SKS Airspy SV

If you're obsessed with tyre pressures, the SKS Airspy SV is your dream widget. It's a pair of electronic pressure sensors that fit over your valves and tell your phone or Garmin bike computer your tyre pressure to within 0.1psi.

The widgets themselves use Bluetooth to transmit tyre pressure data to an app – SKS MyBike – on your phone and ANT+ to send it to a Garmin device. The readings tally closely with those from a standalone gauge and various track pumps and inflators, but I'm a bit dubious about the 0.1psi precision. Seems optimistic, and even if Airspy achieves it, does anyone really need to know their tyre pressure that precisely? (We have a feature on how to choose the best bike tyre pressure if you're not sure what would work for you.)

> Buy now: SKS Airspy SV for £70.99 from Bike Inn

I found the Airspies generally easy and quick to use with my iPhone, but I did see them fail to connect to my Garmin Edge 1030 Plus from time to time. And it took quite a bit of faffing around to figure out how to set up the Garmin app. It's not covered in much detail by SKS's instructions or videos; they really need updating.

Installing the Airspies was very straightforward. You unscrew the tiny locknuts at the top of your valves, screw the Airspy valves into place, push the electronics pod down over the valve and hold the whole thing together with a knurled locknut. Optional 'anti-theft brackets' can be fitted between the Airspy and the nearest spoke, but I really didn't see the point. They might slow a thief down by a second or two, if that, and I found that if they pulled the Airspy to one side at all, they stopped it from working.

You then install the SKS/Mybike phone app if you don't already have it, and set it looking for Airspies to pair with and voila! your phone displays your tyre pressure.

If that weren't giddily exciting enough, there's a Connect IQ data field so you can display tyre pressure on a Garmin device that supports Connect IQ, which is pretty much all recent Garmins.

To connect the Airspies to your Garmin device, you use the Garmin Connect phone app to tell the Airspy Connect IQ app what to look for, by feeding it the serial numbers of the Airspy units from the Airspy app.

The process is barely mentioned in the manual. For an Android phone you follow these instructions and for an iPhone you use these.

Should you?

All right, I can hear you asking, this is all very clever, but what do you actually DO with that information? I thought the same thing. Surely this is a case of not stopping to ask yourself if you could, but whether you should.

I've come up with a few use cases in my time with the Airspies.

Use case 1: Is that really a puncture? You know that nagging feeling that your rear tyre is soft, but you're initially not sure whether it's losing air or you're just having a bad day? Airspy to the rescue with a warning that your tyre pressure has dropped.

You set this up through the Garmin Connect app on your phone where you can set the target pressure for your tyre and the maximum difference from that you'll accept. Set the pressure at 70psi and the difference at 5psi and you get a loud alarm on your Garmin if the pressure drops below 65psi, confirming that you're not just being a bit crap, you do have a puncture, and you should stop and fix it before your expensive carbon rim starts bouncing off the ground.

These settings are quite well buried in Garmin Connect. To find them you go to: More > Connect IQ Store > Manage Device > My Data Fields > SKS AIRSPY > Settings.

Use case 2: Do I need to pump up my tyres? You know, yeah, you probably do, unless you pumped them up, like, yesterday. But if you're not sure, you can check them from your phone or if they've dropped too far you'll get a warning from your Garmin device too. I don't use latex tubes, but for folks that do I can see Airspy being a useful reminder when they've lost pressure.

Use case 3: What's the best tyre pressure for my local gravel riding? With the Airspies in place you can start off at a silly high pressure and gradually lower it until you find the pressure that gives you the best compromise of grip, comfort, speed and not getting pinch flats. This is where the mad scientist possibilities of the Airspies emerge, though I'm reminded of something we used to say when mountain bike suspension began to get super-sophisticated and adjustable: with on-the-fly adjustment you can be sure your settings are always wrong.

Rivals

The only other similar device I'm aware of is the SRAM Quarq TyreWiz. TyreWiz has built-in LED lights to tell you if your tyre's not at the right pressure, so can be used without app or bike computer, but it only works with tubes that have removable cores, and a pair costs £253. That makes £110 for Airspies look like a bargain.

There have also been Kickstarter projects that aim to do much the same thing. BTPS didn't reach its funding target, and two recent ones, PSIcle and Smart iPump have hit target but aren't yet shipping.

Who should buy SKS Airspy?

Mad scientists and tyre obsessives, mostly. The Venn diagram of those categories probably encompasses time triallists and some ultradistance and gravel racers looking to nail the balance of pros and cons of different tyre pressures.

Verdict

Effective tyre pressure-monitoring widget with potentially handy low-pressure alert