Lights - Dynamo vs Battery

[zigzag]

i'll be using smart 60 lux light, 2aa batteries enough for the night in high mode, brighter beam than b&m luxos (not as wide though). i like the luxos light in "boost" mode if it was always on, it would make me seriously consider the dynamo option.

[Frank9755]

Anyone got any comments on the Exposure Flare rear light for PBP

It would be anti-social behaviour: you don't need a bright light like that!

[fussballclub]

^^ Yep even thinking that back to the start. Please don't.

[jamesld8]

Anyone got any comments on the Exposure Flare rear light for PBP

It would be anti-social behaviour: you don't need a bright light like that!

don`t know how bright Flare is but if it`s anything like a couple of bright tail lights I`ve encountered please avoid---can be blinding (although it could be a good deterrent to wheelsuckers Maybe there`s a need for such in city traffic situations but otherwise don`t think so

Re dynamos though---convenience factor is high; and weight also ? the Shimano dynohub adds about 350gm to bike weight; by comparison for the battery lights I would use---1000 lumen Cree---I`d be taking at least 1 x 6600mAh and 1 x 4400mAh battery packs which weigh in at 600gm + Maybe my lighting could be too bright but it`s what I feel I require to avoid UK road hazards ie potholes

[citoyen]

They do need to be pointed down a bit, but it's also a design fault, I'd say... Insufficient or bad beam shaping.

True. Probably because most of the really powerful bike lights are designed more for singletrack riders, where you actually want a good all round spread of light to avoid overhead obstacles such as low-hanging branches - in fact, the Cateye Volt 1200 explicitly says in the instructions "not for road use".

One of the best high-powered lights for road use in this respect is the Lezyne Mega Drive. It's damn heavy but it has a better shaped beam than most - the slight peak over the top probably helps a bit.

I've been using the Gemini Duo, which claims to produce 1500 lumens - massive overkill for road use but it has three user-definable settings and most of the time on the WCW I was riding with it on the lowest setting (10%, I think). I boosted it to medium or high for some of the lanes, when the extra light was useful for avoiding potholes - and when there was no oncoming traffic to annoy. It has no beam shaping though, so potentially very annoying for riders coming the other way, but I tried to have it pointing right down at the road in front of my bike so I hope that did the trick. It also has a bit of lateral adjustability, so I try to point it slightly towards the nearside of the road (another useful feature of car headlights - which is of course why you need to put the stickers on them when driving abroad).

[Veloman]

Anyone got any comments on the Exposure Flare rear light for PBP

It would be anti-social behaviour: you don't need a bright light like that!

^^ Yep even thinking that back to the start. Please don't.

^^^^ Agree with the above and very grateful flashing LEDs are banned in France and on PBP. (Oh wait, spot the UK rider with flashing LEDs!)

These will last a long time and can be distributed over the bike and worn on helmets:

http://www.7dayshop.com/products/7dayshop-bike-light-super-bright-led-bicycle-lights-front-rear-7DAY-S-CA-1024

[Aunt Maud]

Can't stand those flashing rear LED's.

Please stop using the bloody things.

[simonp]

They do need to be pointed down a bit, but it's also a design fault, I'd say. The trouble is there is often too much beam above the bright spot. You want that bright spot pointed fairly high up so as to illuminate the road a decent distance ahead of you and avoid making everything else look dark in contrast, but that leaves too much of the beam going up into oncomers' eyes. Insufficient or bad beam shaping. As well as not pointing the things down a bit.

The trouble this is that the person riding with the light is not the person experiencing the light face-on. However, the Edelux II, Edelux, and all the IQ lights meet
 the German lighting regulations and this specifically includes how much light is above the bright spot. As for any dipped beam light, including a car headlight, if it's incorrectly set-up, the light will dazzle oncoming road users.

I have ridden with a lot of people who have these lights with sharp cut-off, but they clearly have aimed the light so that the cut-off is above the horizontal.

[Veloman]

Can't stand those flashing rear LED's.

Please stop using the bloody things.

Agreed.

Fortunately these have non-flashing mode too:

http://www.7dayshop.com/products/7dayshop-bike-light-super-bright-led-bicycle-lights-front-rear-7DAY-S-CA-1024[/quote]

[Aunt Maud]

They do need to be pointed down a bit, but it's also a design fault, I'd say... Insufficient or bad beam shaping.

True. Probably because most of the really powerful bike lights are designed more for singletrack riders, where you actually want a good all round spread of light to avoid overhead obstacles such as low-hanging branches - in fact, the Cateye Volt 1200 explicitly says in the instructions "not for road use".

One of the best high-powered lights for road use in this respect is the Lezyne Mega Drive. It's damn heavy but it has a better shaped beam than most - the slight peak over the top probably helps a bit.

I have a pair of Lezyne Deca Drive front lights. Usually one on low beam (250lm/6hrs burn time) is enough, but I take pleasure in doing the double up on high beam as a special treat to either Motons who refuse to do the dip lights thing or cycle fucktards who use those daft circular MTB spots or cheap Ebay Cree spots on the road.

A retina searing blast of 1800 lumens usually produces a satisfactory result. 

As they're on my bars I can place my hand over the top of the lens to create a dip beam effect for other oncoming road users and I'll only use high beam on both when I'm alone on an unlit fast decent at night, with no other traffic on the road.

I've got a pair of 7 lumen rear lights, usually one is enough.

http://www.lezyne.com/product-led-sport-femtorear.php#.VXfUkV49LZs

[citoyen]

For the rear, I've been trialling a Bontrager Flare R - it's designed for daytime visibility and has a pretty obnoxious flashing setting for that purpose, with 65 lumen bursts. On the low, non-flashing setting, it's plenty bright enough for night time use and still had lots of juice left after being on all night - hard to quantify but maybe as much as 50%. If I were doing PBP, I'd take a couple of those and have one charging while the other is in use.

There's also a version with a remote ANT+ switch to mount on your handlebars. IWOOT.

[Cudzoziemiec]

They do need to be pointed down a bit, but it's also a design fault, I'd say. The trouble is there is often too much beam above the bright spot. You want that bright spot pointed fairly high up so as to illuminate the road a decent distance ahead of you and avoid making everything else look dark in contrast, but that leaves too much of the beam going up into oncomers' eyes. Insufficient or bad beam shaping. As well as not pointing the things down a bit.

The trouble this is that the person riding with the light is not the person experiencing the light face-on. However, the Edelux II, Edelux, and all the IQ lights meet
 the German lighting regulations and this specifically includes how much light is above the bright spot. As for any dipped beam light, including a car headlight, if it's incorrectly set-up, the light will dazzle oncoming road users.

I have ridden with a lot of people who have these lights with sharp cut-off, but they clearly have aimed the light so that the cut-off is above the horizontal.

That's another problem as well. The regulations tend to favour dazzle-restriction over illumination, but the people using the lights tend to prefer the opposite. Not restricted to bike lights, either. It's conceivable that a more gentle cut-off would result in less dazzle in practice. And then there's the variation in sensitivity of our eyes.

Anyway, a bit OT cos clearly these problems are found in both battery and dynamo lights.

[Exit Stage Left]

Fighting the lighting arms race is a lost cause. You've just got to factor in exposure to blinding lights, and decide whether it's worth putting up with or not.

[citoyen]

These will last a long time and can be distributed over the bike and worn on helmets:

Fortunately these have non-flashing mode too:

Are you on a commission?

[citoyen]

I have a pair of Lezyne Deca Drive front lights. Usually one on low beam (250lm/6hrs burn time) is enough...

A retina searing blast of 1800 lumens usually produces a satisfactory result. 

That looks like a good setup - two Decas is probably a better choice than one Mega. I presume the 1800 lumen blast thing means the Deca has the same "overdrive race" mode as the Mega that allows you to toggle between "economy" and "overdrive" settings.

Will you carry spare battery packs for PBP?

As they're on my bars I can place my hand over the top of the lens to create a dip beam effect for other oncoming road users

iirc the Lezyne light bracket also allows a good degree of offset, so you could just as easily twist the light to point more towards the side of the road.

[Aunt Maud]

It's just a push of the button to go between high and low beam, but you need to set it up when you first get the lights with I think its a five second press of the on button, although I can't quite remember exactly. The lights are pointed down a tad, so they don't shine into other peoples eyes too much. They've saved me from hitting Badgers and an Elk, so I'm happy using them despite the extra bit of weight.

I changed the thumb screw on the bracket to an allen head screw and as the lights are mounted either side of the stem with the Garmin in-between I can't really move them to one side. I do the hand over the light thing as a gesture to oncoming vehicles to show that I've dipped my light and expect them to do the same. It's no big deal to do with one hand.

I'll be using both at the weekend on The Pendle, as there are some late night descents, but I might just take one on PBP with a couple of extra batteries. I've got a power bank too if I need more charge and as I'm in the 84 hr group on PBP, I'll try and do all my night riding at just before dawn, so I shouldn't need to use it too much. I certainly don't plan on riding through the night at all, but you never know.

[citoyen]

It's just a push of the button to go between high and low beam, but you need to set it up when you first get the lights with I think its a five second press of the on button, although I can't quite remember exactly.

Yep, that's what they call the "overdrive race" mode. It's a useful feature. Otherwise pressing the button cycles between all the different settings.

[LEE]

I decided to ruin the looks of my Trek Domane and fit a Dynamo touring wheel for PBP.

The convenience of Dynamo lighting outweighing the performance benefits of a non-dynohub wheel for me.

So I did a comparison during the wheel swap.

Bontrager Bladed Spoke wheel - 25mm Conti 4 seasons tyre + B&M IXON battery light + 3 sets of AA batteries(12 in total)

Now

Rigida Chrina, same tyre + Shimano Dynohub + B&M CYO light

The difference is 188grams or 6 ounces heavier.

I can certainly live with that because that's not much more than another set of AAs.

I assume most of the additional weight is at the hub.  Add to that a bit of drag from the dyno through the night of course and it will slow me down.

The question is whether it will slow me down more than stopping to change batteries or/and shop for extra batteries.  i don't really care, it's one less admin task to take care of.

My Mantra is currently "Comfort and Convenience".

[zigzag]

in my case swapping out two aa batteries takes less than 30s; i'll need to do that once or twice. hardly an inconveniece, plus other benefits of seperate lighting and rolling systems.

[simonp]

Such as when your front wheel needs to be replaced.

[Veloman]

Such as when your front wheel needs to be replaced.

Might we assume that unless the 'team car' is following you with a spare for a TdF style quick change, then a wheel would be procured from somewhere that could also supply a light using batteries?

[Frank9755]

I agree that the impact of the weight is not likely to be significant, but the power loss with a hub dynamo is far from negligible. 

If it's 5W, given that many riders will ride PBP - at least on the way back - at less than 100W average power, they would be sacrificing > 5% of their available power.  Given a cube relationship, speed will still be >1.6% less, which at 20km/h, equates to 0.32km/h.

Multiply that up by 90 hours and it suggests it is the equivalent of riding an extra 28km.  Unless I've got the maths wrong somewhere, that's not negligible: Zigzag could change a good few batteries in the time it would take you to do that!

[LEE]

I won't have the light running for 90 hours, more like 24 hours.

Actually I'm not questioning the efficiency of battery lights, I know there's a downside to dynamos, this is a personal decision, based on what makes me feel most comfortable.

Until this year I rode every Audax with a Dynohub, including PBP 2011.

There's also plenty of time for me to have yet another total lights/Luggage strategy rethink.

[Veloman]

As a recent user of a dynamo hub (SON Deluxe) and light (Edelux II) I have not noticed a difference regards additional power requirement to maintain my average speed.  I even use it on fast club runs and do not appear to find it anymore difficult to keep-up than when I put the non-dynamo wheel in (same tyres/spokes/rims).  When asked what was the hub, I said it was a Barnes Wallis special design as it resembled a bouncing bomb; I had to point out the light!  It could be I have suddenly got fitter, as the hub undoubtedly generates some drag, but I yet to notice any tangible difference.  Far more effort required to carry kit that is not required or just refill the bidon more often rather than carry unnecessary weight.

What is nice is forgetting about batteries and having more space on the handlebars, or being able to use a small bar bag (Decathlon Velcro strap-on) without it getting in the way oof the light.  Having the light lower down is also better IMO.

[The Wheeler]

I use a battery light its more than powerful enough .
But I have it on my helmet so I can use it to read routesheet etc..
I never have it fixed on my bike ,will this be a problem with the bike checkers?