Are revolights a good idea?

Question

I've recently seen this:
http://www.kickstarter.com/projects/revolights/revolights-join-the-revolution?ref=spotlight

Basically it's leds on the wheel + a timing mechanism + persistence of vision effect. The video on the web page shows it in action.

It seems to me that this immensely enhances riders visibility (it's really hard not to see what basically looks like a Tron Light Cycle), but I can't really judge how good is the lighting provided in terms of seeing in the dark, or if the design brings serious reliability concerns.

In conclusion, would these lights make safer than a “normal” light, or is just a costly gimmick?

Answer 1

I don't believe these are "better" or "worse" than other lights, rather they are a supplement to other lighting systems. I think the inventors' claims about forward and rear illumination are somewhat questionable as it won't compare to a real head/taillight of similar cost.

However, I think they would provide some improvements in side and off-angle visibility. They are "eye catching" because they are distinct which is a very important factor to being noticed by other road users. There are actual lights which also provides superior visibility to any reflector-based solution available on the market today. Based on what they claim (and what is visible in the videos), these will provide nearly 360 degree visibility.

Mathew's answer makes some excellent points about weight and relative brightness. However, I disagree with his point about using a reflective materials as a potentially better solution. I have used many types of reflective materials ranging from reflectors to polished metals to 3M SOLAS-grade reflective tape. When you are within the "optimal" range of angles, they provide an incredibly bright surface for a long distance. However, when viewed from an off-angle or when the light is not directly shining on the reflective surface, their illumination characteristics are relatively poor--even when using a the high beams on a car.

There are many situations where a car's headlights are not illuminating the area the driver is looking (i.e. the driver is looking left or right) and the amount of light striking the reflective surface is minimal. Products like the revolights and the down-low glow tube are attempting to solve that type of problem--i.e. anywhere that reflective materials may not be reliable and your "normal" headlights won't provide adequate visibility.

Answer 2

Yes, with easy to spot 'caveats'...

On 'Critical Mass' bike rides there are all kinds of imaginative lighting setups that give individual riders individuality. We like creativity in cycling and how everyone is different. Undoubtedly these lights are cool and would be fab on a Critical Mass ride. Therefore, for that reason 'yes'.

Caveats...

LED lights are not a focused light source unless you have some well designed reflectors to work with them. That is why halogen lights still exist on the marketplace for bike lighting - they may not have the battery life or the bulb life but the light quality is better.

The 3M company worked with Vrederstein tyres in the 1980's to create reflective tyre walls. These reflect the light of car headlamps straight back at the driver, and car headlamps are brighter than a bunch of LEDs. Therefore, to solve the problem of illuminating bike wheels, the 3M/Vrederstein solution is better.

Now for forward lighting. There used to be brackets for putting a light low down on the fork blade, many bikes used to come with a boss exactly for this purpose. However we have moved to placing the light higher up on the handlebars, not even pausing half-way to use the reflector bracket. Low-mounted lights are not visible to the car in front in the way that handlebar mounted lights are. Most riding is in cities where cars are the problem and street lighting exists, that said, the low-mounted light is better for riding trails etc. where you do need to see what is immediately in front of you. However, modern lights frequently have a lens/reflector design to put the light where it is needed from the higher handlebar position, so you can get the light where it is best suited without having a light that is mounted low down.

Clearly there is a weight penalty, a rotating mass problem, an electrical reliability problem and a 'keeping the bike clean' problem to go with the revolights, not to mention a small matter of expense.

In summary, the lights are undoubtedly eye-catchingly cool, however they are a solution in search of a problem.

Answer 3

As a Revo Lights owner I like them a lot as a second light source.

Since the light is lower to the ground they do a better job of lighting up the pavement immediately in front of you. For being seen, they're much more visible than many of the headlights and tail lights I see on other bikes out at night. Especially from the side, when you're at a stop sign or light. But even from the front and the back the spread of the persistence-of-vision effect and the light spill onto the pavement makes it easier for drivers to see you than when using point light sources. [When driving I appreciate night riders that have multiple flashing rear lights instead of a single solid rear light. The sooner I can tell "that's a bike" the happier we all are.]

That said, I've still kept my original headlight and tail light on my bike. The headlight I've got does a better job of lighting up the pavement farther down the road, which helps on roads with sparse streetlights and/or trees that block them. And the more rear lights you have the better in my book. If any battery dies mid-ride I've got a backup.

If I absolutely had to pick one or the other I'd pick the Revo Lights. They do a fine job lighting the road. They make it easier to be seen. Their novelty alone makes folks pay more attention. It absolutely positively has nothing to do with being impressionable when Tron came out (ahem).

But if I started with Revo Lights, I'd probably still get a second headlight to shine a little farther down dark roads. The better to see potholes and unlit night joggers.

Answer 4

I am also a long time Revolights owner. I love them for the visibility they give me, both front/back and side-on. People I talk to say that their eyes are drawn to the Revolights when they're spinning. They can't not look at them! The front lite is not quite bright enough for my city commuting, although on a dark road/path they are perfectly fine. Installing them is a bit of a chore and their wheel options are somewhat limited. They need more work on the software on their bluetooth enabled batteries, but you really don't need the bluetooth features at all, they are mostly frivolous. I live in Seattle, which has a pretty bike-aware populace, but I also commute on a really busy road, so I tend to have a close call every two or three years. I've had my Revolights since the first Kickstarter in 2011 and I've not had a single close-call at night since then. I believe they are worth every penny.

To supplement the Revolights, I also have a set of Magnic Lights (https://www.magniclight.com/en/). These use no battery and have a contact-less method for generating power from the wheel rims. They provide the extra light I need on partially lit roads and paths. They produce no noticeable drag on the wheel! I'm serious. I tested them on a wheel in a truing jig, spinning the wheel up with a drill to get consistent speeds, and the wheel spun for about 5% fewer seconds with the Magnic lights harvesting power than without. Their only drawback is the limited mounting positions. In order to generate power, their power-core has to be positioned within a 1/8" of the wheel's rims. I had to improvise a mount on my front pannier rack to get them forward enough to not be blocked, but once I got mine installed, I've had no problems with them. They are super reliable, bright enough for my needs, require no batteries, and five minute of riding actually builds enough power to keep them lit for a minute or two after I stop moving.