Semi-dim headlight for visibility
 

Coming back bike rider and somewhat experienced electrician. In terms of electrical, I've done a small amount of circuit soldering, worked some on automobile electrical lighting and wiring.

I would love to have one of these UPS rounded headlights. Mounted on a bike, I imagine this would be very visible. On the back of the bike, add one but in a red color. Assuming the back has a Hi/Lo setting, run it on low. And then, attach the back light to the brakes, so that when either brake lever is tapped it will put the back light on Hi.

I'm guessing this is probably a 50- to 100-watt light bulb, mounted inside of a glass housing (dispersing the light) with reflector (?) around the bulb. I'm not thinking so much of a light to see in the darkness (although these lights look sufficient) but as a light in the daylight that will stand out from 50-yards away, or quickly catch attention in a rear-view mirror (while avoiding going so far as to blind the viewer).


https://cimg6.ibsrv.net/gimg/bikefor...2eefed4f66.png

UPS rounded headlights


How about one of these: Sylvania 14818 25-Watt Incandescent R14 Mini-Reflector Light Bulb?

How hard would it be to, on a budget, attach this to a pack of rechargeable LiPo 18650 batteries? Or a power bank like this product: Solar Charger 24000mAh Portable Power Bank, ALLSOLAR External Battery Pack?

In terms of usage time, according to this website the energy of a single 18650 is 3.7*2200=8140 milliwatt-hours. So two would be about 16 watt-hours. Four would be 32 watt-hours, enough to power the above 25-watt light for about a one-hour ride. I'm actually looking for about two hours worth of riding on a single charge (45 minutes there and 45 minutes back = 1.5 hours). Two hours would be 50 watt-hours for the above 25-watt light. So that would require about eight 18650 to have a comfortable margin (64 watt-hours).

Are there any recommendable drive wheels (e-bike hub motor wheel) for the front tire that provide enough watts to keep the battery charging up along the ride? How difficult would it be to pipe the power from the front motor into the power pack, of which is powering the light? Or better yet, siphon the power off the tire directly to the light and even it out with power from the power pack, sending excess power from the tire to the power pack (whenever excesses might exist).

Just my opinion but it sounds like an awful lot of work, both in putting it together and in energy required during operation, to be seen. There are very bright flashing headlights that will make you very visible for little money and not require hauling around heavy lights, batteries, etc.

Sounds like a fun project but totally unnecessary in my opinion.

I think another fun idea would be a low-power version of the UPS headlight. Something in the range of 2-4 watts would be great. I'm thinking along the lines of a LED backlight (example 45mm x 86mm product with ~3V at 20mA, which comes out to 0.06 watts - https://www.adafruit.com/product/1621). Could this scale up to the size of the UPS light, let's say 12" x 6" rectangle. I'm guessing this would be somewhat visible.

In terms of aerodynamics, angling two of these 12"x6" flat lights ought to improve the airstream, maybe at a 30-degree angle (arrow-shaped).

I've noticed most bike lights are measured in lumens. How would the intensity of the LED light compare to most bike lights? (Again, for this application I'm looking to be seen, not to see.)

Wasn't this already addressed in the other thread?

https://www.bikeforums.net/electroni...t-wattage.html

Yeah, to a large extent. I thought that the UPS headlight was a different take on it and was wondering if someone had specific ideas to create this.

At this point, I'm kind of leaning more toward creating a thread that would address an LED light such as this (https://www.adafruit.com/product/2894 - Camera-Mount LED Photography Light - CIE Ra 95 - 3200K to 5600K). Ideas for a quick mount / unmount carry-with-you system for a light + battery pack system.

As one of the other posters already alluded to, there is no need to mess with something like a motor vehicle sealed beam headlight. Just go to any local bike shop and tell the people there you want a lamp for riding in the day. What you want is something that will flash with output in the 100-200 range ( although this is not for use for daytime paved trail use, road only ). Point being made; a bright flashing light will get you seen.during the day faster than any type of steady light. If you've ever seen anyone using a flashing light in the day you know this is true. At dusk or night the 100 or 200 would be too bright so this is only for day. No need to make the issue more of a problem than necessary by building something designed for a car. There are already plenty of bike light products available for bike use that will work very well whether you want a front light or a back light. If you are insisting on something wide and big there are already several types of bike lights ( both front and rear ) that utilize wide COB panel LED's. You just have to do some searching. Ebay and Amazon are a good place to start.

Here's another one: (https://www.amazon.com/gp/product/B017B76D1O/). Not sure about going to a local bike shop. Here is REI online: (https://www.rei.com/c/bike-lights?r=...-lights&page=1). Not seeing something like the aforementioned product.

Thanks for your comments in the other thread, by the way.

I suppose there is this: (https://www.rei.com/product/109692/l...ont-bike-light), which looks to match at least the physical dimensions.

Only light with huge reflector and low glare is the Supernova M99 series. It can be used with any DC power source delivering the needed voltage and current.
https://supernova-lights.com/en/prod...lights-45-kmh/

I am pretty sure that the UPS truck had standard 7 inch round headlamp. In USA those were usually a sealed beam decades ago, other countries often allowed a better quartz halogen headlamp with replaceable bulbs. Motorcycles also could run the quartz halogen 7 inch lamps with replaceable bulbs instead of sealed beams. I used a good quartz halogen headlamp on my vintage motorcycles, I think the ones I bought were Hella brand. Wattage was 55 watt low beam, 65 watt high beam, Bulb had two filaments, only one filament was used at a time, either high or low but not both.

The exercise bike at the gym and also the stair master suggest that I can produce about 120 to 140 watts on a continuous basis, which is a bit over double what one of those lamps would draw. Do you still want to try to power two of those lamps with pedal power?

You seen to be fixated on using something humongously large when it's not needed. Today while driving through the rural backroads of northern Maryland I saw a cyclist riding on one of the rural two lane highways. As he was approaching me from the front I first noticed him when he was about a quarter mile away. What caught my attention was his front blinking light. Late in the afternoon, I would estimate his lamp to be about 100-200 lumen. His lamp was just a normal torch type typical bike lamp. Like I said before, sold almost anywhere. Almost forgot to mention, after we passed I looked in my rear mirror and noticed that he had a very bright rear LED lamp as well. Likely something in the 100-150 range. I don't know what brand it was but it was at least as bright as my Cygolite Hotshot 150. Point I'm trying to get across' " You don't need something huge to get seen". With the right output and the right optic, you will get seen as long as someone is either not distracted with their phones, drunk, doped up, half blind or any combination thereof.

Keep it simple. Get a Light & Motion Urban or Deckhand light - same thing. That specific type of barrel is ideal for this homemade rig.

Besides being a good all around light the L&M has reasonably flat discharge characteristics, decent battery life per charge, and the older models had a pulsing rather than strobing type option. Opinions differ about which is better.

These lights can be strapped to most handlebars, head tubes, some forms, and road bike helmets without special accessories.

Then get an empty pill bottle made of white translucent plastic, usually HDPE. It's soft, easy to cut and trim with a craft knife, pocket knife or scissors. And it's tough and durable.

Cut the bottle to fit the notch in the light barrel behind the lens. It should snap in securely yet be detachable without damage.

Trim the shape of the hood as desired. Mine directs most light where it's needed without blinding oncoming cyclists or pedestrians. It can also be rotated to light the road ahead at longer range with less spill on the bike and road directly under the bike.

I used black Gorilla tape to shield my eyes, while leaving some white plastic visible on the sides to enhance side visibility. This is ideal for handlebar mounting but not necessarily the best for helmet mounting.

Besides enhancing side visibility the bottle hood creates a larger diameter apparent light source as seen from the front.


https://cimg0.ibsrv.net/gimg/bikefor...a7ef093f84.jpg

Completed assembly of hood on Light & Motion Urban 500.

Here are the basic components. Pretty simple and cheap. A bottle of ibuprofen from the dollar store.

NOTE: This works best with a perfectly circular cylindrical barrel like the L&M Urban lights. It can be done with others but it'll be a PITA. You'll need to bend the translucent white plastic material to fit the squared off or oblong shapes of other lights. Then find a way to secure the hood. And it won't snap in and detach as conveniently.

Get other lights if you like as your main headlight. But for an excellent all around to-see and to-be-seen light, it's hard to beat the L&M Urban type, especially if you want to add this kind of homemade hood/diffuser.

https://cimg7.ibsrv.net/gimg/bikefor...6353e74979.jpg

The hood I'm using was cut from a slightly larger bottle than shown, but the same type.

Please understand: Large is not better. A sufficiently bright beam will appear to come from a larger lamp than it actually does. Size is nothing unless it helps create a bright beam. Some very effective lights are insanely tiny. Size does not matter.

The bike lights industry has responded to many of our needs. It is mature enough that you are unlikely to home-brew something better. Just buy an existing product. You're thinking too hard.

In the end, if you're going to cobble something together that functions like a car headlamp you have to consider if the means is really going to justify the end result. If you think having a headlamp that looks like a car's headlamp is going to make you safer than someone else who is just using typical bike lights I would have to very much beg to differ. I had a coworker who got killed riding his motorcycle ( in the day ) through an intersection. The fact that his headlight was on didn't save him. Today, with the full plethora of bike lamps available on the web, it makes no sense to DIY a lamp for your bike unless that is just something that is a hobby with the end product being a very custom and refined setup. What the OP is asking or talking about doesn't indicate that he is a skilled hobbyist. If he was there would be no need to ask any questions.

If I was riding through a busy intersection during the day as a cyclist I have the advantage of being able to run a flasher. Actually I have three options. I can run a 60 lumen mini-flasher, a 200 lumen steady light with one second pulse/bursts or ( if feeling really threatened ) I can run my Gemini Duo on flash ( 1500 lumen ) with the option to use the remote control for manual bursts. All things considered, I think those are better options than having a clunky car headlight mounted to the bars but what-the-hell-do-I-know....:rolleyes:

Lumens are the total Luminous flux of an lightsource.
Intensity of an lightsource is Luminous intensity, measured in candela.
For your application i do recommend the Cateye Rapid X3 (TL-LD720-F).
cateye.com/intl/products/safety_lights/TL-LD720-F/

In my opinion, having owned a whole darn bunch of lights, the lux measurement and beam shape are the most important characteristics of any headlight I personally would want to use.

Ed Kearney, call your office!

Reductio ad absurdum:

https://cimg0.ibsrv.net/gimg/bikefor...764bc7f6da.png

Off to the 3D printer to fabricate a mount!

Big enough? https://www.amazon.com/Headlight-ELO...KJ1KAYZ3PD4XKH

I just bought a fairly powerful daylight visible headlight at RIE for $16. It was on clearance and normally sells for just under $40. It would be hard to build this myself for $16.

But assuming you want a DIY job the ket technologies are
1) LED lights
2) efficient reflectors
3) LiPo battery and charge control from USB carger
4) heat sinking and monitoring
5) over all control

The lasts done with a tiny micro controller and software. LED brightness is control by PWM (varying the duty cycle of a square wave) LEDs are rated for a given "average" power and you can use that as a steady state "solid-on" or as a bright glass followed by a longer "off" period. Or some kind of compromise. The little computer inside also measure the LED's temperature and adjusts power to keep in under a limit.

None of this is rocket science but how many enf=ginerringhousr will you burn to save $16? I can't buy the parts for this headlight for $16.