When to replace bike tires

The rule

A rear road tyre typically lasts about 3,000 km (1,900 miles) for a race tyre and about 5,000 km (3,100 miles) for an all-round tyre. Front tyres last much longer, about 1.7 times the rear in this calculator, because the front carries less weight and does not drive the bike. Whatever the distance, replace any bike tire with visible casing threads, a worn-through wear indicator, a flat, squared-off centre or deep cuts.

The kilometre figures are LeCoach rules of thumb, not manufacturer data. Real tyre life varies a lot with rubber compound, rider weight, road surface, braking style and pressure. Two riders on the same tyre can get very different mileage. This calculator is one of the free LeCoach cycling calculators.

Riders of 90 kg or more, and anyone riding mostly rough roads or trails, should expect less.

The signs: how to check

Kilometres tell you when to look closely. These checks tell you when to replace.

• Wear indicator holes gone. Many road tyres have small holes or dimples in the tread. When they disappear, the tyre is done. This is a hard sign.
• Visible casing threads. If you can see fabric through the rubber, replace the tyre now. This is also a hard sign.
• Flat, squared-off centre. Look at the rear tyre from behind. A flat strip down the middle means the tread is thin and the profile has changed, which affects cornering.
• Cuts deeper than 1 mm or that open when you squeeze. Deflate slightly and pinch the tyre around any cut. If it opens up, the casing may be damaged.
• Frequent punctures. Thin rubber lets more glass and flints through.
• Cracked, dry rubber (age 4+ years). Old rubber hardens and cracks, even on a bike that has hardly been ridden.

On gravel and MTB tyres, look at the knobs. Rounded, torn or missing knobs on the centre or shoulder mean less grip, even if the casing is fine.

Check your tyres every 1,000 km or once a month, and after any ride on broken glass or sharp gravel.

Estimate yours

• Kilometres on this tyre. Count from when you fitted it.
• Wheel. Rear or front. The front estimate is 1.7 times the rear.
• Tyre type. Sets the rear starting point from the table above.
• Rider weight. At 90 kg or more, the estimate drops by 15 %.
• Rough roads or trails. Cuts the estimate by 20 %.

Under 80 % used is "Fine for now", 80 to 100 % is "Check it soon" and 100 % or more, or any hard sign, is "Replace it". Two or more other signs also move the verdict to "Check it soon".

Front versus rear

The rear tyre carries most of your weight and transmits all your power, so it wears faster and squares off in the middle. The front wears slowly but matters more for grip in corners and under braking.

With the front lasting about 1.7 times as long, you will replace the rear more often. Some riders move the front to the rear when the rear is done and fit the new tyre on the front. Either way, check the front for age and cuts, not only for tread. A tyre that has done few kilometres can still be past its best after several years.

Common mistakes

• Waiting for a puncture. Thin tyres puncture on the worst day. Replace at the signs.
• Only checking the rear. Front tyres age and cut too.
• Ignoring sealant. On tubeless setups, sealant dries out over time; Stan's NoTubes says its sealant performs for about 2 to 7 months, less in dry climates.
• Wrong pressure. Too low causes pinch flats and rim damage; too high reduces grip. Use the bike tire pressure calculator.
• Skidding. Locking the rear wheel can wear a flat spot in one stop.

When the estimate changes

• Heavier riders and loaded bikes wear tyres faster.
• Rough roads, gravel and trails wear tread and cut casings.
• Hot weather and rough tarmac wear soft race compounds quickly.
• Training on a smart trainer with the wheel on wears a rear tyre fast. Use a trainer-specific tyre or keep a spare wheel.
• Before a big event, fit fresh tyres a few rides before, not on race morning. Add it to your race day checklist.

Keep brakes in step with tyres using when to replace brake pads and the bike maintenance schedule. Ask LeCoach how to pace and fuel your next event, and it answers from your own rides and goals.