TEN THINGS YOU NEED TO KNOW ABOUT WHEELS
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(1) Rims. It doesn’t matter whether the spokes are tightened properly or not, rims do bend. There is no substitute for a quality rim. The difference between a great rim and a good rim can be as little as a flat spot or as much as a broken rim. Lower-quality rims typically fail at the weld.
(2) Hubs. Stock hubs versus aftermarket—who takes the cake? At the top levels of the sport, the majority of Pro racers use either works or aftermarket hubs, many of which are billet. Billet hubs are strong and reliable but tend to be heavier than well-made cast hubs. Casting allows the designer to select the proper dimensions without having to whittle the design out of a solid chunk of metal. On a side note, the question of “turning down” (shaving material off the hub) the stock hubs to resemble the factory look often comes up. We do not recommend this.
(3) Bearings and seals. Bearings are an often-overlooked aspect of race performance. Worn, galled or seized bearings reduce wheelspin, increase drag and wobble at speed. Replacing wheel bearings at regular intervals (at least once a year) is an inexpensive service that pays dividends.
(4) Suspension. The way you set up your suspension can affect the lifespan of your wheels. Stock wheels are built to rigorous standards—with the understanding that casing jumps, flat landing or plowing into a downed bike can exceed the limits of aluminum rims, steel spokes and cast hubs. Properly set-up suspension can increase the lifespan of your wheels.
(5) Rim locks. People often ask how many rim locks to use. Rim locks stop the tire from spinning on the rim. Front wheels only need one rim lock. For rear wheels, the number can vary depending on horsepower, riding conditions and air-pressure choice. Large-displacement bikes (450cc and up) could warrant two rims locks due to the amount of wheelspin and torque. Running low air pressure would be another reason for two rim locks. If your rim only has one hole, you can drill a second hole; however, we recommend contacting a good wheel-service company such as Dubya for this procedure.
(6) Spokes and nipples. Typically, OEM spokes and nipples are of good quality; however, KTM and Husqvarna had issues this year with their front spokes. Replacing spokes can run anywhere from $50 to $200 per wheel. As with any part, spokes wear out. They stretch over time, break in collisions and suffer from lack of tightening or over-tightening. If you don’t check your spokes regularly, like before every race, you endanger the structural integrity of the wheel itself. If you over-tighten the spokes, you can stress them enough to break. The same holds true for spoke nipples. We have seen riders round off their spoke nipples by trying to tighten spokes that have stretched beyond reason. We have seen riders whose spoke nipples are so loose that they have disappeared down into the rim. We have seen spoke nipples that are so seized on the spoke that the only way to disassemble the wheel is to cut the spokes off.
(7) Too much maintenance. Think of your spokes as the strings on a guitar. The strings can be strummed to play a perfect tune when they are tensioned correctly. A loose string on a guitar delivers a false note. Many riders think that checking their spokes means tightening them. Not true. Checking them means assessing their state of tune. The biggest cause of broken spokes and ultimately broken wheels is riders who turn each spoke a little each time they ride. Doing this tunes every spoke to an F-sharp and increases the risk of having the threaded end of the spoke poke through the nipple into the inner tube.
(8) Torque wrench. This is one tool that every rider should invest in. A spoke torque wrench is the best way to make certain the spokes are serviced properly and set to the correct torque. For stock wheels, refer to the owner’s manual for these torque specs.
(9) Preserve. If you choose to run aftermarket billet hubs, there are a few things to note. These hubs are typically made from billet alloy and then anodized. The rear hub can get very hot from heat disbursed from the rear brake. When cleaning your bike after riding, it is best to only use water until everything cools down. The chemicals in cleaners will stain or streak the hubs when they are hot. Stock hubs will usually get stained regardless of what you do, especially the rear, as things like chain lube will get onto the hub when it’s hot. Also, when you wash your bike, avoid spraying directly into the area of the wheel bearings. For a deep cleaning, take the wheels off the bike and use compressed air to eliminate any moisture in the area of the bearings.
(10) Factory hubs. Factory teams can use up to 10 sets of hubs per rider per season. Depending on the number of hours they were ridden and the conditions that the hubs were used in, the used hubs may be transferred to the rider’s practice bikes the following year. Most teams use new hubs every season for safety.