Are LEDs making dynamos unnecessary?

For discussions about bikes and equipment.
pliptrot
Posts: 553
Joined: 12 Jan 2007, 2:50am

Are LEDs making dynamos unnecessary?

Postby pliptrot » 12 May 2012, 8:02am

Lighting - thank God those Ever (un)Ready bricks are a thing of the past. I have been thinking about a dynamo, but with the state of LED lights these days I wonder if such things are entirely unnecessary?
Any experience and advice will be welcomed.

User avatar
[XAP]Bob
Posts: 16926
Joined: 26 Sep 2008, 4:12pm

Re: Are LEDs making dynamos unnecessary?

Postby [XAP]Bob » 12 May 2012, 8:09am

They make dynamos fantastic.

Particularly since they need some electronics to make them work (rectifier is useful) we now get standlights that work for several minutes, no burn out, good low speed light.

Additionallty there is sufficient power to charge my phone as I travel - all for the equivalent of a. 1/1500 hill (aka flat)
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

Brucey
Posts: 35897
Joined: 4 Jan 2012, 6:25pm

Re: Are LEDs making dynamos unnecessary?

Postby Brucey » 12 May 2012, 8:28am

actually for trundling around town, I don't bother with a dynamo any more (despite being a 30year plus hub dynamo user) . Small LED battery lights typically 'die' gracefully when the bateries are exhausted so they pretty much cannot fail without warning in any one short journey.

For regular road riding in unlit conditions an LED light + dynamo power source is the best solution. Much better than older lamps.

However for offroading the dynamo isn't powerful enough (and if it were would you want to pedal it?) so it is batteries again, but big ones which are (frankly) a pain to keep maintained. I have commuted using such a system and it is a worry to keep the batteries charged every day etc etc...

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

TonyR
Posts: 5390
Joined: 31 Aug 2008, 12:51pm

Re: Are LEDs making dynamos unnecessary?

Postby TonyR » 12 May 2012, 8:37am

LED lights make dynamos even better. The great thing about dynamo lights is you can leave them on the bike. Battery lights have to be removed or else people nick them and that makes them prone to being forgotten or misplaced. I use rechargeable battery lights for my road and off-road bikes because you can get really good bright ones these days but for my town bike its a fit and forget dynamo and LED front and rear lights.

Reigncloud
Posts: 127
Joined: 2 Mar 2011, 2:00pm

Re: Are LEDs making dynamos unnecessary?

Postby Reigncloud » 12 May 2012, 9:06am

Another great leap forward is the USB rechargeable led light. Makes charging a breeze and no more messing around with aaa batteries.

byegad
Posts: 3232
Joined: 3 Sep 2007, 9:44am

Re: Are LEDs making dynamos unnecessary?

Postby byegad » 12 May 2012, 9:24am

Speaking as someone who had a Sturmey hub dynamo in 1962 and rode in the 1980s with Everready lights that weighed a ton and had less power than the average candle.

I think modern lights are fantastic however powered. I use battery powered LEDs because I don't usually ride at night but do get caught in daylight by North Sea Haar at times where a bright flashing light is very useful.
"I thought of that while riding my bike." -Albert Einstein, on the Theory of Relativity

2007 ICE QNT
2008 Hase Kettwiesel AL27
2011 Catrike Trail
1951 engine

tatanab
Posts: 3776
Joined: 8 Feb 2007, 12:37pm

Re: Are LEDs making dynamos unnecessary?

Postby tatanab » 12 May 2012, 10:31am

pliptrot wrote:I have been thinking about a dynamo, but with the state of LED lights these days I wonder if such things are entirely unnecessary?

It depends entirely on your riding.
I have LED battery lights that give over 4 hours on an intensity suitable for lanes, or 2 hours on bright setting. Most of my night time riding is in the 2 to 3 hour range so these lights should suffice for me and indeed have done for a few years. However, this winter I fitted a modern hub dynamo with LED light to the machine most used after dark. So it's a dynamo now for me for regular night time riding, but battery lights will go on tour for occassional use.

Moodyman1

Re: Are LEDs making dynamos unnecessary?

Postby Moodyman1 » 12 May 2012, 10:56am

Yes - I do believe that modern LEDs are that good and the batteries last that long, that dynamos are looking less attractive.

Especially so, if you have multiple bikes where you can move the light over in seconds if you buy a spare mount/s.

robc02
Posts: 1664
Joined: 23 Apr 2009, 7:12pm
Location: Stafford

Re: Are LEDs making dynamos unnecessary?

Postby robc02 » 12 May 2012, 11:20am

I've still managed to be let down by batteries in LED lights. Some examples are:

1. It has been below zero all day so the batteries, which tested OK in a warmish shed the day before, barely make the LEDs glow!

2. Dodgy (slightly corroded) contacts. Had to disassemble the light, wiggle the batteries around to get them to work, and carry on home regularly looking behind to see if the (rear) light was still on. Reminded me of the 1970's!

3. Light looks OK when tested at home but in reality is really not that bright and gets steadily dimmer and dimmer - my journey is frequently over an hour long on unlit rural roads so this is quite a problem. I accept that this is my fault for being too miserly to change the batteries before they are fully dead, but I can't bear waste!! Oh, and I normally travel light (is that a pun?) so no saddlebag or room in pockets for spare batteries (some LED lights even need a tool to change the batteries).

Dynamos offer fit and forget lighting. A revelation in terms of reliability when used in conjunction with modern LEDs - no blown bulbs, and standlights for when stopped. I have a Schmidt on my main commuter, a Sturmey FG gear/dyno hub on my 1950s roadster (drives LEDs very nicely), and a B&M bottle dynamo on an occasional commuter/tourer. I also fitted a Shimano hub dynamo / LEDs to my daughter's college commuter for the same fit and forget reasons.

Long live dynamos!

User avatar
gentlegreen
Posts: 1359
Joined: 23 Aug 2010, 1:58pm
Location: Bristol
Contact:

Re: Are LEDs making dynamos unnecessary?

Postby gentlegreen » 12 May 2012, 11:21am

I couldn't generate enough power for my lights !

20 years ago I was using a 7A/H lead acid battery and two 21 watt car lights, these days my NiMH battery is half that capacity and my total power is also halved, but many times brighter. I suppose my "average" working set is 4 watts rear, 6 watts front - though I have three separate front lights available and two rear for the various parts of my journey.

I've seen what a 1 watt B&M front light on a friction dynamo can do and it's very impressive indeed, but for day to day riding, why should I compromise ?

My next addition will be rear indicators - well at least one on the right ...

Charging electronic devices on a long run is an interesting angle though - I'm starting to use mobiles, GPS and cameras - but in the short term I will be buying a dedicated battery for that...

If I ever did do a tour of longer than 48 hours I might have to think about fitting a dynamo...

thecycleclinic
Posts: 168
Joined: 20 Apr 2012, 8:58pm

Re: Are LEDs making dynamos unnecessary?

Postby thecycleclinic » 12 May 2012, 12:32pm

Supernova make a dynamo hub for off road use. Should be powerful enough to illuminate the trails. However it is 400g heavier than a normal front hub.

Ribblehead
Posts: 366
Joined: 21 Jul 2011, 3:08pm

Re: Are LEDs making dynamos unnecessary?

Postby Ribblehead » 12 May 2012, 2:50pm

Does anyone use those magnet/induction LED lights?

http://www.reelight.com/Default.aspx?ID=56

Not much to go wrong as the only moving part is the bicycle wheel!

snibgo
Posts: 4604
Joined: 29 Jun 2010, 4:45am

Re: Are LEDs making dynamos unnecessary?

Postby snibgo » 12 May 2012, 3:14pm

pliptrot wrote:Lighting - thank God those Ever (un)Ready bricks are a thing of the past. I have been thinking about a dynamo, but with the state of LED lights these days I wonder if such things are entirely unnecessary?
Any experience and advice will be welcomed.

Dynamos have the same benefit they always did: they don't go out because we've forgotten to change (or recharge) the batteries.

However, I'd say the advantages of a dynamo are less strong these days. In the days of Never-Ready bricks, come the first night ride of the year, I'd find the battery was flat and possibly corroded. I'd have to get to the shops (in the dark, without lights) to get a new battery or light. These days, I just recharge the batteries and I'm good to go.

If I commuted (in the dark), I'd probably get a dynamo. It would be one less thing to think about on cold winter mornings. But it's not such a "no-brainer" decision as in the past.

User avatar
Trigger
Posts: 1232
Joined: 6 Aug 2010, 11:54am
Location: Derby/Notts

Re: Are LEDs making dynamos unnecessary?

Postby Trigger » 12 May 2012, 3:49pm

I do a fair few all night rides, so a hub Dynamo is a no-brainer, especially considering the minuscule (i.e. undetectable to me) resistance. Win/Win.

User avatar
[XAP]Bob
Posts: 16926
Joined: 26 Sep 2008, 4:12pm

Re: Are LEDs making dynamos unnecessary?

Postby [XAP]Bob » 13 May 2012, 4:16pm

370 Lumen (http://supernova-lights.com/en/products/e3pro.html) available with MTB (i.e. light up the woods) or road (i.e. don't dazzle oncoming traffic) optics is pretty bright.

I use a dynamo lighting system with LEDs.

I have a hub dynamo which powers:
- Externally switched front LED
- Externally switched rectifier for my Reecharge USB cache battery
- Semi-permanently powered rear LED (power is only removed if a 3.5mm jack is plugged in under my "box of tricks" to power a rear light on a trailer)

The brightness of the front light is slightly reduced if I power the rectifier in parallel, but it's still adequate for night time rides.

But then I commute all year. I used to have a couple of front and a rear light al home made and powered by a block of 8 AA rechargeables - that was a daily charging regimen (which is kind of OK as it was actually every day) and risked battery failure every day.
Nowadays I don't have to think about lighting at all. Given that I used to charge at work it is more expensive initially - but I consider lights to be a valuable piece of safety gear.

Since I have a decent hub dynamo I can't feel the drag at all, and the system makes the lights as easy to use as they are in a car.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.