How to Adjust Your Shifting

by Pedal Wrencher

Posted: 2016-05-03 at 21:03

But First – What Are You Adjusting?

First, though, you need to know what you’re adjusting. You’re actually not going to be adjusting your shifters at all. In fact, you’ll be adjusting your derailleurs, which are the actual mechanisms that change gears and allow you to go faster or get up hills more easily. You can actually think of your shifters as the mechanisms that “tell” your derailleurs what to do.

With that in mind, depending on your bike, your derailleurs, and your shifters, you may be doing almost all of your adjusting at the shifter or at the derailleur. We’ll get to that in just a moment.

Cable Tension Governs Shifting

To understand how to adjust your shifting, you first need to understand how your bike shifts gears. Your derailleurs are governed by the tension on your shifter cables. Each of these cables is held in place by a pinch bolt on the derailleur.

When there’s no tension on the cable, the derailleur will move to the position in which its internal springs aren’t under any tension, too. That position will put the derailleur at the smallest gear in the cluster. So, the rear derailleur will naturally shift toward the highest (smallest) gear, and the front derailleur will naturally shift toward the lowest (smallest) chain ring.

As you ride, your cables will stretch, leaving less tension on your derailleurs, and that’s why it suddenly becomes more difficult to shift to easier gears in the back or harder gears in the front when you haven’t adjusted your shifting in a while.

Small Tweaks with the Barrel Adjusters

Rear Barrel Adjuster

The image above shows a rear derailleur’s barrel adjuster and its pinch bolt. If you’re just noticing a little bit of hesitation when you shift to lower gears in the rear, you can make adjustments with the barrel adjuster. This is essentially a spring-loaded nut that takes up tension in the cable. Give it a half-turn to the left, and then try shifting while pedaling. If you’re still noticing hesitation, try another half-turn.

If you suddenly notice that the derailleur is jumping too far when downshifting and getting sluggish when you up shift, you should give it a half-turn back to the right. Make small adjustments until you get smooth shifting in both directions.

Adjusting the front derailleur involves the same process, but the barrel adjusters for most front derailleurs are actually on the shifter or mounted to the cable stops on the down tube. This is the part we mentioned earlier about some differences in what part of the bike you’ll be making adjustments on. Wherever your barrel adjuster is mounted, it will still do the same job and can be treated the same way.

Resetting Your Barrel Adjusters

If you notice that your barrel adjuster is already backed out a good bit, you can reset it for more adjustment. Go ahead and turn it to the right until it doesn’t turn freely anymore, but don’t try to over-tighten it. Then you’ll need a wrench to loosen the pinch bolt (usually a five-millimeter Allen wrench or a ten-millimeter open-end or box-end wrench). Loosen the nut, pull the excess cable through and put tension on it with your hand. Then tighten the nut and adjust the derailleur using the barrel adjusters.

If you are having trouble shifting up and down and/or if shifting to the high or low gear throws your chain into your spokes or in between the frame and your gears, you’ll need a little bit more attention than an adjustment. These are signs that the limit screws have been tampered with or that the derailleur hanger has somehow been bent. They’re also signs that you need to get a pro to look at your bike. Take it to your local bike shop for a professional diagnosis and the right repairs. Most of the time, though, you’ll have no trouble adjusting your shifting on your own using these steps.

Pedal Wrencher

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