Mauve the PR21BS comes with a spare Shim (0.1) in the box i no that because i have some drivers in Portugal racing with those engines and i acn say the are WHOW.
Really good engines.
So you are telling me that the spare shim not to put it we here normaly put it only to break-in the engine and then take it out.
what do you say about that.
Wat is the averge time that you get out of the engine.

Victor
JMAmodelismo-Portugal
Import of rc products