Cycle Wheel Terminology
When you look at the different manufacturers wheels, you'll find a lot of different terms used to describe the designs. Some of these are purely manufacturers terms for their own development and others are universal across all cycle wheels. We've covered most of them below.
To cyclists who don't compete, the profile of a wheel might not mean very much, but anyone who has watched cycle races in the Tour de France or the Olympics will have noticed high profile wheels in use. They are the ones that appear to be partly or completely solid, instead of having spokes.
Most standard bikes have 'low profile' wheels where the rim has a depth of around 10cm, which forms the braking surface. Higher profile wheels use lightweight metal alloy or carbon sheet at the rim end of the spokes, so there is less spoke length and a deeper rim.
In general the higher the profile, the more rigid and aerodynamic the wheel.
The higher profiles range from 38mm like the Campagnolo Pista track wheel, through 80mm like the Zipp 808, to full disc wheels for track use like the Campagnolo Ghibli, where all the spokes have been replaced.
This is a reference to spokes that are designed with a non-circular profile along their length, which helps to stop unwanted air turbulence. The aim by the wheel manufacturers is to reduce wind drag at speed and you'll find this in models like the Fulcrum Racing Zero
On the mid and top priced performance wheels the spokes are often welded to the rim, whereas the standard rims have a hole where each spoke nipple joins. Undrilled rims give extra strength and rigidity.
Tubular and Clincher wheels
Clincher is just another name for a wheel that takes an inner tube inside the tyre. A Tubular wheel is one where the tyre itself seals to the rim and keeps the air in. Obviously the design of the tubular wheel is critical to avoid air leakage and pressure drop. You'll also find tubular wheels that will also take a tyre with inner tube.
Carbon cycle wheels
You'll find carbon used in different areas on bike wheels from just a carbon rim or carbon hub, through to a complete carbon wheel. Carbon components give strength and lightness, while also being quite flexible relative to metal wheels.
Some top level wheels have ceramic based bearings and hubs which aim to give decreased friction and increased longevity with lower maintainence worries.
Variation of spoke numbers on left / right or drive side
Some wheels have more spokes positioned on the drive side of the rear wheel to give extra rigidity and responsivenesss when you are accelerating. So you'll see different spoke numbers on each side of the wheel.
You'll also see generally less spokes on the front than the rear wheels, simply because the front doesn't carry so much transmitted force.
This does the same as a freewheel arrangement (ie. allowing you to freewheel when you're not putting in any power), except that the freehub has separate gear sprockets that slide onto a carrier on the hub. This means the sprockets can be easily removed and replaced if you want different gear ratios.
(On a simple one-piece freewheel, the sprockets can be difficult to remove as they get progressively tightened by the torque from riding).