Different types of tyres are suited to different bikes, different terrains and different weather conditions. But one thing they all have in common is the owner’s obligation to keep the tread depth on the tyre within the legal limits. Failure to do so will result in an instant MOT fail, but more worryingly will make your bike unsafe and could potentially cause you to be involved in an accident or suffer injury.
Your tyres are one of the most important parts of your bike and you must ensure that they are safe and legal every time you go out on the road.
What Is Motorcycle Tyre Tread Depth?
The tread of a tyre refers to the rubber on its circumference that makes contact with the road or the ground. The ‘tread’ is the rubber that sits above the grooves on the tyre’s surface. The difference in height between the bottom of the groove and the top of the tread is known as the tread depth. As tyres are used, the tread starts to wear off, limiting its effectiveness in providing traction. When the tread has worn away completely, this is known as a bald tyre.
What Is The Legal Requirement For Tyre Tread Depth?
Here in the UK, the legal requirement is that the tyre tread depth is no less than 1.0mm around the circumference of the middle three-quarters of the tyre.
Once your tyre reaches this limit, it must be replaced. It is advisable though, to replace tyres before they reach their legal limit, as their ability to provide traction will be heavily compromised.
Many organisations and companies advise changing at 2.5mm tread depth because at lower than this tread depth, you will notice a decline in your motorbike’s handling ability and stopping distance.
Riding around on tyres with a lower tread depth also makes you more susceptible to punctures, nasty loose nails and other damage to the tyres as they are wearing paper thin.
According to the 1988 Road Traffic Act, it is not legal for a vehicle that isn’t road-worthy to be used on a public highway. Tyres that are below the 1.6mm legal limit are classed as illegal. The penalty for bald tyres can be severe: as much as a £2,500 fine and 3-penalty points on your driving licence for each worn tyre.
Fortunately, as bikers we’re more aware than car drivers of the condition of our vehicles and pay more attention to things like tyre wear as it dramatically affects how the bike handles. So the chances of being caught with bald tyres on your motorcycle are slim to none if you pay them the slightest attention from time to time..
How Do I Measure My Tyre Tread Depth?
Most often, you will be able to tell by looking at your tyres that they are a bit knackered. But if you are unsure, there are more sophisticated measuring tools available.
Tyre tread wear indicators on the tyres themselves should give you a good indication of the condition of the tyre. If the tyre is flush with these, it is below the legal limit and will need replacing.
Mechanics will also use a tyre or tread depth gauge, which will measure the amount of tread wear left.
Making sure your tyres have the correct amount of tread on them is not just an important legal requirement, it can also significantly affect the handling of your bike and will make your bike safer on every journey.