Topic: Conversion of headlights to LED

Product: ADVmonster H4 R3 LED Headlight

Vehicle: 2005 Yamaha Bruin 350 ATV

Difficulty: DIY, measuring, cutting to size, wiring involved

Summary: Conversion of the headlights has reduced power consumption while increasing the light output and reliability.

ATVs (all terrain vehicles) generally have lighting systems that are an after thought.  Primarily offroad vehicles should have great lighting, in the event you are out after dark it will likely be in a poorly lit area.  

Stock Yamaha bulb and socket (bulb has high and low beam)

After a few measurements of the id of the bulb socket and the od of the H4 R3 base, it was determined the 2 would fit together to make a holder for the led bulb.

Disassebled bulb holder

Cut back end of bulb holder (no turning back now!)

Check for light element depth, attempted to match stock location, H4 R3 shown next to cut bulb holder

H4 R3 base cutout 

H4 R3 base cutout next to bulb holder

With a bit of cutting to size, the H4 R3 base fits in the bulb holder

Profile view

Installed - back of ATV headlight

Result is awesome - light beam has an upper cutoff for traffic and a high beam that really reaches out.

Yellow light is stock halogen, white light is LED