Custom bike headlight (help?)

Hey everyone, I've been pretty much lurking here for a few months now, but now I'm looking for some advice... I'm going to be modding a headlight for my moped for commuting after hours, mostly on pavement, but sometimes not... I picked up a body for the light off ebay (waiting for it to arrive) but obviously a 2 x AA "high beam" isn't going to cut it. ebay pics. I can wield a soldering iron, and have access to a full machine shop, so wiring, mounts or other hardware are no problem, but I need to figure out what bulbs & batteries to run, and figured you all would be the right people to ask... /ubbthreads/images/graemlins/bowdown.gif My current thoughts are to go with a cyan LED(s) (luxeon star, 1 or 5 w maybe?) for the low beam, for use with well lit roads, and wire them with a (switchable) blink mode for daylight/twilight running, and have a high beam with, say, a 10w or 15w halogen? I can build a battery pack to mount on the frame/under the seat somewhere, but battery cell ideas and sources would be very cool... I'd like as long a runtime as possible, at least a couple hours, and since I have a 2 hp motor helping me pedal, weight isn't a huge factor... I'd much rather carry a few pounds and see where i'm going at 30 mph /ubbthreads/images/graemlins/grin.gif Lotsa light is good, but I shouldn't blind all the cars on the road either... Also, I don't mind spending what it's worth for this project, but cheap is good. /ubbthreads/images/graemlins/buttrock.gif
I'll take some pics of the bike and link em when I get some time... Thanks!
Cougar

A 5w star using the LED Dynamics driver is the way to go. I'm using that combo with a 12v, 4.5ah water bottle battery. The light output is great - good for 20+mph and I get 8-9 hours run at full brightness. I'd guess it's about the same as a 15w focused halogen, maybe better. The LED driver is a bit big but if you need to you can (very carefully) break off the metal mounting tabs to save some room. Just be careful, the leads are real close to the mount tabs and it's easy to cut one off so close to the epoxy shell that it can't easily be repaired.

You'll need plenty of heat sinking as well. I mounted the star and 30mm optics in a section of PVC pipe then used a grinding wheel to cut a CPU heat sink to a 40mm round shape and mounted it to the back of the star. It's exposed to air for better cooling.

I checked the heat buildup and the 40mm is OK so long as it's getting a reasonable amount of air flow, otherwise, it gets quite hot after about 10 minutes. Great light - I hope the star holds out, since the light is mostly cemented together it will be a pain to repair if it blows.

I went for a 2 hour ride with it and the only time I felt I need more light was on fast down hills when I kicked in a 20w halogen to help out, but I was hitting 35+ at the time.

Al

Hi Cougar,
Welcome to CPF!

I don't know what kind of moped you have, but the ones I've had all used power genereted by the engine... (I have owned over 20 ... /ubbthreads/images/graemlins/eek.gif ) are you sure you need a batterie-pack?

An LS will not have enough throw for the speed you are going, you will need an incandescent for that. I used a 5/10 W high/low beam that worked well for me.

Hope this helps a bit, I'm sure you will get better responses /ubbthreads/images/graemlins/tongue.gif

Bike pics

I got a few pics of the bike, i've been riding some trails today, so it's still muddy...
Pic index is here: http://www.geocities.com/[email protected]/moped.html
Fixed: Pictures work now /ubbthreads/images/graemlins/grin.gif

Re: Bike pics

Well, it seems your site has exeeded the allocated data transfer. /ubbthreads/images/graemlins/frown.gif
ImageStation usually works well for me, there is a thread on how to use it. /ubbthreads/images/graemlins/wink.gif

How to post pictures.
Hope this helps,