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-   -   SRAM Force 22 rear derailleur – questions (https://www.bikeforums.net/bicycle-mechanics/1032045-sram-force-22-rear-derailleur-questions.html)

 Redbullet 09-26-15 03:08 PM

SRAM Force 22 rear derailleur – questions

Hello,

I noted I can usually shift up 1, 2 or 3 cogs at once with SRAM Force 22, depending on how much I move the shifter, but the questions are:

1. If I start from the smallest cog (11) and move the shifter full range, then it switches 4 cogs at once (from 11 to 15, for around 80% of cases), or it makes a 3 cogs shifting with failure (from 11 to 14, but unsuccessfully trying to lift the chain to the 15th cog, for around 20% of cases). Is this normal?

2. When shifting only one cog at once, I noted that I can solve the failures at the middle of the range (14 – 15 cogs) by tightening the cable. However: when should I stop tightening the cable? What are the symptoms of a too tighten cable for the rear derailleur?

3. Overall, in practice, what would be the average failure rate of a well tuned SRAM Force 22 rear derailleur? Is a rate around 5-10% acceptable?

R.

 alcjphil 09-26-15 04:30 PM

Originally Posted by Redbullet (Post 18196382)
Hello,

I noted I can usually shift up 1, 2 or 3 cogs at once with SRAM Force 22, depending on how much I move the shifter, but the questions are:

1. If I start from the smallest cog (11) and move the shifter full range, then it switches 4 cogs at once (from 11 to 15, for around 80% of cases), or it makes a 3 cogs shifting with failure (from 11 to 14, but unsuccessfully trying to lift the chain to the 15th cog, for around 20% of cases). Is this normal?

2. When shifting only one cog at once, I noted that I can solve the failures at the middle of the range (14 – 15 cogs) by tightening the cable. However: when should I stop tightening the cable? What are the symptoms of a too tighten cable for the rear derailleur?

3. Overall, in practice, what would be the average failure rate of a well tuned SRAM Force 22 rear derailleur? Is a rate around 5-10% acceptable?

R.

The "failure" is in the shifter, not the derailleur. The derailleur is stupid, it only does what the shifter tells it to. The shifter's instructions reflect the action of the user. If the user doesn't push the shift lever quite as far one time as he/she did the previous time, the result may be different

 Redbullet 09-26-15 04:53 PM

Originally Posted by alcjphil (Post 18196575)
The "failure" is in the shifter, not the derailleur. The derailleur is stupid, it only does what the shifter tells it to. The shifter's instructions reflect the action of the user. If the user doesn't push the shift lever quite as far one time as he/she did the previous time, the result may be different

Thanks.

Yes, I agree, but only in a certain degree. This is not a "free" shifting mechanism, as we used 30 years ago when we had to manually adjust the accurate position of the shifter / derailleur. It is a clever indexing device.

If I move it to maximum starting from the 11 teeth cog, it makes one supplementary "click" and it jumps 4 cogs (or sometimes - 20% - fails). If I move it to maximum starting from any other cog above 11 teeth, it makes one less "click" and it jumps 3 cogs, as written in the manual. It looks to me somehow inconsistent, so I suspect a wrong setting that I can not identify.

As about the tension of the cable - I assume that there is a maximum that I should not exceed, but I can not identify it. Low tension leads to failures in shifting to the mid range - 14 - 15 teeth cogs. So, I increase the tension in the cable, but how much? Maybe I go too far and this creates other type of failures? How can I identify the right tension of the cable?

 alcjphil 09-26-15 04:59 PM

Originally Posted by Redbullet (Post 18196622)
Thanks.

Yes, I agree, but only in a certain degree. This is not a "free" shifting mechanism, as we used 30 years ago when we had to manually adjust the accurate position of the shifter / derailleur. It is a clever indexing device.

If I move it to maximum starting from the 11 teeth cog, it makes one supplementary "click" and it jumps 4 cogs (or sometimes - 20% - fails). If I move it to maximum starting from any other cog above 11 teeth, it makes one less "click" and it jumps 3 cogs, as written in the manual. It looks to me somehow inconsistent, so I suspect a wrong setting that I can not identify.

As about the tension of the cable - I assume that there is a maximum that I should not exceed, but I can not identify it. Low tension leads to failures in shifting to the mid range - 14 - 15 teeth cogs. So, I increase the tension in the cable, but how much? Maybe I go too far and this creates other type of failures? How can I identify the right tension of the cable?

The derailleur still has nothing to do with what happens. It is all about the shifter

 Redbullet 09-26-15 05:14 PM

Yes, it could be the shifter. Maybe some imperfect setting. That's what I'm investigating. It might some kind of little tightening / loosening of a screw, but I don't know how to find it. It is not critical - I can always fix it by re-shifting when it happens, but I like things working as written in the manuals...

 alcjphil 09-26-15 05:22 PM

Originally Posted by Redbullet (Post 18196652)
Yes, it could be the shifter. Maybe some imperfect setting. That's what I'm investigating. It might some kind of little tightening / loosening of a screw, but I don't know how to find it. It is not critical - I can always fix it by re-shifting when it happens, but I like things working as written in the manuals...

There are no settings on shifters. There are no screws that you can turn to change things. If you don't like what happens when you shift, talk to the dealer who sold the bike, or send an Email to SRAM. they are very sensitive to listening to customers. Consumer testing is the way they fix problems. Who knows? you may help next year's TDF winner

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