G3E - Upgrades not bringing the speed?

[jakehanl]

When I test the PB-6 with a meter directly it outputs at around 4850ohms at full throttle and under 100ohms at no throttle. I will hook up the controller software and see what throttle percentage is displaying there as well in a short while. What should the PB-6 be outputting? Scottyb is this the way you were suggesting that I test the throttle output with the meter directly?

[jakehanl]

Okay, so I just plugged the Curtis into the programmer and here are my values displayed at FULL throttle. In addition, the cart was charged overnight and the charge cycle complete yet still plugged in.

Heatsink Value: 13 deg C
Throttle: 100%
Duty Cycle: 0%
Cap Voltage: 49.7v
A2 Voltage: 49.8v
Battery Voltage: 49.7v
Motor Voltage: 0.0v
Motor Open: On
Plug Braking: Off

Also, When I test the PB-6 with a meter directly it outputs at around 4850ohms at full throttle and under 100ohms at no throttle.

I also contacted Lester Electrical about the fully charged voltage being a bit low; and they did just bump up the profile a notch to see how we fare with that.

Thoughts...?

[scottyb]

Your throttle range is well within the limits for 0-5k signal. I don't think this is the problem.
Whenever performance is a question I like to see the motor amperage draw vs the voltage reading.
In this case you may have to settle for some voltage readings observed at hard acceleration up a hill, etc.

[jakehanl]

I have read my voltages while under hill climbing etc. and the ranges when under full throttle going uphill are around 45v to 46v. My voltage after a full nights charge when checked several hours after the charge cycle is complete (at least 10 to 12) sits at around 50.9 volts. Mind you these are new US batteries as well (December dates). Is this normal for the batteries to sit at or around this 50.9v #?

Overall the speeds and torque are good; however I would really like to see about 5mph more for hills and flat pavement.

[scottyb]

The voltage #s for the batteries look good/normal. I think a motor upgrade is the next step. Is this a 10 spline motor shaft? If yes use the MOT-A1 for better results.

[jakehanl]

Yes it is a 10 spline motor. When switching over to the motor you suggest, does that little black bumper pice have to be pulled out of old motor and put into new motor as well? What do you think in terms of real world improvements; that the MOT-A1 will do for me? The last thing I want to do is buy another motor that I don't notice much difference with. D&D Motors (Vic) told me that an ES-81-41 motor would be the best (except he said that it may not fit without moving the shock mount). Really don't want to go down that road.

[scottyb]

The A1 is 10.4 inches long installed. Measure to make sure you have 10.5 inches at the shock. The shock mount relocation is not a big deal if you have a welder or welder buddy. Surprisingly many of our customers are doing this to install a long stack high torque motor in many of the Yamaha carts. Anyway, measure first, buy once.
The A1 on 48v with taller tires is turning in 25 mph. What size tires are on your cart?

[jakehanl]

I have 20.5" tires on 10" wheels. I am in a very hilly environment but all pavement. Do you think I'll lose lots up uphill power with the MOT-A1? Also, as far as installing the MOT-A1, do I have to take the bushing out of the old motor and put it in the new one? I'm not even sure it's called a bushing?

[scottyb]

Originally Posted by jakehanl

I have 20.5" tires on 10" wheels. I am in a very hilly environment but all pavement. Do you think I'll lose lots up uphill power with the MOT-A1? Also, as far as installing the MOT-A1, do I have to take the bushing out of the old motor and put it in the new one? I'm not even sure it's called a bushing?

It's called a bumper. You can take the old one out or source a new one. But it should be put in there to reduce the end play hammering. The A1 is a 10 hp motor - I don't see how you would loose power going from 3hp to 10. A better motor would be the Beast AMD 7114

The biggest obstacle you're facing is trying to make a street cart out of a series drive.
Have you inquired with Chuck at EMP to see what he can offer?

[jakehanl]

I just sent him an email yesterday so we'll see what he has to offer. Thanks for the tips...