However, in the case of taillights, the whole point of them is to smear light all over the place. I run a 3 watt main light and two 2 watt secondary lights. I don't always run all three lights so I figured 5 watts is a good number. I actually probably would only run the 3 watt on the dynamo since the whole point of having multiple lights is that so you can have an entire system fail and still have a light. For the same reason, even if I had a dynamo front light I'd still have to carry at least a hand torch and a lockblock. I've been stuck 4 miles from anywhere in the middle of a snowy, potholed gravel road in the middle of the woods at 4 in the morning before with a dead light, and it's NOT FUN. In that case I had no backup and wound up slowly making my way home by holding my taillight on steady mode in my hand. Also not fun.
As far as new lights being efficient, I suppose the Philips Saferide counts as a new, efficient light. It comes with 2300 mah batteries rated at 2 hours on high. That's 1.15 amps draw at 4.8 volts nominal, which is 5.5 watts power draw. A touch more than the 5 watts I mentioned above (where I was, admittedly, just pulling numbers out of a place).
In any case, if I continued to use a battery powered 2nd taillight, that's 8 watts of draw.
I did think of something else last night on my way home. A lot of the time in the winter (the only time I really need a light), I'm plowing through poorly plowed, rutted mush. I was doing so last night. When the conditions are like this, I'm only going about 7 to 9 MPH at best, sometimes 4 MPH, steering like mad and skidding the front wheel all over to muddle through the criss-crossing car wheel ruts, for 20 minutes at a time. And that's the time when I need the most light, because it's almost impossible to see the potholes through the rutty snow even with a bright light. Also the tail is doubly important on a road where even the cars are mooshing around all over, around bends and hills in the black with full tree cover.
Is a dynamo going to be able to deliver the power at 6 MPH to keep a 1000 lumen light and a 3 watt taillight going indefinitely? 20 minutes is too long to expect a standlight capacitor to hold.
I'm also of the opinion that standlights on dynamo lights dim too much and then are easily lost among the background lights of the city, my primary habitat. The last thing I want is to start from a light, having someone turn left in front of me because the standlight disappeared among the background lights and they forgot I was there.
I have a similar situation on my commute--picking my way through rutted streets and trying to assess, "will the hardpack give way and sideslip or not?" and "will the sides of that rut let me move over to the next one?"
I've found the Luxos-U running in its higher power 90 lux mode is sufficient in those conditions right up until low-speed flicker sets in at around 5 mph. Also a reason I run an auxiliary battery light.
There is no perfect system at this stage of the game--either battery or dynamo. The best you can hope for is to put together a compromise.
Bubble is not in Germany so their lighting minimum standards are Moot ..
Eyc on my Brompton is fine.... I dont need to blind others, or descend at 50mph..
I'm getting one of those 12V 6W bottle dynamos, and putting together my own lights from a Costco 5W Cree LED flashlight ($20 for 3) and some custom electronics. The flashlight head goes into an old Royce-Union headlamp with a small rechargeable battery pack, for that vintage look. It will have a USB port, too, for powering i-phones and suchlike.
I put dyno lights on one of my bikes last year, and I don't think I'm going back to battery lights except on my racing bike. I'm in the process of putting dyno lights on my other bikes. I like them much more than I thought I would, and I knew I would like them. I cannot perceive the extra drag at all. Maybe others can, but I challenge them to measure that carefully. The convenience of knowing they are going to work is fantastic. I can still mount a battery light if I'm concerned about a failure, but I've stopped doing that. The lights have proved very reliable. I get compliments on the beams they put out, too, which is pretty impressive for a 3W system.
The drag is so low (to me) that I run my lights in the daytime as well as the night. It might make me safer, and it might not, but it doesn't hurt to run them, as far as I can tell.
The drag from a sidewall generator is quite perceptible, so I only run one of those when I really need my lights.
$50 chinese light washes the Eyc out completely on LOW mode. I've ridden with them both together.
You also tend to recommend things that are the worst bang-for-your-bucks, and what the hell is wrong with your writing style, can you compose more legibly and less cryptically.
Another pi**ing match ,< yawn> eat my shorts .. you are not paying for this.
Battery systems add a tiny bit of aerodynamic drag...you don't get something for nothin':rolleyes:...but the drag will be tiny comparably.
Getting 10W out of useful power out of a hub would be real work: 3 Crees in series at 1A -- you're definitely heading down a steep hill.
Overall, at 'typical' cruising speeds, I'm probably putting less than 10W extra into my pedals (2 Crees, Shimano hub) and getting a few hundred lumens. Definitely noticeable difference in power/speed. I could stand to have a little more light, in my opinion, so I supplement with a crappy flashlight (soon to be upgraded) and a battery-powered tail light.
And this isn't about "religion" but about data that can be measured and conclusions that can be drawn from that data.
I need a LOT more light than any practical dynamo system is going to be able to deliver. I suspect a lot more people are in my situation than want to admit it. I've had quality name brand lignts in the ~120+ actual lumens arena. I've seen people claim these lights are hellishly bright. I don't know but what I do know is the only two wrecks I've had were at night and they happened because I hit something I couldn't see. I'm not riding in Midtown Manhattan. I'm riding in semi-rural suburbia. There is just enough lighted infrastructure to make people think they can pull off a night commute with Nite Rider or Cygolite self contained lights. And maybe you will do it too for months until the night you whack something you didn't see and you fall right in front of someones SUV... crunch. You don't get to tell the DMV that you only drive in well lit city centers so you don't need to spend out for pricey DOT spec headlights. Even if you never drive at night your car better have two of whatever the manufacturer put in the front corners of your vehicle and at least bi-annually you are required to prove to an authority that they actually work. Truthfully, its not even the issue as to whether dyno lights work or not. The issue is that they cannot, in their present level of performance, serve as the sole source light source for a hardcore commuter. So why bother with them at all?
Everyone here who is anti-dynamo clearly has never ridden a good really bright modern dynamo setup. The gungho dynamo oldies here also have clearly never used any of the newer $50 dual xml lights when they tout how awesome their german regulated dynamo setups are. (german regulated dynamo setups aren't that good)
I think it would be cool to have a dynamo light system, but it just doesn't make sense in my circumstances. I have 4 different bikes that I regularly commute on. Setting up the wiring and lights on all of those bikes would be expensive and a hassle. I would have to swap my dynamo wheel among bikes or buy multiple wheels. My LED rechargeable light cost about $100 and puts out all of the light I need, and I can easily swap it between bikes. It takes minimal effort to recharge. It weighs next to nothing (100 g). My commute route is also very hilly and long, and the additional weight and effort of a dynamo system would surely slow me down.
cyccommute, I guess I'm a dynamo hub person by your definition, however I do admit that there's no newtons. I never implied otherwise.
And the amount of drag doesn't make a difference to me, but of course if you measure it, there will be a difference. I just can't feel it. Mine is a Sanyo, if that means anything in the conversation.
Anyway, you've often listed reasons you like battery lights. I understand them, and I understand they work for you. Dynamo lights are better for me. You're cool with that, right?
Putting on my moderator hat, this discussion is way too bitter for the subject at hand. Please tone it down a little.