Lezyne is known for making high end bike accessories and shop equipment featuring CNC machining and sharp looks. Their Gauge Drive hand pump is a compact and light weight trail pump with an in-line pressure gauge to ensure tires are inflated accurately. It will drive high volume tires to a maximum pressure of 90psi using either Schrader or Presta stems.
The air line lives stashed away inside of the pump body. To use the pump it must be removed from the handle and threaded into the other end. There is a reversible attachment which adapts the pump for use with either valve system. This attachment also has a button which releases pressure from the tire with Schrader or from just the air line when using Presta valves. In both orientations, the adaptor is threaded onto the valve stem for a secure connection.
The Gauge Drive appears and feels very well made. The pump handle body slides nicely over the body with tight tolerances and a large diameter piston shaft prevents impediment due to slop. The air hose and all of its fittings go together cleanly and with out a hassle. It is also very shinny if such things resonate with you.
Looks and engineering aside, the question to pose is whether or not all the effort contributes something to my kit that isn't already covered by the pump I already have. The one I currently have was found on the side of the road but has helped me in many a pinch (pun intended). There are two ways I was hoping that the Lezyne pump would be an improvement. First, I have been meaning to be more precise with my tire pressures and having a pump with a gauge should help. Second, while the lever actuated fitting of my current pump is usually adequate there have been times where misalignment has bent a Presta valve core inadvertently. So I was interested to see if the threaded attachment system on the Lezyne can do better.
The in-line pressure gauge works the trick. I tested it against a digital gauge and the increments of the scale are the likely limitation to accuracy here. Also, when using the gauge on a Schrader valve, knocking the pressure down incrementally using the built-in release button would be an easy way to get precise pressures.
On the other hand, the threaded attachment of the Lezyne proved to be a disappointment. It's really close, but it falls short in real life action. The problem might be a classic case of over thinking a simple task. The problem is in that none of the parts of the pump can turn independently from one another. In effect this means that the entire pump assembly must be tuned together in order to attach it to the valve stem. The common household garden hose is more thought out with a freely rotating coupler, which allows it to be attached to the faucet without needing to turn the entire length of hose. A bike pump with an air hose should have the same capabilities.
One of the perks of a flexible hose is the ability to get at the valve from a good angle for a secure fit. But coordinating the entire length of the assembled pump while threading on to a temperamental Presta valve stem is a chore. Especially when you are tired or have cold, wet hands. This was the case when I set out to play around with the Gauge Drive on a rainy day with temps hovering around freezing. I was hoping to try different tire pressures searching for my sweet spot using the Gauge Drive. After ten minutes of trying to make a solid connection I gave up on my project and went about my ride hoping not to get a flat.
To be fair, it is not an impossible task. On a warmer more hospitable day I asked a few friends to try out the Gauge Drive. All agreed that while not ideal, the connection is more than doable.
Another small pitfall of the design is the need to depressurize the line before disconnecting the pump from a Presta valve stem. If the line is left pressurized while removing the pump the valve core can be extracted inadvertently. This shouldn't ever happen if you know about the potential, but there is the potential.
For this reviewer, the final thought is that some things are prone to over thinking. If a product is going to tout over the top production methods and aesthetic appeal, then it needs to be as functional as it is well made and pretty. The design philosophy that form should follow function would be a good one for Lezyne to revisit. I hope that future iterations of the Gauge Drive include one of many possible solutions to what I consider a deal breaking design flaw. The simplest that comes to mind would employ fittings like you find on pneumatic lines. They could have a universal fitting that can threaded onto either valve standard with the male end and a collar locking female coupler to connect the pump to the valve. With Lezyne's CNC and engineering capabilities it should be a snap. For now I'm sticking with my current kit.