Need more torque

[jfw432]

Ok so I live on a 20% grade and my cart really crawls up my hill and honestly isn't much different than a stock cart on the flats. I have 6 - 6v Powertron batteries, 4ga cables all around, heavy duty solenoid and F&R switch, Alltrax 48500 controller, and a plum quick bandit motor. All parts are less than a year old and my brakes aren't dragging. Alignment of the wheels is good as well so I'm not really scrubbing the tires.

At first I thought the sluggish behavior was due to 22" low pressure mud tires so I changed over to 20" normal all terrain style tires and there is virtually no difference. No noticeable increase or decrease in speed, no increase in torque....nothing.

What could possibly be holding my cart back at this point? Everything in it is almost brand new.

[marianol]

Just my 2 cents.. I have a 98 TXT, stock motor, controller and solenoid. I have Sam's club Energizer a batteries (bottom of the a line :) and a 5in lift with 20 mud tires.
After stripping a hub I changed along with the 2 new HD hubs, new brake pads and while I was there got new bearings and seals from the rear axle.

After that my speed went from 13 to 16 mph.
It may be just mine but I'll check those bearings just in case.

Sent from my SAMSUNG-SM-G920A using Tapatalk

[Sir Nuke]

To be honest......I believe its a combination of your batteries......and the hill (20% grade) you live on. I too have a series cart, with a 485000, HD F&R, and SD solenoid....the only difference is mine has 2 ga cables and my motor.

Your batteries, what is their AH rating, as they (powertron) has different models. Are the standard battery?" the bottom of their line? Considering you live on a hill, you tax them more than a lot of others, I would have a set of batteries that have a lot more available power to draw on.

[JohnnieB]

Originally Posted by jfw432

Ok so I live on a 20% grade and my cart really crawls up my hill and honestly isn't much different than a stock cart on the flats. I have 6 - 6v Powertron batteries, 4ga cables all around, heavy duty solenoid and F&R switch, Alltrax 48500 controller, and a plum quick bandit motor. All parts are less than a year old and my brakes aren't dragging. Alignment of the wheels is good as well so I'm not really scrubbing the tires.

At first I thought the sluggish behavior was due to 22" low pressure mud tires so I changed over to 20" normal all terrain style tires and there is virtually no difference. No noticeable increase or decrease in speed, no increase in torque....nothing.

What could possibly be holding my cart back at this point? Everything in it is almost brand new.

All cart slow on inclines, especially Series drives, but a 20% grade is less than the 25% max grade recommend for stock EZGO carts, so something is probably holding you back.

Does the cart push easily by hand over hard level surface? It weighs half a ton, so it'll take a bit of oomph to get it moving, but once moving, keeping it rolling should take much effort.

If cart pushes easily, it might be a combination of taller than stock tires and a high speed motor (which tend to have lower than stock torque).

However, you didn't notice a change in torque or speed going from 22" down to 20" tires. Mathematically, that should have been a 8.2% increase in torque and a 11.1% decrease in speed, but with the low pressure mud tires, the cart wouldn't be reaching its theoretical top speed, so no change in speed might not be abnormal. On the other hand, there should have been an increase in torque.

Are any of the high current cables or connections getting hot?
What is the Max Output Current slider set to in the AXE controller?
What is the armature amp draw when climbing the 20% grade? (Post a data log file in CSV format if possible. It will have to be Zipped to attach to a post on the BGW forum.)

[jfw432]

Originally Posted by Sir Nuke

To be honest......I believe its a combination of your batteries......and the hill (20% grade) you live on. I too have a series cart, with a 485000, HD F&R, and SD solenoid....the only difference is mine has 2 ga cables and my motor.

Your batteries, what is their AH rating, as they (powertron) has different models. Are the standard battery?" the bottom of their line? Considering you live on a hill, you tax them more than a lot of others, I would have a set of batteries that have a lot more available power to draw on.

The batteries are Powertron P2000 batteries. I don't really know where that stacks up in their line but they are all within about 0.03v of each other.

Originally Posted by JohnnieB

Does the cart push easily by hand over hard level surface? It weighs half a ton, so it'll take a bit of oomph to get it moving, but once moving, keeping it rolling should take much effort.

Are any of the high current cables or connections getting hot?
What is the Max Output Current slider set to in the AXE controller?
What is the armature amp draw when climbing the 20% grade? (Post a data log file in CSV format if possible. It will have to be Zipped to attach to a post on the BGW forum.)

It is pretty easy to push on flat ground and you can keep it going pretty easily once it's going.

So apparently I learned a few things today. First being that grade and slope aren't the same. My yard is roughly a 20 degree slope. I also didn't realize you could log things from the controller. Next I learned that my cart's throttle was only going to 91% so I did the quick fix and changed the curves so that it see's 100% torque and speed at 90% throttle.

I'm pretty shocked I'm not even getting 300 amps though. That's practically stock controller territory.

[scottyb]

I'm pretty shocked I'm not even getting 300 amps though. That's practically stock controller territory.

Not exactly. The stock controller sustained output would be a bout 1/2 of that.

[DubK]

...I learned that my cart's throttle was only going to 91% so I did the quick fix and changed the curves so that it see's 100% torque and speed at 90% throttle.

How did you do this? I may need to do this to mine to get the speed and torque up as well.

[jfw432]

Originally Posted by DubK

How did you do this? I may need to do this to mine to get the speed and torque up as well.

It's in the controller settings. Download the alltrax software to a laptop and you can adjust it there. It's a pretty easy software to figure out but I believe my controller came with a setting where it was maxed out around 60% throttle and I didn't like that.

[JohnnieB]

Originally Posted by jfw432

1. The batteries are Powertron P2000 batteries. I don't really know where that stacks up in their line but they are all within about 0.03v of each other.

2. It is pretty easy to push on flat ground and you can keep it going pretty easily once it's going.

3. So apparently I learned a few things today. First being that grade and slope aren't the same.

4. My yard is roughly a 20 degree slope.

5. I also didn't realize you could log things from the controller.

6. Next I learned that my cart's throttle was only going to 91% so I did the quick fix and changed the curves so that it see's 100% torque and speed at 90% throttle.

7. I'm pretty shocked I'm not even getting 300 amps though. That's practically stock controller territory.

1. A Powertron P2000 is an economy grade battery. Basically a black box T-605 (6V-210AH).

The pack voltage drops from 38.4 when the solenoid contacts close to 31.0V at max amp draw, which is 7.4V at 283.7A, or about 2.6V per 100A.

In and of themselves, the six 6V batteries in a 36V pack drop about 1.0V per 100A and a SR controller drops about 0.18V per 100A, that leaves about 1.4V per 100A for the high current cables, connections and contacts. You have roughly 23" of 4Ga cables in your setup, which will drop about 0.58V per 100A, so you are only loosing about .83V per 100A in the connections and contacts.

Some room for improvement in the amp delivery system, but not much.

2.

3. A lot of people use % Grade and ° Slope interchangeably and they are different in meaning, which leads to confusion.

4. So your hill is 6° steeper than the max recommended incline for a stock EZGO.

5. The logged data can be very revealing when viewed and manipulated in a spreadsheet.

6. I"d check the voltage between the black and white wires from the TIS sensor. Ought to be 10V when solenoid clicks and 6V when pedal is on floor.

Also, telling the controller to clear the Throttle Auto-Cal data should have taken care of the throttle issue.

7. The controller will only pass what the motor can draw and the amp deliver system can produce.

The throttle was only pressed for ~22 seconds, which is probably within the Peak Amp Mode time frame and the controller was most likely capable of passing 575A during the entire time the pedal was pressed. Even if 22 seconds exceeds the Peak Amp window, a SR48500 controller will pass 500A for 2 minutes, 420A for 5 minutes and 380A continuously.

Even though the batteries are economy grade, your amp delivery system is more than likely capable of providing 500+ amps for more than 22 seconds without self destructing.

That leaves the motor.

[jfw432]

Originally Posted by JohnnieB

1. A Powertron P2000 is an economy grade battery. Basically a black box T-605 (6V-210AH).

The pack voltage drops from 38.4 when the solenoid contacts close to 31.0V at max amp draw, which is 7.4V at 283.7A, or about 2.6V per 100A.

In and of themselves, the six 6V batteries in a 36V pack drop about 1.0V per 100A and a SR controller drops about 0.18V per 100A, that leaves about 1.4V per 100A for the high current cables, connections and contacts. You have roughly 23" of 4Ga cables in your setup, which will drop about 0.58V per 100A, so you are only loosing about .83V per 100A in the connections and contacts.

Some room for improvement in the amp delivery system, but not much.

2.

3. A lot of people use % Grade and ° Slope interchangeably and they are different in meaning, which leads to confusion.

4. So your hill is 6° steeper than the max recommended incline for a stock EZGO.

5. The logged data can be very revealing when viewed and manipulated in a spreadsheet.

6. I"d check the voltage between the black and white wires from the TIS sensor. Ought to be 10V when solenoid clicks and 6V when pedal is on floor.

Also, telling the controller to clear the Throttle Auto-Cal data should have taken care of the throttle issue.

7. The controller will only pass what the motor can draw and the amp deliver system can produce.

The throttle was only pressed for ~22 seconds, which is probably within the Peak Amp Mode time frame and the controller was most likely capable of passing 575A during the entire time the pedal was pressed. Even if 22 seconds exceeds the Peak Amp window, a SR48500 controller will pass 500A for 2 minutes, 420A for 5 minutes and 380A continuously.

Even though the batteries are economy grade, your amp delivery system is more than likely capable of providing 500+ amps for more than 22 seconds without self destructing.

That leaves the motor.

Sorry for the slow response as I've been out of town lately. Thanks for all the good information. I wanted to follow up to make sure I'm taking away the right information. It sounds like I might be able to pull a few more amps by upgrading my cables but not very much.

Ultimately, it sounds like the motor is what is holding me back since it can't accept enough juice. Is that just all stock motors can take or is there something wrong with this one? I would've thought that by upgrading the stock motor to the Bandit motor would've fixed any issues it may have had in power delivery.