Low top speed? CC Alltrax XCT500 FSIP speed motor

bmarv

Just got my Alltrax XCT500 and FSIP speed motor in from TahoeDawgZ71. Everything installed perfectly and just did some shakedown runs and the best I can get is 25mph. David pre loaded the correct field map for me. Advertised is 27.5mph on stock 18" tires from FSIP and Scotty B obtained the same results. I am on 23" tires. I have the amperage at 500a and the regen completely turned down. The max I am seeing on motor rpms is 4300-4400. The limit is set at 6000. I have a 400a solenoid and 2ga wires. Batteries are 1.5 years old and were fully charged before testing(52.1v). Batteries are Crown CR-150's.

What am I missing or where is my weak link? I was really expecting low 30's.

Top speed was 17mph before the controller and motor and my brakes are not dragging.

BGW

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Sergio

Turbo enabled as well?

Does the Alltrax monitor/log show 100% throttle?

NoleFan4Ever

Check the motor magnet poles. See if you are on 4 or 8. I believe that motor is an 8 pole..... Make sure you have Turbo

EDIT: Skip that, I just saw you are seeing 4400 rpm's so that is not the limiter.

bmarv

Turbo is enabled and my throttle is showing 100%. It gets up and rolls very quickly to 25mph, just won't go any faster even holding full throttle for a long distance.

Sergio

What does the Alltrax monitor show for Battery Voltage when You are at full speed?

scottyb

Often this type of complaint comes down to power supply. The 23s reduce torque by 27% and the motor is built for speed not torque. Plus you couldn't have a smaller 8v battery than CR-150.
Can you collect a monitor file and post it here for us to dissect. I suspect one of 2 things. The motor is drawing over 100 amps at WOT. (too much load/drag) or the battery voltage is sagging resulting in reduced motor rpms. Just a 5-7% slump in voltage would net the reduced speed reported.
Customers are getting 27.5 at 6000 rpms on 18s.
Monitor file please

bmarv

I think it was around 44v but I'm not sure. I know it did dip to 39v right at takeoff.

I did see amps peak at 460a at takeoff.

I was pressed for time this afternoon but I'll make some test runs in the morning.

bmarv

I'll grab a datalog in the morning.

I was thinking my batteries may be part or all of the issue. They were just replaced when I got the cart so I didn't get a choice. I also didn't know what I do now about carts.

scottyb

There is definitely a learning curve.
The monitor file should be the first step of analysis with these controllers.

TahoeDawgZ71

I'm thinking you may have a (lack of) power problem. The CR-150 batteries are probably the issue. I put this exact setup on a Precedent (With CR-190 Batteries) the other day with 19.5" tires and it was 4-5MPH faster than that. Since this was a regen 2 car, did you eliminate the second solenoid with the resistor coil on it? Also, make sure your tires are properly inflated and that your front end alignment is set to 1/8" toe-in. Any added resistance anywhere in the cart can scrub off speed. Jack the back of it up and spin each tire by hand to make sure the brakes aren't dragging. The cart should push easily with minimal effort. The easier it is to roll, the faster it's gonna run.