Description
BSA pinewood derby wheels are well designed, but unfortunately the wheels vary considerably from mold to mold. Most of the wheels are not perfectly round and the tread surface is not even.
Our Speed Wheels are official BSA wheels which are sorted by mold number, and then precision machined to tight tolerances with a HAAS CNC (computerized) lathe using proprietary fixtures and tooling. The precision of this machining cannot be duplicated on hobby lathes.
To provide you with an awesome set of wheels, we perform the following operations:
- The wheels are sorted by mold number, and any defective wheels are discarded.
- The wheel tread is lightly lathed to achieve a perfectly round wheel, and a flat tread surface.
If you would like to order wheels with a particular mold number, Click Here.
Benefits
- Round and smooth wheels roll faster than standard wheels.
- Matched mold numbers ensures that the bore diameter and other wheel measurements are identical, maximizing performance.
Usage
The Official BSA Speed Wheels can be used without any additional preparation. However, the following steps can be performed for additional speed:
- Polish inside edge - Place a wheel mandrel in a drill, mount a wheel on a wheel mandrel, start the drill, and lightly polish the inside edge of the wheel (opposite the spokes) with a polishing compound or very fine wet sandpaper (minimum 600 grit).
- Polish the Bore - Polish the wheel bore with graphite or bore polish. Click here for more information.
Important Note
The lathing operation removes a small amount of tread surface. The serrated edge is intact. The tread reduction is barely visible to the eye, but is measurable with a caliper. If your race restricts the use of lathed wheels, consider using our specialty tools and supplies to prepare a set of raw wheels.
I personally have compared Maximum Velocity's Speed Axles and Speed Wheels versus the others on a track with an accurate timer; they are the fastest combination on the market today! What is really fantastic is that the wheels and axles are ready to go; you don't need any special tools. Just a quick polish on the wheels and axles and you are ready to go!
Francis B. - September 23
Comparison Chart and Photos of Matched Speed Wheel Types
| Model | Trued Tread | Coned Outer Hub | Trimmed Edge | Reamed Bore | Weight Reduced |
|---|---|---|---|---|---|
| 4090/4091 | Yes | No | No | No | No |
| 4080/4081 | Yes | Yes | Yes | Yes | No |
| 4070/4071 | Yes | Yes | Yes | Yes | Yes |
| 4060/4061 | Yes | Yes | Yes | Yes | Yes |
Technical Information for 4090/4091 Wheels
Wheel Diameter: 1.170 ± 0.005 (Raw Wheels: 1.182 to 1.185)
Wheel Bore ID: 0.096 minimum
Wheel Weight: 2.6 grams/wheel (Raw Wheels: 2.7 grams/wheel)
