CYCLING PERFORMANCE TIPS
After you have been riding in the rain or suboptimal road conditions, you will notice a sound of metal on metal when you brake. Generally this is from grit picked up by the pads. Over time, this additional abrasion can accelerate wearing down of the rim metal itself.
To clean pads, pick out the larger pieces of foreign material with an awl, penknife or the tip of a small screwdriver. While you are at it, check the grooves on the pad. If it has been a few years, consider replacing pads if they have hardened with age.
A smooth rim will also improve braking performance. But you don't want to go overboard and remove the metal itself. A Scotch-Brite pad works well for this purpose. It's a gentle abrasive that won't remove material from the rim but will take off rubber deposits to ensure optimum braking.
To check for maintenance status remove the wheels from the bike. Turn the axles slowly with your fingers - you will feel a slight but smooth hydraulic resistance. If an axle either turns roughly or spins freely with no resistance, you need to do some maintenance. Roughness can indicate damaged bearings, too little resistance means the lubrication is gone, usually because it's been washed out by lots of rainy rides or improper bike-cleaning techniques (using high-pressure sprayers or getting solvent into the bearings).
Rear hubs are a bit more complicated to handle, front hubs are more user friendly. It does help to have the right tools. To regrease a hub, pull off the dust caps or pry them out by carefully wedging an X-Acto blade between each cap and hub. You'll see the plastic seals covering the bearings. Lift these by slipping the blade beneath, being very careful not to bend the seals.
Once you see the bearings, you can add grease if they're just dry, or take the extra step of cleaning them with solvent, drying them, and repacking them if they're gritty. The seals will pop back into place with gentle hand pressure.
Think about it, if you are considering low-spoke-count wheels, they almost never list the weight of the rims . Instead, you're told the overall wheel weight, which can be impressively light. So the first step in looking for a new wheel set, is to find out the rim weight.
The down side to lighter wheels are generally the higher cost and the decrease in durability. Aerodynamics play into this as well, but the bottom line question is where do you spend your dollars - light rims or aerodynamic rims. I found a great discussion that analyzes all wheel parameters and....... science says that rim weight is not a very big deal and aerodynamics (especially of the bike and rider) plays a much bigger role in improving performance.
Bottom Line? Losing overall wheel weight is no guarantee that you'll be faster.