# SRAM Rival, drivetrain noise in the middle gears?



## taki5

i am a Rival newbie and had some questions. I can cross chain big ring in front, big ring (50/34) in back (12-25) without any significant chain noise (i know this is a no-no)...similarly, i can cross chain the other way with mostly no noise....but...if im in the big ring in front and on the 17/19/21 cogs in back, there is significant noise compared to some of the other cogs. if i stop pedalling and just coast, the noise stops. there is a distinct sound related to each cog, meaning, the noise is not the same with each 17/19/21 cog.

Here is an explanation of the noises: on one cog, the noise is a rattling noise during pedalling. on the next cog, the noise is a repetetive noise (i suspect, the SRAM powerlock connector?) but otherwise quiet, on the other cog, the noise is a bit of a combination of the two, but generally not as loud.

rear cassette is PG 1070, chain is SRAM PC 1071, Rival FD and RD. components have 20 miles on them.

any ideas? it seems to shift ok, although, when i want to shift to a larger cog in back, it occasionally goes to the bigger cog and then immediately jumps back down.


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## Daren

Does the chain also only have 20 miles on it?


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## taki5

yep, its an all new drivetrain.


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## asad137

taki5 said:


> any ideas? it seems to shift ok, although, when i want to shift to a larger cog in back, it occasionally goes to the bigger cog and then immediately jumps back down.


You need to tweak your cable tension with the rear derailleur barrel adjuster. At the ends of the cassette, the RD is sitting against the limit stops, so no funny noises and the derailleur is in the correct position. In between, it's the cable tension that determines derailleur position. If your bike isn't shifting right in the middle cogs, it's almost always a cable tension problem.

Asad


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## taki5

thanks for the suggestion. i will fiddle with it some the next time i get a chance. i did notice that there wasnt much cable tension whatsoever in the "loop" of cable just in front of the RD, but because im not familiar with SRAM yet, i was afraid to add tension to the cable. looks like i need to do some reading on how to adjust.


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## Road Hazard

I'll be interested to hear how this works out.

I've got two 1070 cassettes (a 12-27 and a 11-28), both with 1071 chains. Otherwise Force derailleurs and compact crank. I use them on the same bike but with different wheels.

The 11-28 is quiet and has been since new (about 4000 miles now). The 12-27 has only about 50 miles and it's been making the same sounds you are describing since day one, when the chain is in the middle of the cassette but not the "edges". I'm pretty sure the adjustment is right since shifting is good all the way up and down.

I figured it was not machined as precisely as my other one and maybe it would stop after being broken in a few hundred miles. We'll see. Or maybe the spacers or cassette sections just aren't seated quite right, maybe I'll take it off and try to reseat everything.


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## XR4Ti

I find the power connector is the source of a lot of noise. It is wider and will catch on adjoining cogs in the rear derailleur if the alignment is off. Fine tuning solved it for me.


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## Camilo

Here's a method I've posted a couple of times which really works well for me. It's not my invention, but I can't remember who taught it to me. It sounds a lot more complicated than it actually is. Just read through it and if you think about it, it's really simple and quick. There's other ways to do a real fine tuning, but you might give this a try.
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Here's how to really tune in your index shifting, assuming it has full range small to large (in other words, the high and low stops are adjusted properly and that the derailleur moves from the smallest to the largest cogs with the appropriate number of clicks in the shifter).

This is for when it just isn't shifting crisply. That is generally caused by the cable stretching and/or settling in. It's pretty normal to need to do this after a couple hundred miles after changing the cables, but after that shouldn't be needed hardly at all.

It really only takes a minute. Once you understand what you're doing, it takes about as long as it takes to read the following:

Shift into one of the middle cogs. Doesn't matter which one. Doesn't matter if it's a little noisy at this time.

While pedaling the bike, turn the cable adjuster counterclockwise slowly to cause the derailleur to shift on it's own to one cog larger. In other words, you're not doing anything with the shifter, just tightening the cable. Stop adjusting as soon as it shifts.

NOTE: if you can't turn the cable adjuster enough to make this happen, you'll need to loosen and re-attach the cable to the rear derailleur to take out some slack. Make sure you do this with the cable adjuster turned almost all the way in (maybe just 2-3 turns out from fully in) so that you have plenty of room to tighten/lengthen it later.

Then, moving the barrel adjuster 1/4 turn at a time the other way - clockwise - turn the adjuster clockwise until it shifts down to the "correct" cog, and keep turning it clockwise until it just shifts onto one cog smaller. Again, stop right when it shifts to that smaller cog. *Count the 1/4 turns while you are doing this*. From the "larger" to the "smaller" cogs it will probably come to something like 15-18 quarter turns, but that number doesn't really matter as long as you count. It's easy to count, because that barrel adjuster at the rear derailleur has detents every 1/4 turn.

Then, turn the adjuster back the other way - counter clockwise - counting your 1/4 turns and *stop at 1/2 the number you counted* when you went from "one cog too big" to "one cog too small". This will cause the derailleur to move back to the "correct" cog, but it will be exactly in the middle of the correct cog, not a little one side or the other. This should give you perfect shifting.


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## bruce_wayne

I tried the technique described by Camilo after reading about it in another one of his posts. Was very happy with the shifting and quieter drivetrain afterwards.


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## Road Hazard

Hm, I've tried the fine tuning (although I note that tuning on the stand does not equal actual tuning with my body weight on the bike, I suspect that my weight on the frame deflects it just enough to thrown the fine tuning off).

I've even tried mis-tuning the rear derailleur just to see if I could get the same klackty noise in the top 3 cogs or bottom 3 cogs, they don't.

I'm more convinced that the upper middle 2 cogs (mostly the 17t but the 19t also) in my 12-27 are just not machined very well. My 11-28 cog has never made this noise even when the derailleur was a bit tight or a bit loose.

I'll just hope that with a few more hundred miles it will quiet down. Or I'll just enjoy the "audible feedback."


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## samh

*shifting problem*



asad137 said:


> You need to tweak your cable tension with the rear derailleur barrel adjuster. At the ends of the cassette, the RD is sitting against the limit stops, so no funny noises and the derailleur is in the correct position. In between, it's the cable tension that determines derailleur position. If your bike isn't shifting right in the middle cogs, it's almost always a cable tension problem.
> 
> Asad


Do same symptoms happen with worn cassette? (ghost-shifting)


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## asad137

samh said:


> Do same symptoms happen with worn cassette? (ghost-shifting)


I don't have personal experience with that, but I would guess no. If the derailleur is aligned properly, even a worn cassette _shouldn't_ ghost shift -- cassette wear shouldn't cause the chain to move sideways. But I could be wrong.

Asad


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## rubbersoul

switch to shimano!


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## Kristatos

Before you do anything else if you're cassette is making noise put a cassette tool/wrench on it and make sure the lockring is tight. If the cassette is loose it will make noise, often it is worse in some gears than others. 

I would also check chainring bolts and make sure there's no play in the BB. 

If all the above checks out, and the rear wheel is seated and QR is tight, then adjust rear derailleur not forgetting the b-screw.


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## qatarbhoy

Camilo said:


> Here's a method I've posted a couple of times which really works well for me. It's not my invention, but I can't remember who taught it to me. It sounds a lot more complicated than it actually is. Just read through it and if you think about it, it's really simple and quick. There's other ways to do a real fine tuning, but you might give this a try...


Well, the noises from the middle cogs on my SRAM-equipped bike were driving me crazy so I gave Camilo's method a go. It'\s easy and it works perfectly, at least as far as I can tell from a quick scoot around the block! No noise... bliss. I will go for a longer ride tomorrow and see if my first impressions were correct.


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