ROCKBROS Mini Bike Pump AS1 Portable Electric Bicycle Pump100PSI Tiny Bike Air Pump Tire Inflator Type-C Rechargeable Battery with Presta Schrader Valve, Cycling Gifts for Men Women

Just got this a few hours ago, charged it up, and completely deflated my 2.2" x 700c Continental Race Kings and kept reinflating to 24.5 psi until the battery was dead. I got two full inflations, and on the third inflation, the battery was dead once the tire hit 20.5 psi. That, in my opinion, is excellent value for the money. It weighs less than two CO2 cartridges and a mini-pump, and the form factor takes up less space than the aforementioned items. Some more details about the test parameters. Ambient temperature was 72ºF. This is significant as most batteries suffer from diminished performance in the winter. I'll have to put it in the refrigerator (typically around 38º F to 40ºF, which coincidentally is just above my low tolerance level for 20 miles of gravel riding) and see how it does under those conditions. My rims also measure 25 mm internal. A rim like the Zipp Firecrest XPLR has a 32 mm internal width, which actually increases the volume of air inside the tire (this is why rims with wider internal measurements can run lower tire pressures). Of course, rims with wider internal measurements can run lower tire pressures so... it might balance out. A note about use: It appears as if the air intake is around the USB-C charging port. The port is located in a position where you naturally put a finger right over it. If you do that, it will stall out. It happened twice, but I quickly realized what was happening. I would suggest a way to improve this product would be to move the intake if possible, though this may be limited by the design of the internal pump. Putting the intake on the back of the unit would probably be ideal. I considered giving this four stars, because it doesn't have a feature I want. In reality, this is a feature I'm willing to pay more for SO, for the price they're charging and the value this product delivers, this is absolutely a five-star product, no doubt. Okay, so what do I want? I like the size. In testing this pump I found that my "thumb tire pressure gauge" was calibrated to 20 psi. On several tires, my thumb thought the tire was up to pressure when it hit 20 PSI (so in the field I just have to keep pumping for about 25 seconds longer to hit 24.5, my target pressure for my rear wheel). I would pay more for a device that kept this form factor, but automatically cut off at the desired pressure. The interface to set that pressure would be via BlueTooth and an app. I'm not sure if this is technically feasible. Perhaps there's an indirect way to measure pressure through motor performance as the pressure increases (anecdotally, it sounds like the RPMs may decrease a little as the pressure increases, which might be an indirect proxy for pressure if it was found to be repeatable). So, what does this product mean for me? It means that on gravel rides in more populated areas, I will be leaving the CO2 and the mini pump behind. If I'm solo in a less populated area, I will still leave the CO2 behind, but I will bring a mini hand pump, just in case. Electronics fail, and Murphy is a jerk. Mini-pumps are a pain, but they're a simpler system that is less likely to fail. This is an AWESOME product. I was totally skeptical and thought I'd be sending it back. Well done, RockBros!

Ironically, after purchasing the product I had flats on successive weekends, each time during cold winter rides. There's nothing worse than a long flat fix when you're freezing on the road side. Each time it took about 2 minutes of time for the pump, which operated flawlessly. Here's a few aspects that the professional reviews forget to mention: 1: Unlike a C02 cartridge, you can partially inflate a tube. I like to add a little air to the tube to give it shape before the install. That's something you can't do with a C02 cartridge. 2: You are not limited by having once chance. I once had a nightmare of a winter flat and the C02 cartridge wouldn't work. In that case, it was one and done. 3: It's very small. I have I tiny seat bag that is barely visible. I carry this pump and two TPU tubes, and it's barely visible. One bit of advice: it's counter intuitive, but you start the pump before mounting it on to the tire. Essentially you push start, it starts pumping, and you slip it over the presta valve. There's no way to gauge the pressure level. I do this purely by feel, because the goal is to complete the ride and get home. I typically roll at 90 psi, and am not concerned that my feel test results in a 75 or 95 psi pressure level.

Maybe I got a dud from Rockbros an otherwise great product company Fantastic form factor and size. Easy to charge and fills bike tires in a jiffy. I tried had home a couple of time. However. on 2 occasions when we needed it there was near zero juice in a previously fully charged unit. The unit was fully charged less than a week ago was in my bike bag. Luckily one of us had the conventional pump - however slow it was more reliable. Very mixed as my trust for the rechargeable pumps is currently shattered. I work in the renewables/ storage area and know batteries last longer and products can be designed better. Another not so important issue is that it does not display pressure. But that's ok as long as you fill enough to complete your ride. There are many 4 and 5 star reviews so I am guessing i was one of the few who got a lemon.

Unfortunately, my pump stopped working after a few uses. HOWEVER, I reached out to ROCKBROS Customer Service, and they were quick to replace my mini pump without hesitation. Excellent Service!!!

I haven't used it to inflate a tire yet but it is a nice compact size. I did turn it on to test and the air flow seems to be sufficient. It fits easily in a small saddle bag with a TPU tube, multi tool and tire lever. In the package is a USB C charge cord, rubber addapter for schrader, presta is installed, and a silicone cover. Be aware there is no pressure gauge or battery level indicator just an LED indicator. I still consider this a win for a back up emergency pump to carry on the bike.

The product is great but it doesn't hold a charge enough from bike ride to bike ride. You have to charge before each ride.

Wow! I like it alot. I have used this at home to test it several times and wow! Easy to use, very portable and it pumps air in my 700cx24mm tire pretty darn fast. I carry a large battery pack that supplies power to my two Gopro 10 cameras so if I need to recharge this (that recharges itself in 5 minutes) I can do it fairly easy. If u dont have a extra power pack to recharge this make sure u change ur tube & tire right the 1st time. Always check for foreign objects stuck in the tire before u put it back on. ALWAYS! Update, although id rather not talk about it but I did get a flat! Darn it! I'd use stronger words but, anyway this was a freakin life saver. I fixed the flat and connected this and started it up. I left it alone and continued to clean up all my crap from fixing the flat and when I was almost the pump was done. I plugged it in again (I carry a large charger for my gopros) and recharged it as I continued to clean up. That's how fast this little bugger is. I'm soooo glad I bought this. Im ready to get another as a back up because some manufacturers only make so many then move on to something else and I'll never see this again. I'm pretty sure I'm buying another very soon. O!, good luck fixing ur future flat tires and remember, stay cool. I fix flats better & faster if ur not pissed off.

Perfect to travel with and keep in my bike bag for quick tire changes