I have a 1970’s model Club Car Caroche and replaced micro switches..new cables..new wires everything new but cable from motor to batteries. It is jerky on the the start. Once gets up to speed fine but trying to go slow from stop it’s very jerky...please help!
That was the chief complaint about that model of cart. The way that the motor speed is controlled (as I’m sure you already know) is by switching those coils of wire (resistors) in and out of being in series with the motor. As they are switched, it is a “digital” thing. As you step down on the pedal, You start out with all of the resistors in the series circuit and then as you depress the pedal you start activating switches which remove the resistors one at a time in a rather abrupt process. There are, however, some things that can exaggerate the “jumpiness”:
Batteries: If the batteries are weak or not properly charged, the cart won’t really start to take off until you get into the second or third “speed” and then “wham”, off you go as soon as there is enough energy to overcome the stalled position of the motor.
Resistors: I’ve had cases where the original resistors had been replaced with ones that didn’t have the same resistance as the originals. They were designed in such a fashion as to make things as smooth as possible, though it is not perfect at best. See if they look like they are original or have been messed with.
Switch activator: The little slide that turns the switches on sequentially can get worn and not “pick up” the switch as soon as it should.
Tire pressure: If the tires offer too much rolling resistance, that complicates the “take off”.
The later model Club Cars had more resistor to sort of smooth things out a bit (more but smaller increments). Maybe someone else will have some other suggestions.
P.S. I was assuming that you have already confirmed that the solenoids are OK. As each switch “makes” you should hear an associated “clunk” as the solenoid that it is associated with energizes. If one of them doesn’t energize (because it’s bad), or if one has “welded” contacts then that changes everything. Let’s say that the highest speed solenoid had “welded contacts”. As soon as the first solenoid energizes, the “welded” solenoid acts as if had been energized, and away you go at the highest speed. I should have mentioned that, but it sounds like you are already aware of how the switches and solenoids operate.