I’ve been using both of these taillights for a while now. Vik did an excellent comparison between the two lights a while back. Kent Peterson has also reviewed the superflash and the Radbot.
I’d agree with Vik that the Radbot is bulkier than the superflash which makes it a bit of a pain to mount. You can also find plenty of evidence on the web that the Radbot is much brighter.
I was curious about runtimes. Portland Design Works claims a 15 hour runtime on steady whereas Planet Bikes says about 100 hours (presumably on flash mode).
Here is a time lapse video of the two lights.
The lights started running at 8 pm, the video starts at 9:30, one frame per about 6 minutes, and the Radbot cuts out between 1:19 and 1:25 am, i.e. about 5.5 hours runtime. The superflash was dim but still lit after 12 hours. Both lights were running freshly charged Duracell AAA rechargeables, specifically the low discharge precharged versions with white tops are that allegedly the same as eneloops. The video is only about six hours long because I’m still figuring out the quirks in CHDK.
Conclusion? The runtime on the Radbot is somewhat shorter than advertised. This is certainly consistent with my experience using it on flash mode on my commuter. Every couple of weeks, it goes into a low battery mode where it turns off, and then when I turn it back on, it will stay lit for something around 5 minutes before dying again. In comparison I don;t have to recharge the superflash more than a couple of times a year.
There is also a question as to how bright a taillight is useful. I would go mad if I was following either taillight on flashmode, and the PDW is almost blindingly bright on steady. I know that randonneurs prefer to run their lights on steady mode, and I’d be interested to know if their runtime experiences with either light are consistent with what I’ve found.
UPDATE:
Jim raises a good question about reproducibility in the comments thread, so I reran the test with both lights using a different set of batteries: Sanyo Eneloops. Although the time lapse failed, by intermittent observation, I saw that the Radbot cut out between 5 and 6 hours, and the superflash lasted more than 12 hours, so the results were qualitatively the same as before.
SECOND UPDATE:
Kent Peterson ran a battery life test of the RADBOT 1000 versus the new Planet Bike Superflash Turbo (1W). He got about 6 hours of life on steady mode for either light, which is in line with what I measured. Bottom line: if you need light on steady mode overnight, use the 0.5W superflash, which is good for 12 hours.
Great research and questions here Jun. I’ve been using both lights myself for some time (incl. this winter which has been pretty harsh so far) and haven’t noticed the PDW Radbot 1000 needing recharging that soon. I run mine on the annoyingly random flash mode which I prefer.
I’ve heard a lot of cyclists talk about annoying motorists or having lights too bright for motorists which I find counter-productive to advancing road safety. In light of the large numbers of city/ urban/ young cyclists I’ve seen riding around in every city I’ve ridden in low light with either no lights, or lights that hang from bags with barely a glow much less a flash, pointing at the ground, I recommend that bike safety advocates need to be talking up the brightest lights available and urge their use and regular battery changes/ recharges.
As soon as I hear motorists talking about being concerned about “dazzling” cyclists with their xenon blue lights that can light up a football stadium from a mile away I’ll start to be a little more concerned about my bike lights being too bright!
It’s also interesting that Planet Bike has just announced a 1 W version of the superflash, and also PDW has had a RADBOT 500 for a while.
http://www.ecovelo.info/2011/02/03/planet-bike-superflash-turbo/
Tim, I know that having a taillight bright enough to be seen in daylight/twilight is beneficial.
Did you try the same test with the batteries swapped between the two lights? And/or multiple times to get an average?
When I have time, I’ll repeat the test. I did it twice, and I’m not sure if I used the same batteries in the same lights both times. My camera time lapse failed the first time but I do remember that the PDW did cut out after a similar amount of time.
Jim:
I ran the test again and the results were the same. This time, both lights were using Eneloop AAA’s. (See update in original post).
Thank you for doing this comparison. I use both taillights with rechargable batteries and have noticed that the superflash lasts longer, although I have never conducted a test like you did.
I like the Radbot 1000 for brightness, but I don’t like the
shutoff feature. A cyclist is not likely to notice the loss of a taillight while riding, so it becomes a safety issue. The superflash will continue working even on low voltage – it’s a dimmer light but definitely better than nothing.
You’ve started a great discussion here Jun. I was thinking more about this yesterday and would like to point out that the other strong argument for using the strongest taillights (and head lights for that matter) is their use during daylight hours. Many people mistakenly assume that lights are only necessary during the dark or very low light without realizing the risk of getting hit during any time of the day when we cyclists blend into the confusing visuals of any given streetscape.
You throw in drivers who are impaired for any number of reason (macular degeneration, alcohol, drugs, distractions while driving) and the need for standing out and catching the attention of drivers is even greater. For example, I was nearly hit by an elderly driver during daylight hours simply because I was in a shady area on the road and I believe he had just been in a sunny area and probably had eyes that weren’t readjusting to the light change fast enough. And I was wearing bright clothes, just not using a bright taillight.
So, ever since then I personally run my lights, front and rear on strobe, day and night, and also run 2 taillights to have a backup in the event one of them happens to burn out on my ride home.