Golf Cart Wizard
Cartaholic - V.I.P.
I had both a 4kw and 5kw motor so I decided to run both of them in the same golf cart to get some actual data on both. This golf cart also has the APPS throttle instead of MCOR which requires a different version of the controller. All of the new ones also have a CAN bus plug which ties the controller into the Eco Battery system installed in this cart. It is a 2022 Tempo with Eco 48v 105ah and Navitas 600A controller with CAN. Pretty much the same as the cart I built a few months ago so I will save the details except for what has changed.
Now I’m sure most people just want to know what the performance difference is between the two motors so I’ll start with that and then we’ll travel back in time to the installation. Since it’s Thanksgiving I had a wide open road in front of the shop to drive like a clown without endangering anyone else. I ran two full throttle acceleration runs with a 35mph limit as well as 2 passes cruising at a limited 25mph to see the current draw. The battery was fully charged prior to running the tests on each motor. The appropriate firmware was flashed to the controller for each motor, other settings were kept the same. The golf cart is pretty stripped down (I really don’t feel like changing motors after it’s put together) and has 19” tires.
Now I thought the 35mph limit would be a stretch but much to my surprise both motors hit that limit during each run. Frankly even that speed is scary enough so I didn’t try pushing it any higher. This really shows the benefits of having a good lithium battery especially with a controller capable of taking advantage of the power provided. I built a lead acid TAC powered cart a while ago and that (in its fully assembled state) would barely get to 30mph and struggled to build speed past 25.
The second run with both motors was pretty clean so we’ll analyze those results. Both motors did a full on burnout on the launch, you can notice that as both charts have a step at ~10 mph where the tires hooked up. Also while the speed limit was set to 35mph the torque limit starts to kick in around 32 so we will look at the 0-32 performance, I marked the point where the torque limit engaged in pink on the charts. Let’s look at the 4kw:
The 4kw motor went 0-32 in about 7 1/2 seconds, with 20-30 happening in 3 1/2. Now let’s see how much faster the 5kw is:
This run had a slight rolling start, hitting 32 in 8 1/2 seconds and going 20-30 in 4. But wait, that’s slower than the 4kw? WTF everyone knows bigger number more betterer! WRONG! This result could have easily been predicted by anyone who’s taken a look at the motor performance curves Navitas are kind enough to supply. As I mentioned in the other thread the 4kw is more of a speed motor vs. the 5kw being more so for torque, although the difference is slight. Both motors provide more performance than anyone needs in a golf cart, although I was hanging on a little harder with the 4kw.
As for the efficiency both were drawing ~30 amps at cruising speed, I think the 4kw may have been a couple amps lower but no big difference there either.
Now I’m sure most people just want to know what the performance difference is between the two motors so I’ll start with that and then we’ll travel back in time to the installation. Since it’s Thanksgiving I had a wide open road in front of the shop to drive like a clown without endangering anyone else. I ran two full throttle acceleration runs with a 35mph limit as well as 2 passes cruising at a limited 25mph to see the current draw. The battery was fully charged prior to running the tests on each motor. The appropriate firmware was flashed to the controller for each motor, other settings were kept the same. The golf cart is pretty stripped down (I really don’t feel like changing motors after it’s put together) and has 19” tires.
Now I thought the 35mph limit would be a stretch but much to my surprise both motors hit that limit during each run. Frankly even that speed is scary enough so I didn’t try pushing it any higher. This really shows the benefits of having a good lithium battery especially with a controller capable of taking advantage of the power provided. I built a lead acid TAC powered cart a while ago and that (in its fully assembled state) would barely get to 30mph and struggled to build speed past 25.
The second run with both motors was pretty clean so we’ll analyze those results. Both motors did a full on burnout on the launch, you can notice that as both charts have a step at ~10 mph where the tires hooked up. Also while the speed limit was set to 35mph the torque limit starts to kick in around 32 so we will look at the 0-32 performance, I marked the point where the torque limit engaged in pink on the charts. Let’s look at the 4kw:
The 4kw motor went 0-32 in about 7 1/2 seconds, with 20-30 happening in 3 1/2. Now let’s see how much faster the 5kw is:
This run had a slight rolling start, hitting 32 in 8 1/2 seconds and going 20-30 in 4. But wait, that’s slower than the 4kw? WTF everyone knows bigger number more betterer! WRONG! This result could have easily been predicted by anyone who’s taken a look at the motor performance curves Navitas are kind enough to supply. As I mentioned in the other thread the 4kw is more of a speed motor vs. the 5kw being more so for torque, although the difference is slight. Both motors provide more performance than anyone needs in a golf cart, although I was hanging on a little harder with the 4kw.
As for the efficiency both were drawing ~30 amps at cruising speed, I think the 4kw may have been a couple amps lower but no big difference there either.
