Pro Bike Tool CO2 Inflator

The Pro Bike Tool CO2 Inflator is a neatly machined, fully controllable way to blast your tyres – hopefully without giving yourself frostbite. The protective sleeve sits securely, if just a little skimpily, on 16g cartridges. Just mind that the equally snug valve union doesn't remove your valve core afterwards...

• Pros: Totally airtight, tidy machining, includes spare o-ring (and its measurement)
• Cons: Can unscrew valve cores, foam sleeve only just fits three fingers, no canisters included

This aluminium inflator is an attractively carved little device that works well. The knurled sections give excellent grip, the foam sleeve fits tightly enough that you can screw the cartridge in with it on, and the easily replaceable o-rings leak nothing.

> Buy this online here

O-rings can be irritatingly tricky to measure accurately, so having the size listed on the included spare (4.5mm x 3mm) is appreciated. Note that's 4.5mm internal diameter, not external.

It fits both Presta and Schrader valves without modification, and an all-up system weight of 85g is negligible when stowed.

The valve gives easy and progressive control over gas flow, which can help when seating awkward beads or if you find yourself sans hand protection. The good, clear instructions say not to open further than 45 degrees – only around 15mm movement at the lever end – and even this gives a blast forceful enough to turn everything a crystalline white. Including your fingers. Keeping the flow lower and slower creates less skin-gluing frost.

The head fits any weight of threaded cartridge (from 12g to 25g), though the sleeve only fits 16g versions. That's enough to get one tyre up to a rideable pressure.

The exact pressure depends on two things: tyre volume and technique. The handy inflation chart on Pro's site implies around 100psi with a 25mm tyre (our own testing bears that out), and says 88psi for a 28mm. However, I never got far over 70psi into my own 28mm tyres using a 16g cartridge.

> How to choose your correct tyre pressure

Partly, that's my fault. For instance, having realised after a few uses that there's no hiss at all to let you know the cartridge has pierced (sealing is excellent), and mindful of crushing the seal, I screwed it in less tightly – only to lose pressure once I fired the device.

Another time I screwed the head onto the valve too tightly and ended up unscrewing the core along with it afterwards... It took (careful) use of pliers to get it back out. Obviously, the air in the tyre came out much more easily. That mistake can be a ride-ender.

It seems you can also kind of 'freeze weld' the head to the valve. Waiting a few seconds for things to warm back up stopped my problems with cores, and seems a good idea.

Cartridges won't completely empty into one tyre – the pressures even out after 5-8 seconds – but what remains in a 16g is barely enough to get the rim off the floor of another flat tyre. Pack larger cylinders if you want multiple charges from that handy valve.

Maybe I'm too enthusiastic with the gas flow (inflators are about speed, right?), but if I held this device as Pro shows in its promo pictures I'd have fewer fingers than Ranulph Fiennes by now. Even being careful I burnt a careless finger on the bottom of the cartridge, and there's only just room to cram three digits onto the foam. Full gloves are a help.

> Buyer's Guide: 15 of the best pumps and CO₂ inflators

Pricing is reasonable for a controllable inflator – Genuine Innovations' AirChuck+ is £29.99, though that comes with a 20g canister – but there are a few, such as LifeLine's Control Valve one at £12.99, for less. Genuine Innovations' Ultraflate CO2 Inflator is the same price as the Pro Bike Tool, but includes a 20g canister.

The more common 'dump and run' options, such as Specialized's SWAT Mini or Fabric's Trigger, meanwhile, hover around the £10 mark (at least online).

The Pro Bike Tool CO2 Inflator is well made, attractive in the way machined bits of anodised aluminium so often are, and both easy and effective to use. It's a good choice, in other words.

Verdict

A really well made valve-controlled inflator that promises to last