I have a Euro-spec Spider Junior from 1972, which has the same dash arrangement as the roundtail. Below the dash there are levers for choke and the hand throttle. The hand throttle is correctly connected, with little bracket connected to the brake servo which holds the outer sleeve of the hand throttle cable.
The issue is that the spring which is returning the throttle pedal to upright position seems to be too strong for the hand throttle arrangement. In other words, when I pull and hold the hand throttle lever - it engages the throttle. When I let it to, the car returns to idle immediately.
Does anybody have an idea on where the problem might be?