This is an optional ST Racing Concepts Heat Treated Carbon Steel "Big Bone" Universal Driveshaft Set, and is intended for use with the HPI Blitz short course trucks. Universal driveshafts are often the first upgrade for many racers, but for years universal driveshaft design and material have remained the same, despite the drastic change in power from brushed motors and nickel cell batteries to the more powerful LiPo/Brushless combination. ST Racing Concepts has studied all the components used in traditional universal shaft's, with a focus on improving the material and design. The material is critical and equally important is the heat treatment process. After months and months of prototype testing different materials and increments of heat treating, ST Racing believes they have developed a better finished product.
First the universal driveshaft bones have increased in diameter for more
durability. They also used the same carbon steel material for the
axles, which features two sets of universal pin holes so you can get
twice the life out of the same set of axles. Even the joints and joint
pins are of carbon steel material and the pins feature a "step" for the
setscrew to more securely hold the universal driveshafts together. Even
the universal shaft roll pin at the end was not over looked. Carbon
steel at the pin although strong will unfortunately add excessive wear
to the diff outdrives, so a different material was selected just for the
shaft pin for durability and reduced wear on the diff outdrives.