London-Edinburgh-London 2013: The thread

[Arch]

Well, ok, as you're not interested in dynamoes, and apparently not up for the LEL, goodbye!

And yeah, that Baron's fine, just some gaffer tape and splints made from chopsticks...

 

[Ashaman42]

And remember, if gaffer tape doesn't fix it that only means one thing...you haven't used enough.

 

[Arch]

And remember, if gaffer tape doesn't fix it that only means one thing...you haven't used enough.

 

[GrumpyGregry]

or you need some stainless steel zip ties under the gaffer tape

 

[Arch]

or you need some stainless steel zip ties under the gaffer tape

Jubilee clips are your other friend. And p-clips.

Hmm, I wonder how easy it would be to build a bike entirely out of bodges!

 

[Tynan]

Well, ok, as you're not interested in dynamoes, and apparently not up for the LEL, goodbye!

As it happens I'm interested in both

 

[Arch]

Ok, and I'm sorry if that was a bit brusque.

Anyway, there seems to be a big thumbs-up for hub dynamoes...

BTW, why does the spellcheck insist I've got it wrong? it wants me to say dynamos. But it ends in o, like potato and tomato....

 

[arallsopp]

BTW, why does the spellcheck insist I've got it wrong? it wants me to say dynamos. But it ends in o, like potato and tomato....

I think it came into English through the German, and is probably short for something quite a lot longer, so the standard rules don't apply. I'm sure Auntie Helen will know.

Anyway, you can avoid the whole issue by saying SONs, which is the only hub dynamo I've any experience of. Afficionados wanting demos of these gizmos, should send hellos via memos, or limos with cappuccinos. Winos and whackos need not apply, for fear of fiascos.

oh, and back to Tynan's original point, yes, there is some drag, but it is 'free power'. Sure, it takes a little effort out of your legs, but then you do make a saving on brake pads.

 

[Nuncio]

And another vote from me for dynohubs on long Audaxos ().

I'd also second the 'and winter commutes' nomination but that is less clearcut. It depends, amongst other things, on how much 'see' is required as opposed to 'be seen' on the commute. And you have to be a regular commuter to make it worthwhile financially. These would be the main considerations rather than drag (like the others, I don't notice it).

As well as a gradual improvement in the efficiency of dynohubs over several years, there has been a sharper increase in the efficiency of dyno-driven lights. I swapped from an just adequate B&M lumotech a couple of years ago to a B&M IQ Fly, which is plenty good enough but which was put in the shade (sorry) a year or so ago by the IQ Cyo.

 

[Tynan]

so is there drag or not, people have posted yes and no haven't they?
if i was flogging my guts, on my uppers on the LEL, I' not sure I'd be too interested in drag

 

[Arch]

Not nearly as much as a bottle dynamo. Minimal. Virtually unnoticable.

I think the fact that Arallsopp has done the LEL with one suggests that it's not a key problem. Hills, headwinds and having your bike held together with zipties are much more of an issue

 

[arallsopp]

Tynan, hard to say, mate.

If you *think* there's drag, there is. If you're looking for it, its there. On a tough day, everything drags. On a good day, I often find I've left the lamps on for the week and never realise.

There is drag. The SON less than others, but still measurably present. Whether its noticeable is subjective, and whether its worth it is relative. From what I could see, SONs are very common on long rides like LEL as at present there's really no cost effective alternative for what might be 40hrs of pitch black roads in counties unridden, without chargers, stars or moon.

If someone came out with a £400 battery / lamp combo that would throw the same amount of light out with a lightweight battery, no memory effect, capable of running front and rear for 48 hrs between charges without dimming, I'd still keep the SON.

 

[PalmerSperry]

There is drag. The SON less than others, but still measurably present.

Alledgedly equivalent to 1 foot of climbing per mile with the light out, and 4 feet per mile with the light on. However those figures have been floating around for a while and presumably relate to a SON28 with a halogen bulb? A SON20R with a LED lamp should be lower on both camps?

If someone came out with a £400 battery / lamp combo that would throw the same amount of light out with a lightweight battery, no memory effect, capable of running front and rear for 48 hrs between charges without dimming, I'd still keep the SON.

That would have to be a very lightweight battery, if we assume the same light emitting components then you'd got ~230grams to play with for your battery as that's the weight of the SON20R less the weight of a normal front hub. I don't think battery technology has advanced *that* much yet! And like you, I'd keep my SON thank you very much!

 

[Bollo]

The heart says yes, but the volvo'ed shoulder says no. The bum has started legal proceedings to get a restraining order on the heart, and the knees have written a threatening note from cut-out newspaper lettering and shoved it in the left ventricle. Very very tempted, but I know my limits; I'm a one-day specialist.

Arch - If you manage to get down to Winchester, PM me if you want to try some local rides. I'm like a Garmin 705 for Winchester routes, only without the personality.

 

[Ian H]

I've done LEL, PBP and longer rides with bottle dynamos. You just get on with it and ride. Last PBP was with a Schmidt hub. Much quieter, more reliable, less drag (though I suspect a lot of the 'drag' with bottle dynamos is imaginary, caused by the noise).