The engine is likely to be speed governed in some way. Depending on the method employed there is likely no direct connection between the throttle lever and the throttle butterfly, assuming it is a petrol engine.
Unless it is fitted with a governed carburettor, which would have a direct connection, the throttle lever is usually connected to the throttle butterfly by a fairly weak spring. When the throttle lever is moved to increase the engine speed, as the speed rises the governor which is also connected to the throttle butterfly will pull back tending to close the butterfly until the throttle spring and the governor are equal to each other and an increased stable speed is achieved.
A degree of maintenance is usually needed as the spring(s) rust and fall off, the rods and pivots become bent, worn, detached or seized...
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The engine is likely to be speed governed in some way. Depending on the method employed there is likely no direct connection between the throttle lever and the throttle butterfly, assuming it is a petrol engine.
Unless it is fitted with a governed carburettor, which would have a direct connection, the throttle lever is usually connected to the throttle butterfly by a fairly weak spring. When the throttle lever is moved to increase the engine speed, as the speed rises the governor which is also connected to the throttle butterfly will pull back tending to close the butterfly until the throttle spring and the governor are equal to each other and an increased stable speed is achieved.
A degree of maintenance is usually needed as the spring(s) rust and fall off, the rods and pivots become bent, worn, detached or seized...