Crankbrothers Gem Hand Pump

Great little lightweight pump to carry with you on your bike. You won't want to use this as you main bike pump as it's very small and not really made for that. This pump is meant to be ultra portable for trail/road-side use.Having said that, it works quite well and quality feels good. It has a low-pressure/high flow mode to quickly get you up to 20ish PSI. After that, you can switch it to high-pressure/low flow mode which takes a lot more pumps, but each are easier. I was able to quickly get both my 2.6" x 29" MTB tires up from 10 PSI to 20-22 PSI (there's no guage on my version of this pump), with a little work.It comes with a frame mount that will fit under your bottle cage (you may need longer bolts, depending on how long your existing ones are). The pump snaps into it and has a rubber strap that holds it very securely. The strap can be a little tough to fasten/unfasten, but it will definitely keep the pump held in place.

Crank Brothers knocks it out of the park again! I'm quickly becoming a fan of everything Crank Brothers. This isn't just your typical frame pump, it's both a high volume pump, and a high pressure pump in one. Twist the dial at the bottom one way, and you get high volume for fast inflation. Then when it starts getting too difficult to pump, twist the dial the other way and you can keep going to get up to your needed pressure. I haven't needed to use it in the field yet but did test it in the shop a bit and have no complaints. I don't know if I'd want to use this for a 120 psi road tire but it'll be great for my 60 psi mountain bike. It comes with the typical frame mount bracket to attach alongside your water bottle. It's also small enough to fit in a medium to large size seat wedge pack. The reversible presta/schrader head is typical and just works.

This pump works way better than you'd expect such a tiny thing to work. Very little effort to pump a tire up to 40 PSI. While there is no gauge, there is a distinct change in the pump sound when you hit ~40PSI, so you have some indication of when you'd need to swap to the high pressure mode. As I keep my tires around 40, I don't really need the high pressure mode, but it surely works.Read the instructions. I found it a little confusing to switch from the default Schrader mode to the Presta mode, and ended up lodging a piece in backwards. Watched a video right after and fixed it. Don't be me :)My main complaint is with the mounting bracket -- it's sturdy, but I simply wish the mount had the pump flush with the tube, rather than sticking out to one side. I have enough clearance on my Grizl to have the pump hanging off to the side, thankfully, but your bike may not be as friendly to that. I won't take off points for it, since it worked out for me, but do keep this in mind.

High quality, compact, tough materials. Of course it takes some work to inflate a tire with such a small pump, but that is to be expected. Dual pressure setting is nice.Only slight complaint is that it is a little difficult to fit onto valve stem, and remove.Instead of rubber that squeezes down on it, I would expect a threaded brass fitting on such a nice pump.

Perfect & fit, form, & function is all there! Some have commented on it being thicker than some but I love it’s overall short and stoutness (it’s really not thick either maybe 1” round) & to the people who say it doesn’t work on Presta valves, should figure out how it works before commenting (effects sales) but YES IT DOES you unscrew the lid cap & turn the rubber piece inside around & re thread cap back on & whallllla , universal lol! But yeah love it on my aggressor pro paired with my blue crankbros stamp 1’s!! MY ONE complaint is that the head swivels freely (but not much & don’t notice when riding) so my hack with be a 1/4” round black magnet to the body for the latch to stick too to keep it in place (has a metal bar around valve switch) but really hasn’t/doesn’t bother me much! Solid Pump!

The media could not be loaded. I carry this as part of my road service kit while touring on a motorcycle. It is small enough to fit under my seat so I always have it with me. I never thought I’d have to use it until I did. One day I got a screw stuck in my tire and had to patch it on the side of the road. It took about a half hour of pumping but this little guy got me up to 25 psi. So yes, this will work on a motorcycle but it will take a while.

I actually used this to make a nebulizer setup for the backcountry. No modifications needed to the pump, cut less than 1cm off of one side of the oxygen tubing and it fits right in. Light weight, fits in our rescue bag and adds negligible weight to the aircraft. I use the high volume mode to nebulize medications.

At first the pump appears impressive. First mountain bike ride the cap unscrewed, fell off, lost. The pump is now inoperable.Took it apart for general curiosity, after one ride the internals were filled with fine silt and water, in and around the seals that create pressure.I would pass on this product.