We set up our engines (Rotax and otherwise) so that they will not idle. The reason is, when I’m not on the throttle and under braking, I do NOT want the engine pushing me forward, not even a little bit. It’s a very minor difference, but it does help just a tiny bit under braking. I don’t mind holding the throttle open slightly when idling in the pits.
Also, if you allow the engine to idle when you’re coming off the track, that tends to load the engine up with fuel, which makes it difficult to get an accurate spark plug reading to determine jetting. Better is to “hot chop” the engine. Basically, this entails running the engine at full racing speed (high RPM) then completely releasing the throttle and coasting into the pits.
Gearing… that’s kinda a judgment call. Both the straight and the slowest corner are important considerations. Generally the slow corner will be most important in a TaG, particularly if you running against a variety of engines (TaG as opposed to Rotax only). It’s often very worthwhile to work specifically on driving around the slow corner faster, which allows you to run a lower gear which gives you a little more top end.
A couple general rules:
-If you’re not revving out on the straight but are ok in the slow corner, you may want to add more gear
-If you’re in the powerband out of the slow corner but are topping out halfway down the straight, that’s probably fine.
-If you’re not in the powerband out of the slow corner, you should do everything possible to get there – unless you like getting passed 😉