HPI has had reports of some problems with the backplate of the S-25 engine vibrating loose, which can cause the engine to not run properly and possibly damage the engine. Upon inspecting some of the engines, it looks like the torque setting for the screws that hold on the backplate were not tight enough from the manufacturer.

To correct the problem you can either follow the instructions below, or send us the engine and we will update it for you. See the "Contact HPI" section at http://www.hpiracing.com for information on where and how to send in the engine.



Here are the instructions on how to secure the backplate screws:















Reinstall engine in reverse order of the dissassembly process, set gear mesh so that there is a small amount of play between the clutchbell and spur gear. This is a relatively easy update, the entire process should take less than 30 minutes.