1999 Suzuki lt500F won't rev up

[Mojoman]

I have a 1999 LT500F quad. When you hit the throttle it won't rev up and back fires. The weird issue is when you hit the starter button the engine revs up perfect??? Is this a wiring, surge issue or part malfunction?? Any help or recommendations will be greatly appreciated. Thanks

[Mech]

It will be a problem with the charging, the regulator operation in particular. If you turn the headlights on you will probably find it makes it slightly better too.

Check your battery and charging.

[Mojoman]

I believe it's the rectifier. It's pumping 17 volts back to the battery. When the lights are on it runs perfect. I ordered a new 1

[Mech]

You should check the regulator's earthing wire..  That could cause it.