For peace of mind when you’re touring in your motorhome it is best to be certain that all your tyre pressures are spot on. Safety and performance, particularly fuel consumption will be improved. So, for those pre-holiday vehicle preparations, do you generally visit a garage to check your tyres? Given that plenty of garages seem to have awkwardly sited or broken air lines, we think it’s well worth investing in a portable tyre compressor that you can use at home and keep on board just in case you need it while you’re away!

So we got a collection of reasonably priced products onto the Practical Motorhome test bench to find out which are the best tyre inflators you can buy.

In this review we’ll look closely at the Ring RAC640 Digital Air Compressor + Inflator & Deflator. It was one of the best tyre compressors we tested and costs £39.99.

The Ring RAC640 was up against some strong contenders, for instance we also tested the Ring RAC630 Digital Compressor & LED Light at £34.99, the Halfords Advanced Rechargable Multi-Purpose Tyre Inflator at £54.99, The Halfords Rapid Digital Tyre Inflator at £34.99 and the cylindrical Ring RAC700 4×4 Air Compressor, costing £41.99. 

It’s not hard to spot that this unit and the winner of our group test – the Advanced Rechargable Multi-Purpose Tyre Inflator from Halfords – are closely related. But the big difference between the two products, which accounts for this one’s considerably lower price, is the lack of an internal battery in the Ring RAC640 Digital Air Compressor + Inflator & Deflator.

Fortunately, the power lead is long enough, at 3m, to ensure that the unit is within reach of a power source regardless of which tyre it’s tackling. It can inflate a flat tyre to 35psi in less than three minutes and can blow up an air bed in 30 seconds.

The pressure gauge has a digital display that is easy to read and you can set it to PSI, bar, kg/cm2 and KPA. You can preset the pressure you need and let it run until the automatic cut-off activates. There’s a short video on the Ring website that shows how to use a Ring air compressor to inflate a tyre. It also shows the steady beam of the built-in white torch light in action, along with the red light setting, which can flash regularly to act as a general warning light, or flash the red SOS signal in Morse code.  

The kit includes a storage case, so that you won’t lose the attachments. There’s a tyre deflation valve, too, which can be handy if you’ve accidentally put the wrong tyre pressure figure in for the load.

It weighs 1.847kg and measures 280mm high, 270mm wide and 125mm deep, which shouldn’t be too much of a problem to fit into a motorhome locker. 

Power source aside, this and the winning Halfords tyre compressor are basically the same. Both are quick, accurate, and boast auto-stop, plus a leisure inflator/deflator. The latter consists of a handy six-piece adapter kit so that you can easily inflate your bicycle tyres, air beds, footballs and other toys and leisure inflatables.