DIY HID type light for ($60

Super Bright DIY Bicycle Light

If you are interested in a super bright bicycle light.. here is a bill of material list to construct
just that..

Using some useful information obtained from www.bicyclelighting.com, I settled on the following
setup.. with the back bone of the setup.. the SOLUX 4700K 35w 10 degree MR16 bulb --
Q35MR16/CG/47/10 Eiko Solux stock number 35001 (made in Japan)

Please note.. the author of the bicyclelighting web site like to say he can buy replacement MR11 and
MR16 bulbs for around $1.50 to $4.00 respectively..don't bite on this. The quality of these bulbs
puts out a dull yellow light. But at the $1.50 price.. I would overvolt the bulb by 30% to get a
pleasant light if I were to go this route.

On the other hand, the characterics of the Solux MR16 bulb is remarkable. At 4700 Kelvin, the bulb
puts out a "whiter" light than a HID bulb. A typical HID light operates in the range of 4100K and a
standard MR11 or MR16 lamp runs at
3000k. Based on what I read on the Solux web site, the higher the Kelvin.. the brighter the white
light..Do your own research.

With the Solux lamp, I have a viable alternative to a HID light -- without the HID bulb efficiency.

Bicycle Light / Vendor / Cost 1 Optronic Competition Driving Light QH-7CC JCWhitney $15.00 2 Solux
MR16 35w 10 4700kelvin bulb Bulb source 8.00 3 Inline 5.5 od 2.5id jack Radio Shack 2.50 4 Inline
5.5od 2.5id plug with power cord Radio Shack 2.50 5 Thumbwheel Switch Home Depot 2.50
3001. Weather Resistent Connector Radio Shack 2.50
3002. 12v 7ahr SLA battery Rage Battery 11.00 - TOTAL COST: $44.00 =

Add roughly $7.00 for each item that is purchased from separate vendor if done through mail order.

3003.The Optronics Competition Driving Light is a surprising good looking chrome light housing. I
removed the standard 50w 24 degree MR16 lamp and replaced it with the Solux Mr16 35w 10
degree lamp.

3004.I soldered an Inline 5.5mm o.d. 2.5mm i.d. jack at the end of the lead wires coming out of the
Optronics driving light.

3005.I constructed a power cord from a regular indoor lamp cord (SPT-1)..and solder an inline plug
that mates with the inline jack on the Optronics headlight.
3006.I installed a typical inline thumbwheel lamp swith on the cord. Since this switch is not
waterproof, I cut up a 2" piece of old narrow inner tube and slide it onto the cord to cover
the switch. I wrapped the ends of the inner tube to keep the water away from the switch.

3007.On the other end of the power cord, I soldered a weather resistant 2 conductor polarized
connector. Like wise, I soldered a mating connector coming from the SLA battery terminals.
Because of the weight of the 12v 7ahr SLA battery (7#), I place the battery on my Topeak rear
rack. I placed a 3" x 6" strip of adhesive back velcro hook fabric directly on the rack. I used
a 3"x6" strip of adhesive back velcro loop frabric on the SLA battery. I used a stretch cargo
net to further secure the battery to my bicycle rack. This battery isn't going anywhere.

RUN TIME:Your results may vary.. but here is what I've gotten.. (run time results were
disappointing) I had two 5 year old 12v 7ahr battery left over. I was able to charge the battery to
13.4 volts. I was able to get 50 minutes of run time of brilliant light, and 20 minutes of
diminishing light. At the end of the run period, the internal voltage reading on the battery was
3007.1a. The outside temperature range from 30 to 40 degrees. Each of the two batteries had similar
run time results. Test period: going on three weeks.

Based on the laws of DC current, I should be able to get around 90 minutes of bright light from 35w
lamp (roughtly 3 amps draw) using a 12v 7ahr battery. Maybe with a brand new battery, I should get a
run time of roughly 2 hours.

Handlebar mount:

I had a old Cateye HL500 headlight left over. I removed the spacer (quick release bracket) that is
screwed on the underside of the head light and bolt it onto the Optronics bracket. I now have a
completely quick release assembly for the light.

To secure the power cord to the frame, I use the velcro reusable cable organizer tape / strap.

NO FOOLING.. My bicycle light is as bright as the Lexus HID lights.

Much obliged. Nick Lee Sparks, NV carless since January 2000.

NOTE: For those who say this is too much light.. then I suggest buying a front rack, and using a
4D spot lantern secured on the front rack with a cargo net. The extra large reflector put
on an amazing amount of light. If using 4D rechargeable batteries, I replace the standard
bulb with a HPR44 (4v 1a) halogen PR bulb. If using a 4D alkaline batteries, I use a HPR36
(5.5v 1a) bulb.

I use this set up with two Cateye EL100 white translucient LED light on my handlebar.

Don't mess with the Cateye EL300 -- save your money ( I bought two of the EL300 when Performance
sold them for $25)..

This light is not a good-to-be-seen light. Because of the flat lens plate and the internal optics,
the light is shot straight forward.

However, only drivers coming DIRECTLY at YOU will see the illumination of this light. Do your own
test.. shine the EL-300 directly at a mirror.. and point it at yourself.. Move the light around a
few degee from side to side or up and down.. You will see what I mean.

For me.. this light is dangerous if used as your only light. Other than extra long run time, this
light is no brighter than a 1.5w 2c cell Cateye HL500.

Simply put, the marketing hype for the EL-300 light does not deliver.

Better solution: Buy two Cateye HL500 or the HL1500.. drill a hole on the underside of the case..
Solder a 3" power cord with a inline jack to the internal battery connector. Replace the existing
bulb with the HPR36 halogen bulb. Construct a power cord as described above.. Hook up the light to
the external 6V battery pack ... With two HPR36 bulbs slightly overvolted.. you will have
illumination as good (better) than an overvolted 10w $20 MR11 Niterider bulb.