Decode tyre markings HOWTO NEW NEXTBASE CAM PLAYS IT SMART

Nextbase iQ smart dash cam Price: Under £500 Contact: nextbase co uk

NEXTBASE has been teasing more details about its next generation of dash cam, which promises greater in-car security and driver assistance.

We last covered the iQ a year ago (Issue 1,710), but its planned launch date and price have altered since then The August 2022 delivery has moved to this spring and its £300 cost is now said to be “under £500”.

Perhaps the delay is understandable because the iQ aims to deliver much more than just capturing your drive and the behaviour of other road users. A GPSbacked, three-cam IR system remains at the heart of the device, but delivering 4K front and 1440p rear and cabin views at all times. AI technology provides real-time monitoring of other vehicle’s speeds and trajectories, while driver-aware functions combat drowsy or distracted driving.

A vehicle-aware function monitors vehicles and pedestrians and provides driver alerts, plus it retains the Series 2 cam’s ability to automatically alert the emergency services following a serious accident. The spatial monitoring and alerts also work when the car is parked Key is the 3G and 4G connection, so activity can be monitored from anywhere, and it sends alerts if there’s an incident.

What do they mean?

THE days of ringing round tyre depots looking for the best prices have long gone and most of us now do our searching online But you need to know what you are looking for

Some online tyre retailers let you search using your car’s registration number But it pays to check what tyres you have fitted, because they may have been changed, or the maker offered several size options

Knowing the correct specification you need may also increase the choice on offer to you, because the speed and load ratings on your tyres will be the minimum you can fit Higher-spec tyres are also an option

The key figures are usually the biggest on the sidewall and follow this format: 215/55 ZR17 94W The first figures are the width in millimetres, and the next pair is the profile or aspect ratio. This is a percentage of the width and shows the tyre’s height – 55 per cent of 215mm in our example

The letters indicate the type of construction – in our example it’s R for radial, by far the most common type, and the Z shows it is designed for more than 149mph. The next number is the wheel size in inches The 94 is the load index, and the letter (W) the speed rating – up to 168mph in our example These are the minimum required and don’t relate to use or the car’s performance.

Other markings to look out for are those that indicate the tyre has been optimised for a particular car maker Most major manufacturers have their own markings –usually two or three letters such as Audi’s AO, although BMW uses a star and VW a plus sign in a circle Check your car maker’s mark, and while it’s not compulsory to fit OE spec, it can be highly desirable for some models

If you want run-flat tyres, there is no industry standard, with each maker using its own two or three-letter mark Just check when you have chosen the brand you want Finally, when assessing used tyres, look for the production date: four numbers, usually in a panel. The first two are the production week and the second pair the year Replace anything more than five or six years old