May 22, 2010
One of the first things I do before setting out on my bike, whether it's for a day ride or a full blown tour, I always check my tire pressure. Over time, your tubes naturally leak air, so it's always a good idea to have them topped off to help prevent pinch flats, and improve the tire's rolling efficiency. One piece of equipment that can take that process out of your routine is the Pump-Hub.
The Pump-Hub is a unique hub that will pump air into your tire as you ride. Using two simple switches, a pressure adjustment screw, and a hose line running from the hub to the tube valve, the hub will use the force of the spinning wheel to pump air into the tire until it is full. Once the tire is full, the pump automatically shuts off, and you're topped off.
Installation of the Pump-Hub is pretty simple. The hub comes pre-built on either a Velocity Aerohead rim, or a Salsa Delgado rim. Once you have your tire and tube on the rim, you will need to connect the hose line to the presta valve. The model I demoed required the hose to be cut to a precise length, however, newer models will have a telescoping fitting at the end, which provides plenty of room for error, and the ability to run different valve stem lengths without re-cutting the hose.
Once the hose is connected to the valve stem, simply put the wheels onto your bike. There is a tab on the non-driveside axle, which needs to be lined up into the dropout. This feature allows axle torque against the wheel rotation, which assists the pump. When you have your wheels in place, you will notice two levers on the non-driveside of the hub. The longer lever activates the pump, while the shorter lever turns the pump off. Turn the pump on by pulling the longer lever towards you (away from the bike), and start spinning the wheel. You will hear a loud clicking noise, almost as though you have baseball cards stuck in your spokes. Air will begin to pump from the hub to the tube. Once you get enough pressure in the tire to start riding, you can hop on the bike, and ride until the clicking noise stops. You will hear the smaller lever on the hub pop into place and turn the pump off. For a 700x32 touring tire I was able to go from 40psi to 90psi in just under a mile.
The hub will arrive to you at a preset pressure. If at any point you would like to change the pressure, there is a small flat head screw on the non-driveside faceplate of the hub which adjusts the pressure. Turning the screw clockwise will increase the pressure, and turning it counter-clockwise will decrease the pressure setting. The pressure will rise or drop 15psi for a quarter turn.
The quality of the hub is right up there with most standard hubs, and rolls smoothly with cartridge sealed bearings. The hose is also very durable (which you will notice when cutting it to length), and stands up very well against abrasions. When attached snugly, it will be right in line with your spokes, and won't rub on the frame. When the pump is active, you will notice a slight amount of resistance, but as soon as it turns off, the resistance goes away.
Built with Velocity Aerohead rims, a front and rear wheel will run $499, which is very competitive with new wheelsets, especially considering the innovation. The product is still in its early stages, but is very well built. These aren't being stocked in shops around the country quite yet. They are being produced in Oakland, California, and residents in that area can give them a look at Hayward Bicycles.
These hubs are a great way to keep your pressure up over a long period of time, will ensure full pressure is achieved, and could also be a great tool for ultra-light tourists.
Photos by Josh Tack.
TOURING GEAR AND TIPS is written by Joshua Tack of Adventure Cycling's member services department. It appears weekly, highlighting technical aspects of bicycle touring and advice to help better prepare you for the journey ahead.