Mountain Biking and Mountain Bikes for Africa









Mountain Bike Gear Shifting Problems


Mountain bike gears are a critical part of the bike, they work the hardest and are one of the main reasons why mountain bikes can go where they do. Poor gear shifting and mis-shifts are probably the biggest bike maintenance issue that you will find. Understanding how and why you can have gear shifting problems will help to prevent them. Contrary to popular belief adjustments are not always the solution to these problems. Higher quality components like Shimano LX, XT and XTR should provide trouble free shifting with virtually no adjustments required after correct setup. Lower quality components will not provide as smooth or reliable shifting and may require more regular adjustment.

If your gears have never worked properly from the start then they probably have not been setup properly. If you had your gears setup properly and they worked faultlessly for a period of time only to discover that now things are not working properly anymore then you can be sure that something has changed. In this case slight cable tension adjustments, a couple of quarter turns, should be all that is required to correct a mis-shift. If this does not correct the problem and you end up making major adjustments then there is something else wrong.


Gear Shifting Problems

Bent derailleur hanger this is a common problem where transportation, a fall or a knock on your derailleur can cause your derailleur hanger to become bent. All of a sudden some of the gears will not be working properly. Best solution is to replace the hanger, they are designed as replaceable parts, bending it straight is a temporary solution and will not solve the shifting problems.

Worn chain and or cassette mis-shifts under pedalling tension when pedalling hard or when the drivetrain is dirty are typical symptoms. Check the chain length and condition of the cassette teeth, if either of these are worn they can affect shifting. Ideally the two should be in sync from a wear point of view, so often replacing both is the best option if either is badly worn.

Dirty, rusty or old cables this is also a common problem, symptoms are lazy shifts where the chain shifts slowly either up or down. It is noticeable when the shifter is hard to operate and when there is a noticeable delay in shifting after clicking the shifter. If in doubt replace the cables, more often than not it will make a difference and make your bike feel much better.

Low cable tension Symptoms are a lazy first shift or an incomplete last shift. This is easy to detect, when the cable is all the way out (in the high position) with no tension and it is loose and touching the frame, then there is a lack of cable tension. Just tighten the barrel adjuster (turn out or anticlockwise) to take up the cable slack and the problem should be solved.

Ghost shifting - This happens on full suspension bikes where the last section of cable between the frame and the derailleur is too short. As the suspension moves, usually at full compression, the cable is tensioned and initiates a shift. Other problems related to changing chain tension on some full suspension bikes can also affect shifting. So just bear these in mind if you encounter unexplained shifting problems. Sometimes setting up gears of a full suspension bike on a work stand may not be the same as setup on a bike under load.

Gear Setup and Adjusting
Gear and Brake Cable Fitting

Check out our Mountain Bike Maintenance and Repair Guide for the next step in maintaining your bike. Join our mailing list and we will let you know when we update this section



Buy and Sell
Mountain Bikes

mountain bikes for sale
buy online now.....


Zinn and the Art of Mountain Bike Maintenance
bike maintenance books

...order online... 

home | search | contact usAdvertise on MtbOnline
MtbOnline is owned and run by mountain bikers. The views expressed are not necessarily those of MtbOnline.
We provide all the information in good faith and accept no responsibility for the accuracy thereof.
All rights reserved 2006-2012 MtbOnline - Mountain Biking in South Africa