All of the current charging stators in today’s UTVs will produce a maximum of about 35 amps of power when the engine is running at 5000rpm. Many such as the Yamaha Rhino produce less than 30amps.
Battery discharge state at an idle
Understanding this simple fact it is easy to recognize the need for adding a second battery. For example one of the most common accessories is a winch. A common 3000lb winch pulling a 500lb machine through a little mud will drain your average ATV battery in about 3 minutes. If you leave your rig idling it may take 4 minutes.
Unless you have an upgraded battery a single winching session can destroy the reserve capabilities of your battery making it useless for winching or hard starting in cold situations.
Another situation that is common is adding a couple of spotlights to your rig. A couple of 55 watt bulbs being used along with the normal lights and running functions of the vehicle would render the vehicle into a battery discharge state at an idle.
Here is a testimonial from a Yamaha owner
“Here is my story. My brother and I had killed a nice moose just before dark one evening and I had pulled my 4wheeler down and turned on the auxiliary lights along with the headlights to see to dress out the moose. I left my 4wheeler running as to not run the battery dead. We spent about 45 minutes dressing out the moose.
When I went to turn the 4wheeler around it stalled. I turned the lights off and went to start it. SHIT! The battery was dead! We were about 6 miles from the road and the pickup. 2 hours later we had walked to the truck. Now it was another 50 miles back to town to borrow another 4 wheeler to rescue us.
Well to make a long story a little shorter it was just getting light when we finally made our way back to my 4 wheeler with jumper cables to start it. Of course my buddy just had to rub it in! I shot back and said “your next”!
He said it would never happen as he was smart enough to have put a dual battery management system in his rig using a TRUE Dual Battery Kit which would insure he always had sufficient charge in his starting battery to start the engine. I guess you know the rest of the story…
I’m now fully prepared thanks to this kit and my lesson learned the hard way!
Harold W. , Sandpoint, ID”.
Trouble with adding accessories
A stator that produces 35 amps at 5000rpms will produce about 6 or 7 amps at an idle. This is usually just enough to provide for the functions of the engine running and the basics on the vehicle. Add accessories and your asking for trouble. This is such a common problem that the manufacturers are aware of that many of them actually have a second battery compartment built into the vehicles.
For example the Polaris RZR and Rangers all come standard with the extra battery compartment for car battery management system. It is the dealer’s responsibility to educated buyers of these potential problems and provides solutions like the double battery system.