View Single Post
Old 04-21-2009, 09:53 PM
eDJ's Avatar
eDJ eDJ is offline
Motorized Bicycle Elite Member
Join Date: Jul 2008
Location: Wayne National Forest
Posts: 531
Default Re: What wattage headlight to use?

Is this light going to use a fresnel lense ? I mean a lense like a sealedbeam headlamp
on a car or motorcycle or will it be like a flashlight with a clear glass lense.

The light I'm working on will probably work more like a spotlight than a controlled
lumination light as it will just have a glass disk for a lense. I've been looking for
a small motorcycle or motorscooter headlight lense about 3 inches in diameter
to mount ahead of my bulb. It will make some difference when it goes thru that

When you look at all the little lines in a headlight lense and wonder what or why they
are there, these are like small magnifying glasses that direct the beam and intensity
of it. If the lamp has a hi or lo setting it will change the lighting dispersement. You can
measure the light on a wall with a meter to determine the lumens that fall on a graph
if you can find a large white wall. (the yellow shows the approximate single power headlamp
pattern) The high low beam of auto headlamps or motorcycles may be 45/55 watts
but in this case the lamp may be significantly less.

But if you're only using the one intensity of bulb the curve of the reflector and fresnel lense
will determine the dispersement over the path in front of you. The graph below shows
how this stuff is measured. The power of the single bulb may determine whether your lamp
is seen as high or low beam. If you are riding less than 30 mph you really won't need
a hi beam.
Attached Images
File Type: jpg ZzLamp.JPG (22.9 KB, 44 views)
Reply With Quote