Electric battery-powered air pumps in general
These little marvels of technology are fascinating in themselves: small and light, they promise to inflate car and bicycle tyres without muscle power. Sounds tempting. Because anyone who has ever had a puncture on the road and been forced to fill an empty road bike tyre (8 bar) or a 29er MTB tyre with a small air pump knows what I’m talking about. This is one of the reasons why I swear by CO2 pumps, even though inflating with them requires skill and practice.
One more reason for me to test a battery-operated pump. I chose the second version of Xiaomi’s Mijia, especially since its predecessor, released in 2019, had already won many comparative tests.
What is new? What has been changed?
The battery capacity (2,000 mAh) and the size of the case (12.4 x 7.1 x 4.5 cm) have remained unchanged. The design is also unchanged; it reminds me of my first iPod and sometimes of a padlock.
For charging, however, there is a USB-C port this time. The performance is said to have increased by 45.4%, which is achieved by the new pressure sensor. Instead of 5 car tyres as before, 8 car tyres can now be filled with the new pump … but I am less interested in that.
More interesting is the maximum tyre pressure, which is given as 10.3 bar. I am curious!
The handling …
… is quickly explained: The end of the tube is screwed onto the valve; an adapter is included for the narrow French valves or for flash valves. With the buttons on the front you then select the type of tyre (car, bike, etc.) and the desired air pressure (in bar or psi). The “correct” air pressure for each tyre is usually marked on the tyre itself; please follow the manufacturer’s instructions!
The pumping process starts after pressing the button … so much for the theory!
Let the tests begin!
There are enough test subjects for the small battery pump in our household: For the test, I limited myself to the wheels or tyre sizes that I use most often myself.
Test No. 1: MTB Continental RaceKing 29×2.2 (55-622); air pressure 2.2 bar
Test No. 2: Road bike Continental GP 5000 28 (25-622) 7.6 bar
For the large-volume MTB tyre, the small pump took a little less than 2 minutes; for the road bike tyre a little more (see video!). I think that’s quite OK, considering how long it can take to achieve the same result with a small mini air pump, which many cyclists carry with them because they want to save weight. And anyone who has ever had to inflate a tyre in sub-zero temperatures or in the rain …
A CO2 cartridge compressor is of course much faster, but in some cases the application is a bit tricky and the wear and tear on cartridges is not exactly environmentally friendly.
Assessment and evaluation
Pro: The pump is easy to use; simply screw it onto the valve, set the desired tyre pressure and start. After just under 2 minutes, the tyre is at the target pressure without any effort. Provided the battery is not empty 😉 And you can use the 2 minutes wisely … Bio-break, eat, drink … .
Cons: The hose of the Mijia is quite short, which makes handling difficult at times. An extension and/or an adapter can help. Even if it sounds strange, I recommend practising this procedure at home; it saves unnecessary trouble on the road!
Of course, you have to make sure that the battery is charged. And then there is the weight of almost 500g; other pumps are much lighter, although they have other disadvantages.
By the way, I had slight problems with the French valves. After filling and unscrewing the pump, the valve insert came loose, was unscrewed and the tyre was flat again. This can be avoided by screwing the pump hose on a little less tightly. However, something similar has happened to me with other pumps.
My personal conclusion
Strong, handy, stylish and anything but a toy! In my private environment, i.e. with my family, friends and neighbours, this electric battery pump has caused a lot of positive feedback and many would have liked to take the pump from me!
After the positive overall impression, I will definitely continue to use it at home, even if I still stick to my SKS racing compressor. But for on the road, the little power dwarf from Xiaomi is just too heavy for me; here I will remain loyal to my CO2 pump!