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I bought brand new Shimano ST-EF29 (3x8 Speed) Shifter + Brake Lever (both left and right) for my MTB which I installed some 3 months ago. But it is very noisy (especially when shifting from 3rd to 2nd chainring on the left shifter).

It changes super smooth and beautifully quiet from 1st to 2nd speed (chainring), a litle bit harder from 2nd to 3rd speed (chainring) but still satisfactory. The chain is not touching the front derailleur cage at 1x1 Speed and also not touching it at 3x8 speed).

But the noise is quite loud and annoying when shifting backwards from 3rd to 2nd and then from 2nd to 1st speed (chainring).

I noticed a small screw with the spring on the bottom side of the shifter and checked Shimano Tech website. It is called Reach Adjusting Screw and Spring (see photo). But it seems this screw is for brake lever adjustment so I didn't touch it at all.

Reach Adjusting Screw and Spring

Is there a way to fix this? Is there a screw on the shifter/brake lever that needs to be adjusted? The cable tension seems right when changing from 1st to 2nd speed but when changing from 2nd speed to 3rd speed it is a bit hard. The thing is that when shifter is in 1st speed (smallest chainring) the cable is completely loose) so I am not sure if loosening a cable tension (at front derailleur) furthermore would cause shifting problems.

The right shifter (Speeds 1x8) is working perfectly.

I have no clue how to solve this. At first I thought it's because the shifter is new so it will become better/quieter with the time but it is 3 months already and the noise is the same.

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My initial suspicions would be either the indexing is slightly too far outboard, so that the cage is not quite moving far enough to push the chain positively down to the smaller rings; or friction on the shift cable within the housing is delaying or impeding the inboard movement of the cage on downshifts.

Try adjusting the indexing. Front derailleur adjustment is a bit tricky so I always follow Park Tool's front derailleur process.

Check the shift cable is running freely. Detach the cable from the derailleur, pull on it to provide so tension and work the shifter, the cable should pay out easily and smoothly on downshifts.

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I would be checking the setting for the high limit screw in particular, while following a front derailleur set up process. (make sure the rear derailleur is indexed correctly before working on a front derailleur)

The reason is that you report the shifting from 2 to 3 being a bit harder than the shift from 1 to 2. I find that if the limit screw is just a smidge tight, it is this limit that you are pushing against to reach 3. Then when you push the downshift to release the cable tension, the cable has to pull against the limit screw initially which creates a noisier clunk as the extra tension releases.

If the shifting is otherwise good, perhaps loosen the h screw just a fraction, 1/8 to 1/4 of a turn. Remember what you do because if it doesn't help, you can always tighten it back again.

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As Argenti surmised, it is likely an indexing issue with your front derailleur, and going through the process like you're just putting the front derailleur on the bike for the first time is the best way to discover and solve the problem as well as develop experience with a bicycle system. Start at the beginning. It's good that your rear system is working well and properly as this is a prerequisite to the indexing the front system.

Here are the shop instructions from Shimano for the front drive System that includes the ST-EF29. Note the troubleshooting tips at the end of front derailleur install instructions. Though one of these tips may solve the problem, these assume one is at the point of correct install and cable connection to the pinch bolt, so do start at the beginning.

A few things I like to offer up regarding the front shifting system are 1) position the front derailleur so that the derailleur's outside cage plate is parallel to the large chainring, and the closer to the teeth you can get (without interfering) the crisper your shifting will be. 2) pay special attention to the cable routing, especially very near and at the pinch bolt. Many systems utilize a leverage tab the cable must be routed over for the proper force to be applied to affect movement of the derailleur. A very small change in the way the cable is secured and therefore the line of force being applied to move the cage can mess up the shift.

Lastly, I'll point out that cable tension is altered with the turning of the in line barrel adjuster, located where the cable leaves the shifter body in the ST-EF29. Counter- clockwise will tighten the cable and helping to move the chain to a larger chainring. Clockwise movement of the barrel adjuster lessens cable tension, allowing a better cage-chain line up, quieting noise and easing shifts to small ring.

  • Thanks guys a lot for all your answers! They all seem logical to me so I hope to solve this problem tomorrow if weather permits. I will go through your suggestions, one by one, and I believe this will help to get rid of the annoying noise and make my system work properly. Your help is super appreciated. Thank you very much! – C. Felipe Aug 1 at 19:10

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