Wiring a car headlight for a bicycle

[Thxcuz]

I'm wonder if I can wire a car headlight for battery power a bicycle. I'm looking at something like this
http://www.harborfreight.com/12-volt-ha ... 93904.html

I would like to use the light as is and not convert it to LED.
Thanks

 

[milbums]

I would like to use the light as is and not convert it to LED.

The biggest problem with using the light "as is" would be battery life. LEDs use much less power and can run for hours on a couple of double A batteries. The light pictured would need a 12 volt battery (large, heavy, expensive). Not saying it can't be done, just not an efficient option.

 

[Thxcuz]

Fair enough. I have other options

 

[LukeTheJoker]

You can buy replacement bulbs that are led and just fit straight in the back, no modifications necessary...

Luke.

 

[alecw35]

It takes a H3 bulb. That's a standard fitment.
Ive had a quick look and theres bulbs rated at 55 watt. That's 4 amps of current they take, at 12 volts. 55 divided by 12, is just under 4.
If you look at batteries, motor bike and car batteries are rated in Amp/hour. So for instance you get a 20 amp/hour battery, that will last for 5 hours. 20 divided by 4.
Some motor bike batteries are quite small. You can get Gell filled batteries, that are sealed, so don't need to be mounted upright. They are smaller than Lead/ acid batteries. But can be expensive.
Regular dry cell batteries would be hopeless with such a high wattage bulb. Even rechargeable batteries, Nicads and NimH cells.
I did see LED H3 bulbs. ok they look horrible. But it says its 3 watt. So easier to keep it running on battery power. Should just fit into the headlight. No mods needed

 

[Alsfelt]

Best bet is to fit the light you want and make a regular flashlight bulb fit in it. LED if you choose. Gonna take a little bit of work but the battery issue will be solved.