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The Topeak SmartGauge D2 is a well-designed, tough, user-friendly and compact digital pressure gauge. It fits both Presta and Schrader valves, gives live readings of changing pressures and will last months, if not years, on a single battery. There's little not to like – it's the perfect antidote to analogue track pump readings that are often inaccurate and hard to see.
Now large-volume road rubber is common and lower pressures possible – even encouraged – tyre pressure is even more central to ride quality. The Topeak SmartGauge D2 is faff-free way of getting the exact right pressure each time you ride, and it's so simple (you don't even need the instructions) there's never any reason not to hook it up.
That includes when not even going out. Being able to keep my turbo bike's pressure consistent means I don't have to recalibrate the Tacx Vortex every time I ride, which is extremely useful. But while consistency is arguably the most important thing with readings like these, I did check the SmartGauge D2 for accuracy against both a known-accurate car compressor and bike pump (the benefits of having borderline-OCD cycling friends...).
The Topeak appears to under-read by 1-2psi at 20psi (measured on a car tyre). This is easily within acceptable limits for cycling use, and might only ever be a problem if you were inflating your tyres to somebody else's pressure. And in any case, it's very hard to guarantee the other person has a truly accurate gauge either.
Its most useful accuracy is in being able to maintain a consistent pressure over time, displayed in 1cm high digits. Compare this to the analogue scale on my favourite track pump; there the needle travels through 40psi in just over a centimetre.
The 'SmartHead' rotates through 180° and has a simple yellow slider for toggling between Presta and Schrader valves. With Presta there's a knack to engaging it quickly so you don't lose too much air, though with Schrader that's not an issue.
At higher pressures on narrower tyres you can lose around 4psi per use – and that's where the bleed function comes in useful. The best thing is to overinflate the tyre and then bleed air out with the button, while the flashing display gives a live pressure reading.
The SmartGauge bleeps when it has a steady reading (psi, bar or kg/cm2) and displays it for 25 seconds before auto-shutdown kicks in to save the battery. Long enough to read easily, then, but not long enough to check back if you subsequently forget. On the subject of battery life, I haven't seen it quoted anywhere but I would estimate the single CR2032 to be good for a few thousand measurements.
This Topeak can measure up to 250psi, meaning it could see use on a mountain bike fork or shocks if you're also riding dirt. We haven't reviewed many pressure gauges at road.cc, but our gnarlier cousins at off.road.cc tested the £34 Fabric Accubar last year, though it only goes up to 40psi and is clearly aimed at mountain bikers.
They also tested Topeak's Shuttle Digital, which goes up to 300psi, measures half psi and can be attached inline on a pump; the D2 doesn't do that, but then it also doesn't cost £55.99. So the Topeak SmartGauge D2 looks like good value for money – yes, there are cheaper gauges, such as Schwalbe's Airmax Pro at £17.99, but that lacks a bleed button, has a smaller display and only goes up to 160psi.
The Topeak SmartGauge D2 is a simple, ruggedly-built and extremely useful little gadget that makes getting consistent and accurate pressure a breeze (pardon the pun). It fits both common valve types, reads high enough to do off-road duty too and is a very useful thing to have in today's big-tyre road riding world.
Easy-to-use, tough, compact and reliable pressure gauge for an entirely reasonable price
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road.cc test report
Make and model: Topeak SmartGauge D2
Size tested: n/a
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
From Topeak's website:
"The second-generation digital gauge features a rotating SmartHead and works seamlessly with Presta and Schrader valves without changing parts. Precision digital gauge reads up to 250 psi / 17 bar and is designed for use with tires, suspension forks and rear shock units. LCD display can be programmed to show pressure in psi, Bar, or kg/cm2."
Tell us some more about the technical aspects of the product?
From Topeak's website:
ADDED FEATURES Rotating head, Air release button
BATTERY CR2032 x 1 (included)
BODY Engineering grade polymer
CAPACITY Reads 250 psi / 17 bar
GAUGE Digital - PSI, Bar, kg/cm2
HEAD SmartHead®, Fits Presta / Schrader valves
SIZE 10.2 x 4.5 x 3.5 cm / 4' x 1.8' x 1.4'
WEIGHT 65 g / 2.29 oz
The 'engineering grade polymer' (plastic) seems tough and the whole thing is solidly built.
Very easy to operate and understand.
Topeak's own instructions tell you not to violently shake or drop the gauge, so it does need to be treated with respect if it's to carry on functioning accurately, but it's otherwise built to last.
Light enough to carry in a jersey pocket.
It's comfortable enough in the hand, but only really needs to be held between finger a thumb on the valve.
Functionality, user-friendliness, build, accuracy and overall usefulness are all above average for a pressure gauge.
Tell us how the product performed overall when used for its designed purpose
Tell us what you particularly liked about the product
I could use it without reading the instructions – it's that simple.
Tell us what you particularly disliked about the product
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
There are cheaper gauges, such as the Schwalbe Airmax Pro at £17.99, but that lacks a bleed button, has a smaller display and only goes up to 160psi. Meanwhile the Fabric Accubar is £34, but only goes up to 40psi and is clearly aimed at mountain bikers. Topeak's own Shuttle Digital goes up to 300psi, measures in half psi and can be attached inline on a pump... but costs £55.99. So the Topeak SmartGauge D2 looks like good value for money.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
The Topeak SmartGauge D2 is so simple to operate and so easy to read. I was also impressed with its crisp display, intuitive button layout and rotating head that switches easily between Presta and Schrader. If you want it to read to the half psi and connect to a pump you have to pay nearly double, so this version gets a well deserved 'exceptional'.
About the tester
I usually ride: Racer Rosa custom alu My best bike is: Colnago Master Olympic
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, touring, club rides, sportives, School run on a tandem