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I was reading the DerbyTalk forum and noticed a long discussion about lifting a front wheel. It got rather technical - delving in weight placement, etc. - but nevertheless I think the raised wheel is one of the most unique speed tips. Why? Because is often implemented by accident!

With axle slots it is actually quite a challenge to get all four wheels to sit on the ground. Since it only takes three points to define a plane, a pinewood derby car will readily sit on three wheels. The fourth wheel is either off the track, or only lightly sits on the track.

Why would you want to lift a front wheel? A reasonable guess is that raising a wheel reduces friction. But actually, the amount of track to wheel friction and axle to hub friction is not reduced by lifting a wheel. Instead, the friction on the other three wheels increases, compensating for the lifted wheel.

The true advantage of a lifted wheel is threefold:

1. Reduction in wheel inertia (the tendency of a rolling object to stay motionless) - When the starting gate drops, a certain amount of energy is required to start the wheels spinning. By lifting one wheel, the amount of energy required to start the wheels spinning is reduced by 25 percent (since the lifted wheel does not have to start rolling).
   
   
2. Elimination of a weak wheel/axle set - Test spin each of the wheel/axle sets, and use the poorest performing set as the raised wheel.
   
   
3. Simplified alignment - Since only one front wheel touches, only one front wheel must be aligned.
   

If you want to use this technique to full advantage, don't let it happen by accident. Instead, purpose to raise a front wheel, and make sure to use the weakest wheel/axle set in that location. To raise a front wheel when using axle slots, insert the axle at an upwards angle. If this does not give adequate clearance, then bend the axle to achieve the clearance. On the other hand, if you are using axle holes, simply drill one of the front holes 1/16 inch above the other three.

Raising a front wheel provides a relatively small benefit to overall car performance, nevertheless, it can provide enough added performance to edge out the competition. So if this technique is not disallowed, try it in your next race.

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