Headlight Bulb

[MikeC23]

I currently have a dual headlight setup that has 2 35W 12V H4 bulbs. They are... ok at best. I would like to put something with a little more throw distance to it for the limited amount of night riding that I do. I was thinking about these: https://smile.amazon.com/Philips-X-...745153&sr=1-17&keywords=h4+led+headlight+bulb

I have a stock charging system setup with mostly new components. Do you think these would draw too much juice? Is there a better option?

 

[Paul Sutton]

If you now run 2x55W then when riding with the voltage at approximately 14V you will draw close to 8 Amps. At 2500 rpm the bike is capable of approximately 10 - 12 Amps and at 3500 rpm about 16 Amps. By the time you add in other systems such as brake lights (filament type) and ignition and alternator field winding you are approaching the limits of the system depending on rpm. I once had a friend who put spotlights on his car for night driving. The load was close to the limit for his charging system. As long as he stayed near 70 mph everything was fine but at 50 mph the lights would start dimming as the battery started to lose charge from having to supply the extra power that the alternator could not produce at lower rpm (50 mph).

You will need to add up the total power load for your bike at the typical rpm you will be traveling and see if you exceed the alternator output current. Also, you do not want to overload your wiring harness i.e. the lighting circuit and possibly the alternator circuit.

I think the better option may be to not exceed 70W which you currently know works and look to perhaps LED lighting. You will need to check what is legal in the way of LED because I see lots of warnings about their use on the EBay UK website - May be different in the North America.

Hopefully someone has done similar to what you propose on their XS and can offer a working solution. My concern is limited to current loading of the system.

 

[xjwmx]

I'm gathering your eyes have limited night vision. If more distance would fix the problem, so would slowing down so that you don't outride present distance.
I think the warnings about LED headlights were because they were weak, not sure what they're like these days. One thing I know is the more output an H4 is designed to give the shorter its life. Three different brightnesses and life expectancies is one marketing strategy.

 

[azman857]

I believe in ebay there are LED lights with fans that suppossedly draw less amps and have more lummenss(sp)/brightness than H-4 do. I've been waiting for a write-up on one myself before paying up for one.