I have a 95 425 magnum that is not charging the battery. It has a new strator, flywheel and pick up coil installed this pass spring.But it does not seem to be charging the battery. Also how do you check if it is charging asking to make sure I am checking it right.

 

First thing everyone asks - is the battery good ?

What's the output voltage with engine running on the regulator Red wire to ground ? It should be in excess of 12 volts DC . If not , check the stator output voltages , Y to Y/R should be up in the 30 - 40 volts AC range and the Y/Brn to Y should be about half of that , same for Y/R to Y .
If the stator voltages are good , replace the voltage regulator .

If stator output is low check the stator windings resistances { with engine off } , Y to Y/Brn should be less than 1 ohm , same for Y/R to Y/ Brn . Same wires to ground should be infinate { no reading to ground on any of them } .
If everything seems to check ok one other thing could be weak magnets on the flywheel , especially on a older machine .

 

Along with the good directions that Yooper posted especially on always checking/ load testing the battery first,check that the regulator/rectifier wires are all plugged in. The Magnum and Sportsmans were bad about having wires vibrate or pulled loose. Had plenty of them hauled into the shop only to find out this is what had happened.Especially since the regulator's at the front of the atv and subject to having wires pulled out from branches,etc. Item#39 on the parts break down.Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse