The leader in transmission is very simple! A little method and precision and everything passes precisely!
To adjust your Shimano indexing, you will only need a 5 mm allen wrench and your hands of course to turn the tension barrel. The best would be to have a support to hold the bike in addition, but you can get out of it by putting the bike on your casseroles and saddle!
Pictures © Frédéric Iehl
Time and difficulty
It will take you 5 to 15 minutes to properly adjust your indexation. It will just depend on the installation of your bike and whether or not to tighten the cables. On the difficulty side, it’s very easy with logic.
The rear derailleur is first placed on the smallest sprocket by lightly pressing the gear shift lever.
If you feel that the cable has a lot of soft, tighten the adjustment barrel thoroughly. Then loosen it by two turns.
Now we will have to stretch the cable. To do this, we loosen the bolt slightly. We extend the cable by hand and tighten.
We are always on the smallest sprocket. We press the climbing lever to reach the second.
If nothing happens or the chain goes up in half…
… We turn the tension barrel in this direction, a quarter turn per quarter turn, continuing to pedal and until the pinion passes.
If, on the contrary, the chain tends to get the third pinion…
… We will relax the cable by turning the adjustment barrel in this direction a quarter turn by a quarter turn. Until silence is obtained!
The chain must be perfectly « centered » on the second sprocket. Visually, it is sometimes difficult to decide, but in the ear it gets along very well! Silence is the guarantor of a good adjustment.
All that remains is to test the 11 gears of the Shimano indexing to ensure that all the speeds pass. Precisely and silently. We stay at least 5 seconds per pinion to be of course!
We lightly press the left lever to go down to the small chainring.
By pedaling, we then press the climbing lever to pass on the large chainring.
If the chain is struggling to mount, the cable will have to be tightened.
You will have to press the downlever while pedaling to put the chain back on the small chainring. It will be necessary to tighten the cable. Two possibilities: either there is a adjustment barrel somewhere, or the cable is retained at the derailleur. This is our favorite solution.
The cable clamping bolt must be slightly loosened and pulled firmly to tighten it. It is tightened properly once the right tension is obtained.
By pedaling, the platform climb lever is pressed again.
The chain must then pass on the large set. And it must be silent!
The Shimano indexation of the chainrings rarely moves when it has been properly adjusted. So you won’t have to do this manipulation often. This is less true for the rear derailleur. Transport, wheel changes but also the settlement of the ducts will require you to review the indexing setting several times in the season. But there is no need to touch up at the tension of the cable, a quarter turn up or down should be enough.