Kyosho IH107R Rear Shock Shaft Set Mini Inferno ST

This is the rear shock shaft set for the Kyosho Mini Inferno ST.

The shaft is the polished rod that runs through the shock seals and carries the piston. It is a precision part: the O-rings ride directly on its surface, so any nick, scratch or bend destroys the seal immediately. A damaged shaft is the most common reason a shock keeps leaking no matter how many times it is rebuilt, and on a small-scale car the shafts are proportionally thinner and easier to bend than on a 1/8 chassis.

Shafts bend in the crashes that load the suspension sideways rather than vertically, and even a slight bend makes the shaft bind in its seals. That shows up as a shock that will not extend smoothly under its own spring pressure, which means the suspension is no longer following the ground properly.

These are the rear shafts specifically. The front position uses a different part number and they are not interchangeable, so confirm which end you are rebuilding. Fitment covers the Mini Inferno ST and Mini Inferno ST 09.