thanks for that. Cables are campy, no ferrules at lever, and routed behind. RD hanger looks straight. I've re-tensioned the cable. Maybe there was a bit of slack in there. If that doesn't work, I'll check the cuts, maybe there's some blockage in there.

[Joachim]

RD hanger looks straight.

Have it measured, looks straight can be far from straight.

[Black Dog]

Check the adjustment of the tension of the RD cage. It is the screw under the derailleur where the cage attaches that regulates this. This can have a profound impact on shift quality.

[summilux]

That one I know is good. It's more or less the 7mm speced in the instructions.

[Ralph]

My experience about issues like yours is.....after taking care of the obvious things.....housing cut correctly, routed correctly, stuff like that.....the problem can usually be fixed by returning to basics. After releasing all tension on the shift cable, make sure the RD stops are correct over the rear cogs for both small cog and big cog. Then take out all the slack with the barrel adjuster, and fine tune with that. But first go back to basics. You can't tune it up and down the cassette with the cable adjuster, if the stops aren't perfect. You may have to put stop on small cog slightly off cog center toward frame. Good luck. I bet you get it figured out.

[Dave]

Cable friction is often the problem. The shifts to larger cogs should never be a problem, but the shifts to smaller cogs may hesitate, even with the proper cable tension. You can adjust the tension all day and the shifting will never be good in both directions. You have to eliminate the excessive friction.