Symptom
Why your gears skip when you push hard
Skipping gears frustrate riders more than almost any other fault, partly because the obvious suspect is usually innocent. The derailleur gets the blame; the chain is normally the culprit.
The single most useful test is when it skips. If it only happens when you stand on the pedals or pull away from a light, that is drivetrain wear. If it skips regardless of effort, or refuses to reach certain gears at all, that is adjustment — cable tension, limits, or a bent hanger.
Chain wear is measurable, not a matter of opinion. A chain checker costs very little and tells you in seconds whether you are looking at a chain job or a chain-and-cassette job, and the difference between those two is significant. Anyone quoting for skipping gears without measuring the chain first is guessing.
What usually causes it
Listed most likely first. Work down the list — the top one is right more often than not.
Stretched chain, worn cassette
How to tell: Skipping happens only under power, usually in the gears you use most. A new chain on a worn cassette skips immediately and constantly.
The fix: Chain measured for wear. If it is past 0.75% it is replaced. If it has been ridden well past that, the cassette has worn to match and both go together.
Gear set replacementAED 135
Cable stretch or a dirty cable housing
How to tell: Shifting got gradually worse over weeks. It hesitates going up the cassette but drops down fine, and a half-turn of the barrel adjuster briefly helps.
The fix: Gear cable re-tensioned and indexed. If the housing is full of sand, cable and housing are replaced.
Gear indexingAED 45
Bent derailleur hanger
How to tell: Shifting is poor across the whole cassette and worse at one end. Usually follows the bike falling over or being packed for a flight.
The fix: Hanger straightened with an alignment gauge, or replaced. Indexing afterwards will not hold until the hanger is true.
Gear indexingAED 45
Limit screws set wrong
How to tell: The chain will not reach the largest or smallest sprocket, or tries to go past it into the spokes.
The fix: High and low limits reset. Quick, and often what is actually wrong on a bike that has just been assembled.
Gear indexingAED 45
Worn jockey wheels
How to tell: Teeth on the small derailleur pulleys look pointed rather than square. Common on high-mileage bikes that have never had them changed.
The fix: Jockey wheels replaced. Cheap, and often overlooked on a bike that has had everything else done.
Worth knowing: Skipping under load is worth fixing quickly — a chain that jumps while you are standing on the pedals is how riders come off. If it happens on a climb or at a junction, stop using that gear until it is sorted.
Not sure which one it is?
Send a photo or a short description and we will tell you the likely cause and the price before anyone travels.
Get a price on WhatsAppCommon questions
Can I just replace the chain?
If the chain is caught early, yes. Past roughly 0.75% elongation the cassette has worn into the old chain's spacing, and a new chain will skip on it straight away. That is why we measure chain wear before quoting rather than after fitting.
Why does it only skip when I pedal hard?
Light pedalling does not put enough force on the chain to make it climb the worn teeth. Load is what exposes the wear, which is why the problem shows up on hills and at traffic lights first.
How long should a chain last in Dubai?
Less than the manufacturer's figure, in our experience — sand is abrasive and accelerates wear on the drivetrain. We are measuring this properly across our own customers' bikes rather than repeating a number from a European catalogue.