[Ryland]

I'm running the stock motor in my Commuti-car, same motor as the Citi-car and the 3.5hp motor is rated at 6hp when forced cooled on the commuti-car, seeing a constant 200 to 250 amps is common, seeing 300 to 400 amps is common when going up hills and I've seen my motor draw a peek of over 500 amps when going up steep hills, that is why I installed a 650 amp solid state speed controller, so the speed controller wouldn't be the weakest point, instead the batteries with their max discharge rate of around 550 amps become the limiting factor and if your car has the contactor speed controls instead of a solid state speed controller you can see 600+ amps being pulled by this 125 amp motor you have for a few seconds at a time, but it's not a good idea because you can brake or melt parts of the drive train!
I'm sure it's slight over kill, but I did a few upgrades on my car including 00 welding cable between all of the batteries and the speed controller, stock battery cables are 4 gauge, that controller is bragging about having 10 gauge (large the number the smaller the cable size, 00 is nice and big) the old 4 gauge battery cables would get warm, I've melted the posts off batteries, vaporized 8 and 10 gauge wires inside the motor twice now and had my old battery cables to hot enough that I was worried about melting the insulation on them.
Your 3.5hp motor will put out more power at it's peek, around 28hp or more, so don't underestimate it, if you want better performance, save up for some good lithium batteries, but make sure they can handle the discharge or you will destroy some good lithium batteries, if you do end up with lithium batteries you might look at going with 72v and just limit your driving speed so you don't over speed your motor and blow it up.