Most professional cyclists use one bike to train and one bike to race, but the cost of an entirely new bicycle for each is a challenge to many. Luckily, having an extra set of wheels for training to swap off and on between races is almost as good as a training bike. Your training wheels should be road-specific, but you can ease the pain of rough pavement with slightly wider tires and some extra spokes. Cheaper materials like aluminum will make your training wheels more affordable and reduce the cost of a potential accident. A set of training wheels lets you preserve your expensive carbon fiber wheels for race day.
Taking the wheels off and on your bike is an important skill to have in any self-supported race, since, at some point, you'll need to change a flat tire. Most modern wheels come with quick releases which allow the wheel to be taken out of the drops without tools, but older bikes often require a set of wrenches to loosen the two bolts that secure the wheels in the drop-outs. When you swap on your training wheels, remember to reattach your caliper brakes and properly set the rear derailleur before you ride.
An Alloy You Can Trust
The best material for your training wheels, in almost any case, is aluminum. Aluminum rims provide a better braking surface during wet conditions than steel, and a more consistent braking surface than carbon fiber in all conditions. Aluminum is lightweight and relatively inexpensive, making it easier to replace in case of an accident. You'll be paying out a few hundred dollars for aluminum wheels, where carbon wheel sets can cost more than $1,000. It's also non-corrosive, which gives it a long lifespan with little maintenance. For training wheels, aluminum is ideal because a replacement wheel is much cheaper in the event of a crash. Carbon fiber is stiffer and lighter, but can be prohibitively expensive for many riders.
Speaking of Spokes
The spoke count for a wheel determines the resilience of the rim against deformation over time. All wheels need to be trued eventually as the tension provided by the spokes begins to vary, but a higher spoke count will be able to complete more miles before needing a re-truing. If your training includes hundreds of miles per week, a higher spoke count of 32 spokes per wheel will provide a reliable, tough wheel for your workout. Your race wheels can eliminate some spokes since they'll be seeing less miles; a reduced amount of spokes will save weight, which can be critical for winning a race. A good compromise in spoke count between durability and reduced weight for your race wheels would be around 20 to 24 spokes, depending on your weight.
Tiring Yourself Out
The last component of your training wheels is the tire. For race day, the thinnest and lightest tire you can run is usually best, since a reduced contact patch will roll faster. For training, however, fixing flats can slow your routine and keep you from getting the most out of your ride. Choose a slightly wider tire than you use for race day. Twenty-three millimeters is a good width for most riders to train on. A tougher tire with Kevlar reinforcement or a flat-resistant strip will be much heavier than a race tire, but the ability to roll over bits of glass and branches without risking a puncture will keep you training longer and more consistently. Tougher tires will also go much further before needing a replacement, ultimately saving you money.