Battery versus Dynamo

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pete75
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Re: Battery versus Dynamo

Post by pete75 »

Brucey wrote:Electrenics engineers with whom I have worked have sworn blind that mechanical switches are the least reliable parts BTW. Its not been my experience, but hey...

cheers


Yep I've heard the same from electrical/electronics people about electrical v mechanical reliability. Funny that the most common reason for car breakdown is electrical.
It's true the mechanical bits associated with electric stuff are often a bit naff - maybe because they're designed by electrical rather than mechanical folk...

BTW my B&M back light came with a press switch which turns of the stand light presumably by discharging the capacitor.
'Give me my bike, a bit of sunshine - and a stop-off for a lunchtime pint - and I'm a happy man.' - Reg Baker
edocaster
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Joined: 10 Apr 2013, 10:43pm

Re: Battery versus Dynamo

Post by edocaster »

MartinC wrote:
edocaster wrote:......................Is there a way of immediately switching off/discharging a capacitor standlight........


The B&M ones have 2 bare contacts on the rear that allow you to short out and discharge the capacitor with something conductive like a coin. Don't know anything about the Pico though, sorry.


OK, I have the Pico now, and although I haven't tested it outside yet, initial gripes are that:
1) The off switch doesn't seem to switch off the standlight, all it does is stop new power going to the light. Hell, I can still see a glow after two hours...
2) It's very flickery below 8km/h. Might improve visibility in traffic, I guess.

...other than that, I'm quite happy so far. Plenty bright, and very unobtrusive.

I'm not sure what would need shorting out to immediately cut out the standlight. Also, does the polarity of the connection to the dynohub matter? I've currently got the cable with the white stripe going to the inner (right, when looking from the side with the connections) tab of a Shimano dynohub (which I think is earthed).
SA_SA_SA
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Re: Battery versus Dynamo

Post by SA_SA_SA »

pete75 wrote:
Brucey wrote:Electrenics engineers with whom I have worked have sworn blind that mechanical switches are the least reliable parts BTW. Its not been my experience, but hey...

cheers


Yep I've heard the same from electrical/electronics people about electrical v mechanical reliability. Funny that the most common reason for car breakdown is electrical.

A car engine compartment is a rather hostile place for electronics: it may get hot, vibrates, may get very cold when engine is off, damp etc etc. Then there is the electrical noise from spark leads etc.

pete75 wrote:It's true the mechanical bits associated with electric stuff are often a bit naff - maybe because they're designed by electrical rather than mechanical folk...

Or forced down to a price by bean counters....
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cycle tramp
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Re: Battery versus Dynamo

Post by cycle tramp »

The great thing is that you don't have to make that choice! i have battery and a dynamo... My dynamo system is one that i knitted together from lights and dynamos that have appear second hand on the forum, and the battery lights are a set that i've built myself... there are simply loads of plans on the internet for this sort of thing, and most of the electronics are available from electronic suppliers or can be found in other devices.

My first home built battery lamp, consisted of an old headlamp, a 7.2 volt battery from a remote control car, a switch, a fuse and holder, the battery charger and an old water bottle... the battery lived, zipped tied in the old water bottle, in the cage, and the lamp was bolted to a mount on the handlebars.. the bulb was only 6 volts, so being feed with a 7.2 current was really bright... on full charge the battery would last 2 hours... i ran the dynamo while i was cycling through towns and villages and switched the battery lamp on when i was in the country along narrow lanes... It lasted a number of months until one of the battery cables broke at the battery end..

i'm now making another set using one of those luxeon l.e.ds set into another bicycle headlamp and a few rechargeable AAA batteries... given the fact that these l.e.d.s now appear in things like household torches, all you really have to do is find a way of connecting the torch to an outside battery park, mounting both the torch and battery pack, and then focusing the torch beam so that it doesn't blind any other road users! Brilliant stuff :)
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breakwellmz
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Re: Battery versus Dynamo

Post by breakwellmz »

"Brilliant stuff"? :roll:
cycle tramp
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Re: Battery versus Dynamo

Post by cycle tramp »

breakwellmz wrote:"Brilliant stuff"? :roll:


Absolutely, dear boy! The bicycle is perhaps now the only vehicle that you can pilot, without having to allow the authorities to test to see if its road worthy, and the great thing is you can continue to fix, bodge, machine and engineer, any addition or subtraction to your bicycle to improve its design to fit your purposes (apart from the addition of motors or engines)... just the other day i cut my rear mudguard in half just under the rear stay bridge, fixed another rear stay support to the back end of the cut piece and remounted it using sprung washers, wing nuts and a couple of bolts, now i can get the whole bike in the back of my car by removing the wheels, partly undoing a few wing nuts and then pushing one half of the rear mudguard under the other half, as the mudguard stays allow the cut piece of the guard, just to swing under the other piece...

..bicycles are still simply the stuff of imgaination, more so now than cars or motorcycles, because these have become too complicated to alter without a greater degree of engineering knowledge and skill..

Ideas to improve pedal power are still out there, why not a floating recumbent trike? why not a recumbent trike with a sail or even attachment points for one of those kite buggy wings? Why not a bicycle that you can build into a tent? Why not a front wheel hub that allows you to grind you own coffee? Why not a bicycle with a wide enough down tube to safety store 5 litres of cooking meths? Why not a bicycle by which you can unbolt the rear triangle and bolt into place a two rear wheels and an axle? Why not a bicycle that you can turn into a street sweeper or a grass cutter...
Last edited by cycle tramp on 13 Oct 2013, 7:54pm, edited 1 time in total.
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breakwellmz
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Re: Battery versus Dynamo

Post by breakwellmz »

I almost fully agree.My :roll: was for your(Possibly)intentional pun. :lol:
cycle tramp
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Re: Battery versus Dynamo

Post by cycle tramp »

Apologies ~ i found your last message to good not to subvert, and make the point that a happier more fulfilled life does not always revlove around the first hand purchase of yet more consumer goods... for myself and alot of other folks, alot of fun can be had in repairing, modifying equipment and components, which alot of us still have in our own sheds...
...currently i'm trying to turn a drain pipe and a broken umbrella into a remote control model sand yatch :)
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rjb
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Re: Battery versus Dynamo

Post by rjb »

cycle tramp wrote:Apologies ~ i found your last message to good not to subvert, and make the point that a happier more fulfilled life does not always revlove around the first hand purchase of yet more consumer goods... for myself and alot of other folks, alot of fun can be had in repairing, modifying equipment and components, which alot of us still have in our own sheds...
...currently i'm trying to turn a drain pipe and a broken umbrella into a remote control model sand yatch :)


+1, here's a wind turbine I made in my man cave recently from recycled hubs, gutter and a stepper motor from a scrap printer, latest mod involves using a drain pipe for a 3 blade prop :!:

wind turbine
wind turbine
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840 :D
coast 2 coast
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Re: Battery versus Dynamo

Post by coast 2 coast »

Anyone know how to service bearings in their SonDelux hub?

No, I thought not.

Why would you want to bolt something onto your bike, that you can't fix when it goes wrong? You can't fix it, your local bike shop can't fix it, the place where you bought it from can't fix it, the wholesalers they bought it from can't fix it. Why would you want something on your bike that you can't service?
robc02
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Re: Battery versus Dynamo

Post by robc02 »

coast 2 coast wrote:Anyone know how to service bearings in their SonDelux hub?

No, I thought not.

Why would you want to bolt something onto your bike, that you can't fix when it goes wrong? You can't fix it, your local bike shop can't fix it, the place where you bought it from can't fix it, the wholesalers they bought it from can't fix it. Why would you want something on your bike that you can't service?



I thought about this when I bought my Son hub some eight years or so ago. I took a chance on the basis that they had an enviable reputation for longevity and that I had rarely experienced problems with water ingress in front hubs of any kind. Happily, I have been proved right so far. the hub is on my bike all winter and gets used in all weathers on some very dirty lanes. After suffering repeated failures with a number of rechargeable battery systems it was a revelation in reliability!
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[XAP]Bob
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Re: Battery versus Dynamo

Post by [XAP]Bob »

coast 2 coast wrote:Anyone know how to service bearings in their SonDelux hub?

No, I thought not.

Why would you want to bolt something onto your bike, that you can't fix when it goes wrong? You can't fix it, your local bike shop can't fix it, the place where you bought it from can't fix it, the wholesalers they bought it from can't fix it. Why would you want something on your bike that you can't service?


Same reason as I'd get anything else - it offers a feature I'd like.

There are already a myriad of things I can't fix on my bike - why would I single that one out?
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.
cycle tramp
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Re: Battery versus Dynamo

Post by cycle tramp »

coast 2 coast wrote:Why would you want to bolt something onto your bike, that you can't fix when it goes wrong? You can't fix it, your local bike shop can't fix it, the place where you bought it from can't fix it, the wholesalers they bought it from can't fix it. Why would you want something on your bike that you can't service?


There are better examples ~ take my NuVinci hub, apparantly there's nothing in that hub but a load of transmission fluid, some steel balls and a couple of plates. Apart from calling the environment agency, i have no idea what to do, should it spring a leak... perhaps get a shimano alfine 8?... but until it happens (if it happens?) i'll continue to enjoy riding it. And i guess that's the crux of the matter, all of us have accepted the risk that by using more complicated parts to improve the quality of our jounrney, then we have done so at the expense of using equipment that may not be easily fixed, should it fail...i'm not arguing for bad designs, or for parts that are designed to wear quickly to increase sales or the stock holder's dividends... but out of the understanding that the more you ask a product to do; be a hub; to be that thing that the spokes are laced into, that the bearings are pressed into, to generate electricity, hold a disc brake, be weather proof, and to do this with as little mechanical resistance as possible, then the more complicated and harder to fix that product is more likely to be..
...however if you really want a bike that's unlikely to break down, but if it does could be fixed by anyone even in the most out of the way places, then somewhere i've got an old rod braked, single speed phillips... lovely...
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coast 2 coast
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Re: Battery versus Dynamo

Post by coast 2 coast »

Dynamo hubs add extra weight and extra rolling resistance, two concepts generally considered to be undesirable on a bike. They also add extra complexity and extra expense, two concepts that I’m averse to on my bikes but some people don’t seem to mind. I want a bike that I can service. I want to be able to look at something when it goes wrong, see what the problem is, understand it and know how to fix it. Dyno hubs are difficult to service. Despite the fact that they comprise of little in addition to a normal hub, other than a copper coil, two terminals and a bunch of magnets. Son hubs have to be picked out of their wheels and sent back to Germany, (more time and expense). Even worse if you thought an SP or Revo Exposure hub was a bargain, when you compared it's price to a Son hub. When they fail, you throw them away. Dyno light systems are not easily switched from bike to bike. They do not make handy torches in the way that a normal bike light does and you generally have to carry a second torch to fix your punctures, when you’re not generating light. Dyno lights do not produce as much light as many rechargable systems and do not give you the flashing option, so handy and visable when cycling in urban traffic.

On the plus side, you don’t have think to charge or change batteries.
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[XAP]Bob
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Re: Battery versus Dynamo

Post by [XAP]Bob »

Extra drag? Do you notice a 1:1500 slope? Do you check your tyre pressure every coffee stop?
Extra weight? Do your batteries weigh nothing? Do you always measure out how much water you'll need on a ride? Do you ride silk tubs?

Sure on the TdF those might be marginl gains worth having, on the road a self sufficient bike is far more valuable.

Yes, my dynamo was somewhat expensive, but it's value in terms of reliable and vilble light is immeasurable.
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.
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