The Scorpion HK-2221 motors are built with 4mm hardened steel shafts that will last through countless hours of flying fun, but occasionally, on a "Less than Perfect" landing, you may bend or break one. For these occasions, we offer factory repalcement shafts for all the HK-22mm Scorpion Motors. Our Motor Shaft Kits include an original equipment factory shaft with the setscrew keyways already cut, a new spacer washer, and a set of 3 retaining clips. This way, when one goes flying and bounces off the wall while you are trying to install it, never to be found again, you still have a couple more to try again!
The shaft for the HK-2221 series motors measures 4mm in diameter, and is 58.7mm in long. This special version of the HK-2221 shaft has the output end of the shaft is ground down to a 2.3mm diameter to fit special applications where you need a smaller MOD 0.5 Pinion, such as an 8-tooth or 9-tooth, or where you need to use a pinion that is only available with a 2.3mm bore. The shaft kit will also fit other brushless motors that require a 4mm shaft of this length. The shafts can be cut shorter with a Dremel tool and a cut-off wheel if necessary to fit other motors.
Note: The shafts in the Scorpion motors are a slight press fit into the aluminum front housing. The shafts will not just slide out when the setscrews are removed. They need to be pressed out in a bearing press, or in a drill press, with the front houshing of the motor supported in a block of wood to prevent warping the front housing.