Trial and error?
 

Hello guys losing my mind at times with my cart. It’s a 1997 ezgo txt. I’ve lifted the cart on 23 inch tires and a back seat. Relathed the motor, 200amp solenoid from Scotty B, 2 gauge battery/motor wires and brand new 6 volt Powertron batteries.

At the movement there seems to be nothing getting hot after I upgraded the wires.. now I’m confused with my power/speed. There are times where my cart wants to fly on flat 19-22mph after a full charge. Then there are times where it’s more mellow and rides in the 14-16mph after a full charge? With all being replaced the only stock items are the controller and f/r switch.

Pre solenoid upgrade/2 gauge wires the cart would cruise upwards of 20mph but the stock solenoid/wires would get very hot and even smell. Now that I’ve upgraded those items why am I not seeing the same speed results

Re: Trial and error?
 

My initial guess....or suspect would be the F\R switch. If you had the solenoid heat up you may have had some heating of the F\R switch.

When the cart runs slow.....have you stopped just to see if your F\R is unusually warm or have you checked the cables for any sign of heat\melting?

Re: Trial and error?
 

If it is a series drive, next time it decides to run slow, stop and shift the F/R to reverse and then back to forward two or three time. Then make sure it goes all the way to the mechanical stop the last time you shift into F.

The 23" tall tires are going to make the motor draw a lot more amps and the stock F/R isn't up to it. Ought to be a HD F/R from Scotty or a reversing contactor.

Re: Trial and error?
 

Install a reversing contactor and never look back!!

Re: Trial and error?
 

I had 2 different wire kits the first set were only batteries and the controller. The rest of the wires got super hot. I ordered the 13 wire kit and installed it last night and no wires got warm the solenoid was cool. I’ll take it for a longer drive and see what happens to that f/r switch.

What’s the difference between the f/r and reverse contactor

Re: Trial and error?
 

The main difference is the way the internal contacts make and break, or turn on and off. Electrically, they both do the same thing. Both are break before make switches.

Mechanically, an FNR rotates four studs with two bus bars 90°, to break then make.

A reversing contactor uses the same type of connection as your solenoid, namely it pushes the contacts together to make, then allows a strong spring to break the connection.

Both are prone to arcing if switched under load - which you shouldn't do - but the FNR adds friction to a soft material, so over time, the contacts wear, which causes resistance, which causes heat. A fairly common failure mode is for one or more studs - contacts - to heat up enough to soften the stationary part which holds the studs. Once softened, the studs become looser, which causes more heat, which soon results in failure to make contact.

Re: Trial and error?
 

Okay so with all that has been upgraded once I get that reverse contactor in I’m gonna start seeing more power to the motor and I’ll be back in that 19mph range?

Re: Trial and error?
 

Doubtful. Unless you are dissipating a LOT of heat in bad connections somewhere, WYSIWYG.

EDIT:
Note my sig. My ScottyB HD FNR does just fine.

Re: Trial and error?
 

The hd f/r and the reverse contactor seem to be a difference of what $30? After I change out the f/r the only stock component is going to be my controller guess the way this has been working that will probably be upgraded as well.. still baffled on where 3-4 extra mph appear and disappear from time to time

Re: Trial and error?
 

Plug up your laptop and do a datalog when this occurs. That will tell you what the throttle signal is.

I'd recommend eliminating the Molex connector on the throttle cable. Intermittent bad connections can cause problems between the ITS and the controller.