Slow ezgo

[Tim k]

Got it thank you , In a perfect world I want both torque and speed ! It has plenty of torque now it pulls the wheels off the ground.
Do I have to reprogram controller if I add 12 more volts to battery pack?

[kellybell]

It pulls the font wheels off the ground?

[Tim k]

On initial smashing of the throttle it gets air under the tires . I used to feel the spring wind up . In the car world we call it axle wrap so I stiffened up the rear spring and sistered some angle to the frame and viola she lifts. I think it has a lot to do with the height of the lift kit

[JohnnieB]

Tim, I went back and re-read your posts and see that some of your questions haven't been answered, and others not fully answered.

You are correct about the lift kit raising the center of gravity and making it easier to lift the front tires off the ground, but the fact that it does it with stock height tires means you have a lot of torque, which you should have due the the motor and controller being used.

Mathematically, going from the stock 275A controller to 500A controller should up the torque by 82% and going from a stock motor to an ES-52 Type should increase the torque by 20%, so now you should have about twice the torque the cart originally had.

However, you may not be generating that much torque if there is excessive resistance in any of the high current cables, contacts or connections.
Were all 13 high current cables upgraded to 2Ga? If not, you are losing torque and speed.
Are any high current cables, connections or components getting hot? If so, you are losing torque and speed.

I mentioned earlier that Amps=Torque and Volts=Speed, but qualified the statement by saying it was in general terms. More correctly stated; If you want to increase existing Torque, you increase Amps and if you want to increase existing Speed, you increase Volts. The key word is "existing' because existing speed depends on existing torque.

The maximum RPM a series wound motor will reach is limited by the voltage applied to it, however a mechanical load, such as turning the wheels on a golf cart, will prevent it from reaching the RPM limit determined by the applied voltage, therefore the more torque the motor generates as its RPM approaches the RPM limit dictated by the applied voltage, the faster it will spin under load.

Vic at D&D says their ES-52 Type motor should propel your cart at 16MPH and it is only going 13MPH, so your cart's amp delivery system might be lacking or the mechanical loading may be excessive.

[sportcoupe]

Since you're lifted why not run 22 or 23 inch tires? A lift and stock tires looks very funny IMO. The larger tires will net you more mph too.

[JohnnieB]

Originally Posted by sportcoupe

Since you're lifted why not run 22 or 23 inch tires? A lift and stock tires looks very funny IMO. The larger tires will net you more mph too.

Mathematically, going to a 22" tire height will up the speed to 15.9MPH and 23" tires will up it to 16.6MPH.
Of course, you will also see an 18% torque loss with 22" tires and 22% loss with 23" tires, but you will still end up with 82% or 78% more torque than stock.

However, if you get the bugs out of the system so it will do 16MPH on stock height (18") tires as Vic predicts, it should do 19.5MPH on 22" tires and 20.4MPH on 23" tires.

Personally, I'd eliminate any inefficiencies in the drive system first. But I'm an efficiency nut.

[kernal]

Originally Posted by JohnnieB

I managed not to comment on the cables, but it was a challenge.

The slider is at bottom of the control panel window, but they usually come set to 100%

The solenoid most likely isn't keeping the cart's speed down, but it is only rated at 100A or 125A, which is only 15A to 40A more than stock, so it probably won't last long feeding a 500A controller and high torque motor through 2Ga cables.

This is the solenoid I use (shown near bottom of page) http://www.cartsunlimited.net/Custom_Options.html
The nice thing is that it works with 36V, 42V and 48V battery packs.

As for finding space for batteries, I used the space in front of the driver's side wheel well for the seventh one.
Eight 6V batteries will fit under the seat, but it takes a bit of doing in a series cart. However, several people floating around here have done it.

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You might want to check for mechanical drag. (Brakes shoes dragging, wheel bearings, under-inflated tires.)

Marathons are different in this regard.

[JohnnieB]

Originally Posted by kernal

Marathons are different in this regard.

Ooooops! I missed that tidbit of info. Thanks for point it out.

Other than putting batteries in the bagwell, going to 8V batteries is about the only practical way to up the pack voltage in a Marathon.

[Tim k]

Great info. All cables are 2. Ga . None of them getting hot . I'm not that upset about the mph . I prefer the torque due to our use of the cart ( mx water tank hauler) going up hill loaded is key for us . I'm thinking if keeping tire size at 18 inch for the lower gearing pulling power . I also am stickler for efficiency that's why I have to make sure I'm on target. I'm going to replace rear diff fluid this weekend with some ATF royal purple synthetic I know its a 30w recommendation, but I think it will reduce even more drag while giving protection . The rear diff has a removable cover with a plug .... Wheres the fill plug?

[JohnnieB]

Originally Posted by Tim k

Great info. All cables are 2. Ga . None of them getting hot . I'm not that upset about the mph . I prefer the torque due to our use of the cart ( mx water tank hauler) going up hill loaded is key for us . I'm thinking if keeping tire size at 18 inch for the lower gearing pulling power . I also am stickler for efficiency that's why I have to make sure I'm on target. I'm going to replace rear diff fluid this weekend with some ATF royal purple synthetic I know its a 30w recommendation, but I think it will reduce even more drag while giving protection . The rear diff has a removable cover with a plug .... Wheres the fill plug?

That is the fill plug
ATF is not formulated for differential gears, and neither is motor oil.

I prefer Lucas, but if I was going to use a Royal Purple product and wanted to use a lower viscosity lubricant in a golf cart differential, I'd use their Max Gear 75X-90 or 75X-140. (Note: Viscosity of SAE 30 Motor oil roughly equates to SAE 85 Gear oil - See attached)

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Drop the pan to empty it and clean the metal filings out. Some people add 10 Oz of their favorite lubricating blend and carefully reinstall the pan, but I'm clumsy, so I install it dry and fill it with a pump similar to the one shown here:

http://www.amazon.com/Lumax-LX-1338-Black-Gallon-Fluid/dp/B0059HJFU0/ref=pd_sbs_auto_5

http://www.amazon.com/Lumax-LX-1338-Black-Gallon-Fluid/dp/B0059HJFU0/ref=pd_sbs_auto_5