Why Won't My Bike Gears Change Properly — The Two Minute Checks First: Questions Answered

Bike Care at Home
Bike Care Answers Team

If your gears won’t change properly, the parent article promises a set of checks you can run in under two minutes each. This page is organised in the order a rider should try them — starting with the fastest and most likely fix first — before listing the full question list below.

Why won’t my gears jump to the next gear when I click the shifter?

The derailleur might not be pulling the cable enough to move the mechanism, or the cable could be sticking inside the housing due to grit or corrosion[1]. You should first check if the cable is running freely and then look at the barrel adjuster to fine-tune the tension. Full details in our guide to How To Adjust Bike Gear Cables At Home — Barrel Adjuster And Cable Tension .

My chain keeps falling off the back sprocket when I pedal hard.

This is often caused by a bent derailleur hanger which throws off the alignment of the derailleur relative to the cassette[2]. Check the hanger for any signs of bending before you try adjusting the cable tension, as tweaking the cable won’t fix a misaligned frame. Full details in our guide to Why Won’t My Bike Gears Change Properly — The Two Minute Checks First .

The gears are skipping when I put power down on a hill.

Skipping under load usually indicates that the cassette teeth have worn down or the chain has stretched, creating a mismatch between the two components[3]. Inspect the chain for wear and check the cassette to see if the teeth have developed a hook shape. Full details in our guide to Bike Gears Skipping Under Load — Cassette Wear, Chain Stretch Or Cable Tension .

How do I turn the barrel adjuster to fix my gears?

You turn the barrel adjuster to lengthen or shorten the cable housing, which changes the amount of pull the derailleur receives and allows you to fine-tune the gear indexing[1]. It is important to turn it in the right direction to add or remove slack, so you don’t make the problem worse. Full details in our guide to How To Adjust Bike Gear Cables At Home — Barrel Adjuster And Cable Tension .

Is it normal for my gears to make a clicking noise?

A clicking noise can be caused by a sticking cable, a worn chain, or simply the derailleur moving into the next cog, but it is often a sign that the cable tension needs adjusting[4]. Try adjusting the barrel adjuster to see if the clicking stops, as the cable might be binding slightly. Full details in our guide to How To Adjust Bike Gear Cables At Home — Barrel Adjuster And Cable Tension .

Can I fix gear problems without taking the bike to a shop?

Many common gear issues, such as adjusting cable tension or checking for a bent hanger, can be resolved at home with basic tools and a little patience[5]. You can often diagnose the problem yourself by ruling out worn parts or contamination before deciding to visit a mechanic. Full details in our guide to Why Won’t My Bike Gears Change Properly — The Two Minute Checks First .

What is a derailleur hanger and why does it break?

The derailleur hanger is a small piece of metal bolted to the frame that holds the rear derailleur in the correct position, designed to bend before the frame itself does[2]. If you crash or knock the bike, this hanger can bend slightly, which throws off the alignment of the gears[2]. Full details in our guide to Why Won’t My Bike Gears Change Properly — The Two Minute Checks First .

Why does my chain jump two gears at once?

A sudden jump to a completely different gear usually means the derailleur has moved too far or not far enough, which is often a result of a bent hanger or a cable that has stretched[6]. Check the physical alignment of the derailleur and the hanger before attempting to adjust the cable tension. Full details in our guide to Why Won’t My Bike Gears Change Properly — The Two Minute Checks First .

My gears feel stiff and hard to change.

Stiff gears are frequently caused by a cable that has rusted or dirt working its way into the barrel adjuster and the housing, restricting the cable’s movement[5]. Clean the cable and housing and ensure the barrel adjuster is moving freely to restore smooth shifting. Full details in our guide to How To Adjust Bike Gear Cables At Home — Barrel Adjuster And Cable Tension .

Will a new chain fix skipping gears?

A new chain might fix the issue if the skipping is caused by chain stretch, but if the cassette is worn, the new chain will still skip because the teeth are too worn to hold it[3]. Check the cassette for wear after installing a new chain to see if it is the root cause of the problem. Full details in our guide to Bike Gears Skipping Under Load — Cassette Wear, Chain Stretch Or Cable Tension .

How do I know if my derailleur hanger is bent?

You can tell if the hanger is bent if the chain does not sit straight across the cassette or if the derailleur is not parallel to the cogs when the bike is in the middle gear[2]. A simple way to check this is to look for any diagonal movement of the derailleur body as you shift. Full details in our guide to Why Won’t My Bike Gears Change Properly — The Two Minute Checks First .

Why do my gears slip when I sprint?

Sprinting puts more force on the drivetrain, which can expose a worn cassette or a stretched chain that would otherwise hold the gear[3]. If the chain skips under this load, it is a clear sign that the mechanical interface between the chain and cassette is worn. Full details in our guide to Bike Gears Skipping Under Load — Cassette Wear, Chain Stretch Or Cable Tension .

If none of these two-minute checks resolve the problem, the fault is likely mechanical wear rather than adjustment. The next diagnostic step is covered in our guide to gear skipping .

Sources

  1. SRAM service article on rear gear adjustment. https://www.sram.com/en/service/articles/rear-gear-adjustment
  2. BikeRadar advice on derailleur hangers. https://www.bikeradar.com/advice/workshop/derailleur-hangers
  3. Road.cc feature on when to replace chainrings and cassette. https://road.cc/content/feature/when-should-you-replace-your-chainrings-and-cassette-256420
  4. Road.cc feature on how to adjust your rear gears. https://road.cc/content/feature/how-adjust-your-rear-gears-164256
  5. BikeRadar workshop guide on how to adjust bike gears. https://www.bikeradar.com/advice/workshop/how-to-adjust-the-gears-on-your-bike
  6. 331 Racing article on cassette-related issues. https://www.331racing.com/cassette/

Detailed guides: