Cycling UK Forum

I don't think the crc one linked to will work, as the 'stud' seems too far up. I think it was made for the horizontal kidney bean light.

But you can get Smart brackets that do work easily. Failing that, the Portland Design Works ones are identical. All have 4mm screws. Don't get Smart clones (e.g. Oxford brand) with a 5mm screw, as the stud is in slightly the wrong place.

I used the provided clamp. There wasn't really any space to push the wire strands as far as the holes in the spades, thread some through and fold them back, but the friction of the clamp itself seems to be doing a decent job.

For the light itself, it's a little hard to judge so far (as I don't see it fully 'on' while riding the bike). Standlight seems a little dim and shortlived compared to my headlamp though.

[XAP]Bob wrote:
"load" is provided by a rear dynamo light, it doesn't need to be alot.

Does the load have to be 'upstream' of the regulator? Or can I just permanently solder a light (LED and resistor) parallel to the USB output?

Further update: After a total of 17 km (10 with lights off, 7 with lights on), the same phone (this time switched off) has now gone up to 9 bars. I'm happy with that - pretty much as per spec.

However, the phone exhibited some strange charging behaviour, based on what I could see of the charging light. It would light up pretty much at walking pace, but if I accelerated too quickly to beyond 20 km/h the light would disappear. However, if I accelerated slowly, the charging light would remain lit at most speeds (I clocked 40 km/h).

I have no practical way of measuring voltage at the dynamo or USB output while riding (I only tested at 'handspun' speeds before finishing the unit, and it always hit 4.9-5.0v exactly). A total guess would be that output voltage is fine, but somehow the phone doesn't like a sudden increase in available current.

I'm a little worried that when the charging light goes out that leaves the charger in a no-load situation. Is it likely to be OK (I'm unlikely to do more than 50 km/h on this bike)? Or, even though I'm loathe to redo part of the circuit, is there something smart I can add (I might just about have enough room for something parallel across the input (I've heard about something called zener clamps?) or output (a small permanent load?))?

Thanks.

mjr wrote:I'm not finding good second hand hub dynamo wheels with lights within the £50ish budget here, ebay or Gumtree. Where are you?

Even the £70 wheels I've seen contain hub dynamos that are slated by people on this forum and I'd like to give dynamos a fair crack. Resale is time consuming too.

I'd probably use a cheaper known-brand dynamo than the €15ish Axa HR and use the money saved on a more reviewed headlight but the extra delivery charge of ordering from two shops would wipe out any saving.

This is actually about as high-end as you can go, I believe: http://www.ebay.co.uk/itm/171149364552 - will probably go for a much higher bid than it is at now, but if you keep a lookout you can probably get a decent wheel for less than half of what this one goes for.

OK, quick update. I built the charger - pics below show the board, and the final unit in a vitamin tube (which has far more room than is necessary).

Total cost in parts probably less than £15, not including soldering iron and time!

The part permanently attached to the bike is a pair of wires (recycled from an old phone charger) parallel to the headlamp wires going to the hub (hint: twisting two pairs of wires and shoving them into the Shimano 'lego brick' connector is really difficult - must remember to pick thinner wire next time...), terminating in a Tamiya connector zip-tied to the stem. The charger can be detached when not needed, or when it risks being overloaded.

Only had a brief test today, using an old smartphone (HTC Hero) as test dummy. Started out at 7/10 bars of charge. After 2km... 7/10 bars However, that's no surprise, as the site I followed estimated 1-2% per km, plus as the phone was on, the screen would switch on every time it started or stopped charging (which, incidentally, began at around 8km/h). I'll do a longer test, perhaps with the phone off, soon.

So far, pretty satisfied. If it works as planned, I'll seal the unit and add some more heatshrink.

malverncyclist wrote:Ok, all fitted, lights connected and lights work . But, at higher speeds there is a 'whirring' noise coming from the hub, is that normal?

Martin

I get some buzz through the handlebars on my Shimano dynohub. I guess resonance can make the forks 'sing'.

mjr wrote:[*] http://www.bike-discount.de/shop/k342/lights.html - Axa HR + Axa Pico 30 T Steady Auto LED headlight + Axa Ray Steady LED which I think works out about £45 after delivery and conversion.[/list]

Are there others that you would suggest?

As a recent dynamo convert, and a user of the Pico, I'd say it's bright enough. Could be brighter, but I guess I'm spoiled by Cree battery LEDs. Feature-wise, there are a few gotchas though - as far as I can tell, no version has a switch which can disable the standlight, and all switched versions have no more than two positions (as an aside - why do dynamo headlights come in so many different versions? Surely this is hugely inefficient in terms of economies of scale, and leads to much surplus stock? I'm sure every version of the Pico cost no more than about £9 to produce...). But I'm quite happy that it gives all the main benefits of modern dynamo lighting, for relatively little money.

If you're already willing to pay up to £20 for a bottle dynamo, an alternative would be to look out for dynamo wheels on eBay for a little more. As long as they're not shot bearing or electrical-wise, you may find a bargain.

Thanks for all the advice (in spades!)

I'll try the bare wire approach first, and if it's not satisfactory I'll get some spade connectors from eBay. Either way, I think I'll avoid too much weight hanging from that connection.

Hello all,

I recently took delivery of a B&M Toplight Flat S Plus dynamo tail light, and have just ordered a cable to connect to the front light (annoyingly didn't know it wouldn't be included with either my front or rear light).

Both the 'pigtails' from the front light (Axa Pico 30) and the Flat S Plus have the same male spade connectors, but I think the cable I've ordered only has the female spade connectors at one end. However, the Flat S Plus does have a mystery T-shaped piece of plastic. I'm hoping it is used to clamp bare wires to the light - certainly the last two posts from http://www.bikeforums.net/archive/index ... 04544.html indicate that may be a possibility. It's just a shame there are no real instructions on this.

Does anyone know which way to clamp the wires? Picture attached below. I'm thinking the wire can come in from the bottom, although only a few strands would get caught against the spade? Or perhaps through the hole in the spade, and then around the spade, so it gets held by friction?

Thanks.

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).

RJC wrote:It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.

I think this - https://plus.google.com/u/0/photos/1128 ... 7953872609 - referred to from this German forum - http://www.radreise-forum.de/topics/976402#Post976402 - shows just that. I believe the third picture is the Pico, and the fifth the Union (fourth appears to be both combined).

james01 wrote:

RJC wrote: It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.

.

I've been using a Pico for a while, astonishing value http://www.rosebikes.co.uk/article/axa- ... aid:642367 .

I'm thinking of getting a Pico. But the version I want (steady switch) is out of stock. All the other versions don't seem to have an off switch.

Is there a way of immediately switching off/discharging a capacitor standlight, so it doesn't remain lit after parking up/getting to a train station platform/etc?

I thought I should give an update on this.

Finally finished shortening all the spokes that needed it. A long task, as I couldn't use needed outdoor space for the rotary tool on rainy days, so had to resort to hacksaw and combination pliers, plus copious filing smooth afterwards. I was tempted to just buy shorter spokes when I had about 8 left to do, but I think the rebuild would have been just as difficult.

I was fastidious about getting the tension back to what it was before, right down to recording the plucked tone of each spoke before shortening. But this was largely unnecessary, as the wheel wasn't true anyway. Spent a good amount of time today true-ing it and putting in the required dish (the hub is disc-specific).

Now looks fine. Just need to put on the Schwalbe rim tape and all is ready (well, except lights...).

Gearoidmuar wrote:

Brucey wrote:
BTW in the short term there is a dodge which may get you going again; if you make a mark on the cones where the pitting is, and transfer that mark to the locknuts so you can see it when the wheel is in the frame, you can put the wheel in so that the worn parts of the cones are uppermost (and forwards facing in the case of a rear wheel). This means they won't see any real wear loading in service. You can go a long way like this with no further trouble, provided the pitting isn't too bad, and you have 'au point' bearing adjustment.

hth

cheers

Clever clever Brucey!

For a dynohub front wheel, would I be right in thinking the cable exit point always corresponds with the same part of the cone? As they're generally fitted in the same orientation all the time, does that mean these hubs are automatically more prone to cone wear in the same spot?