Halogen mountain bike lights >> help needed

[kro]

I have been pricing these up, and most places want to take 300+ dollars off me, for a single halogen light, often with crappy sealed lead acid, or nicad batts, with the more desirable NiMH being even pricier.

I was setting off to make my own, but thought I would ask if anyone around has any old ones they would consider selling to me, just in case. Even if its the ligh unit, with a stuffed battery back, I can still work with them. Even just the light unit, with no cords or anything, I would consider.

I am looking specifically for Halogen lights, the LED ones cast a hazy indistinct light, unless you pay for the 700 + dollar ones (crazy)

I came down the Barnicoat range last night at 7.30pm, and couldn't really see shit, so I'm on the warpath now.


Thanks KB, have a great Easter.

[skelstar]

Spent a lot of time in the last playing with Lead Acid batteries, plumbing pipe and Dichroic lamps that you can buy from lighting stockists. Buy the 20W 35mm ones.

I say: have a go at making your own. I'd take some photos of mine for you if it helps.

[kro]

Some more detail would be great thanks Skels. I have a rudimentary understanding of electrical stuff, and more than enough tools to make up light pods etc, and would be more than happy to have a crack at it. Any pics for ideas would be great thanks matey.

[skelstar]

No worries, pics might have to be tom (or Tues if lights at work).

[bobsmith]

Fuck for that price, get yourself a lithium polymer batteries from some RC stockists and a lipoly charger... will last much longer than NiMH for the same weight.

one is:

http://www.wattsuprc.com.au/product_list.asp?cid=10

[kro]

I am happy with the NiMH's thanks bob, I have never heard of LiPo before. I Can get NiMH's cheap as from Tardme, and it's only for a small light set for the ole mtb, so I don't want to go too techo. I am going to read up on these LiPo's though, they sound rather interesting.

[bobsmith]

Indeed. If the weight matters to you it's the way to go.

Lipos are made so that each cell is 3.7volts nominal so a three cell pack would be around 11.1V nominal. I have a 2000mAh cell here which weights not more than 140 grams or so which with NiMh batteries of that capacity it will weigh more than 250g.

Hmmm now that I say that perhaps that wouldn't matter so much with mountain bikes........

[skelstar]

Used to lug around a couple of 2.2Ah Lead acid batteries. Hardens you up eh? :yes:

[MisterD]

A couple of guys I know made their own, using plastic tow-ball covers as the light pods, helmet mounted with wiring running down to batteries in a belt.

I'll check what they're using for the lights themselves.

[kro]

Thanks, any info is appreciated.

[bobsmith]

I'm really interested in how this comes out too... I'm thinking about using my bicycle for commuting as I need to lose some weight but I'll need some decent lights before that....

[kro]

To be honest bob, if you just need safety lights, any of of the cheapo Trademe LED ones will be brilliant for the job. I have one LED cycle light, which i paid 14.50 for on Tardme, and the other night, I rode to the top of the Grampians in Nelson, which is 45mins bike trip, and phoned my wife once I was on the summit, and asked her to look for the flashing light, which she spotted within about 2 secs of looking. The thing with them is that they have intensity, but the cheaper ones don't light the road like a car headlight will. I need something to light my path, so I can boogie on the downhill, and generally not end up tangled in fence wire.

The cheapo ones for safety lights are perfectly fine dude.

[twinkle]

my brother got one of these bulbs (i think it was 20W though) http://www.dse.co.nz/cgi-bin/dse.storefront/4616bf0301159212273fc0a87f330641/Product/View/S8456 and put it in the end of a plastic pipe, then fixed it to the handlebars. We did that 12hr race in taupo a while back and it worked a treat.

[bobsmith]

yes........ but there's just something about things I make with lithium polymer batteries........ Mmmmmmmm

[skelstar]

Plumbing fittings (pipes and end-caps) are the way to go. Also, take a slice out of the pipe and cut a section out and use it as the mounting mechanism. I better take some pics.

[kro]

I work for a place with lots of plastic pipes, so that was my plan skel. Thanks for the link twinkle, what sort of battery power did you use for that?. Thats a high wattage bulb, and quite high voltage too for a bike situation.

I'm gonna find some conversion charts I think.

[kro]

AH = AmpHours.

1 AH = runs 1 amp (current) for 1 hour.
So basically the capacity of the battery.

You can (roughly) work out what you need using the following:

Bulb wattage divided by battery voltage = current drawn.
Then Battery AH rating divided by current drawn = run time.

For example:
50W bulb, running on 12V battery draws 4.16Amps (50/12).
So using a 7AH battery will give a run time of 1.68 hours. (7/4.16)

Like I said this is rough, in practice your run time will be shorter than the theoretical one.
I think you get about 1:20 out of a 50W running off a 7AH?

Hope this helps and isn't too confusing...

[twinkle]

what sort of battery power did you use for that?. Thats a high wattage bulb, and quite high voltage too for a bike situation.

We had a sealed lead acid battery we put in the drink bottle cage, I can't remember how many amp hours it was though. Like I said I think it was only a 20W bulb, maybe 15W even, but man was that thing bright :first: