georgebonn

The Evo 26GX has a rather strong spring on the throttle lever. Does this not put a rather strong load on the throttle servo ?

What function does the spring perform on the Evo ?

Thanks.......George Bonn

DarZeelon

George,


Some recommend that this spring be removed; but in reality, the throttle can still be operated by a 1.5 kg micro servo.

Meesh

My Feedback: (135)

Leave it on! If you remove it, over time the engine vibration will cause the holes for the throttle plate shaft in the carburator to become worn.

pe reivers

The spring has two fuctions:
1) it will return the throttle valve plate and eliminate backlash in the throttle operating system.
2) it puts a sideways load on the throttle valve.

ad 1)
reducing the spring load to servo acceptable limits is a good thing. Servo arm geometry can help here to overcome heavy spring loads, but it also is possible to hook the spring into the next available hole and thus reduce spring tension. If play in the system is not an issue (very rare case!), just unhook the spring.

ad 2)
The spring places an axial load on the butterfly valve, and prevents it's hammering on the sides of the carb bore right next to the valve shaft. Eventually this hammering will cause valve shaft binding, which will prevent proper throttle operation. If the spring is removed, other means of keeping the valve in place need to be employed.. Not difficult to do.