Profile Racing Hub Specs

Using these measurements, in addition to the ERD (Effective Rim Diameter) of the rim you intend to use, you can calculate, using one of several online spoke calculators, what length spoke you'll need.

Keep in mind, the spokes in a 20" wheel are much shorter than the spokes in a mountain bike or road wheel, so you don't need to be as precise as you do with a larger wheel. On the vast majority of the BMX wheels that we build here, we use the same length spokes front and rear, even on the Mini Cassette hub with it's differently sized flanges. When you're calculating the length of a set of BMX wheels, you can probably take the average of the three lengths your calculations give you and just buy one length of spoke. This is assuming that the three lengths are within 2-3mm of each other. If the difference is more than that, you should order the different lengths in order to get the strongest results.

The most common wheels we build here are all built with Sun Rims, and they're usually built in a 4 cross spoke pattern.