Speed chip installed, whats next for more speed

[sunking]

Originally Posted by hmcnav

Batteries are 18 months reconditioned.

That is the very first thing to worry about, your batteries are SHOT and ready for the boat house to give away as anchors. Replace them with 8-volt Trojans T-875's and that will get you 48 volts and all the speed you might need.

Regardless batteries is number 1 priority before you do anything else. Otherwise you are just wasting your time and money. Kind of like Roofers showing up to build a roof before the house foundation has been built. They have nothing to work with or build upon.

[hmcnav]

So I took the cart to pick up the kids this afternoon on full charge. I got about 18-19 all the way there ( 1.25 miles) after a 15 min sit we headed back. The cart slowed to about 14 -15 mph after about 1 mile and maintained 14-15 mph the rest of the way home.

I checked the cables, the cables on the batteries we not warm, the cable from battery to controller was hot/warm. I also used a good amount of battery for just 2.5 miles, I used about 20% of battery power or 3 ticks.

[sportcoupe]

Originally Posted by sunking

your batteries are SHOT and ready for the boat house to give away as anchors.

Don't throw away the old batteries. You will need them for cores on the new set. Without cores the battery seller can charge up to $25 per missing battery for core.

[hmcnav]

I called previous owner and only battery cables were replaced when new batteries installed Cables from controller to battery back and to motor are OEM. So only 5 cables that I can see were replaced.

I also checked the tire pressure and they were at 4psi. I feel like a dumbass. I filled up 20psi max and got it up to 20mph, still now 23 like I am a supposed to get.

How would you guys check to see if brakes are dragging? Previous owner had pads replaced a few month back when he did an "Overhaul"

I am going place an order with Scotty today, I am hoping that will get me where I want to be. In the mean time I am going to search to see how to test the batteries.

Thanks all

[720Deere]

At the very least you can use a handheld voltage meter/multi-tester. If your generic bar graph is dropping several bars in less than 2.5 miles, my bet is your starting voltage is less than 38.0 and your ending voltage is probably less than 36.5. 2.5 miles in my cart over rolling terrain (paved roads) results in no more than 0.2v loss in the 2.5 year old battery pack. The bar meters are both deceiving and inaccurate.

[JohnnieB]

Originally Posted by hmcnav

1. I called previous owner and only battery cables were replaced when new batteries installed Cables from controller to battery back and to motor are OEM. So only 5 cables that I can see were replaced.

2. I also checked the tire pressure and they were at 4psi. I feel like a dumbass. I filled up 20psi max and got it up to 20mph, still now 23 like I am a supposed to get.

3. How would you guys check to see if brakes are dragging? Previous owner had pads replaced a few month back when he did an "Overhaul"

4. I am going place an order with Scotty today, I am hoping that will get me where I want to be. In the mean time I am going to search to see how to test the batteries.

Thanks all

1. When you felt the cables after a ride, the one between the battery pack and controller was "warm/hot", so it is bad. There are 10 high current cables on a 36V PDS, they should feel about the same and only be warm at most.

2. Getting closer. The bad high current cable(s) may be holding you back also. Could be battery issues also.

However, just because someone's PDS cart with 23" get 23 MPH, doesn't mean yours will, there are a lot of variables that determine cart speed.

3. As previously stated.

Originally Posted by JohnnieB

3. To check for dragging brakes and/or wheel bearings, release the parking brake and flip Run/Tow switch to Tow.
(The cart will beep at you and apply max Regen Braking if you push/pull it in the Run mode - Something to remember...)

Push cart by hand on hard level surface. It weighs half a ton, so it will take some effort to get it moving, but once it is moving, it should push easy and make no sounds.

4. You need to get a handheld DMM (Digital Multi-Meter).

Measure the battery pack voltage about 12 hours after the charger shuts off automatically (Doing so sooner yields an artificially high reading.)
It should be 38.2V, or thereabouts.

Drive the kids to school or take a trip of a similar distance and note miles traveled. Wait half an hour after the cart stops and measure the pack voltage again. What the voltage has fallen to will tells us the batteries SoC (State of Charge)

My cart (2008 PDS) averaged about 1.8% SoC per mile in stock trim, so yours ought not to use much more than that.

Attached is a chart to estimate SoC from battery voltage.

[hmcnav]

This may sound really stupid, but on the digital SoC meters will it read 38.2 as full and when it gets to 36 it is a 50%?

[sportcoupe]

That is exactly correct. You read the meter while the cart is stopped. Be aware that batteries "bounce back" after being run so a true reading takes 1/2 hour after stopped. You will quickly learn about how much they bounce back after having the meter for a while.

[hmcnav]

So if you are driving it for long distances and are not stopped how does it read?

[scottyb]

You will get a close reading anytime your off the gas for a moment.