Re: [rootsradicals] South America Tour
- On 2011-05-05, at 3:35 PM, Vik Banerjee wrote:
> The reason no hub can survive dunking is that the seals required to allow that to happen would negatively impact the other 99.9999% of the time you used the hub for "normal" bike riding. It's not a matter of a manufacturer reluctance it's simply a matter of focusing on what really matters to most cyclists most of the time.I think it is possible to build a dynamo hub that would be not-too-degraded by getting dunked. Technically speaking, the hub is an alternator, not a generator (or a dynamo), and that means that it is just magnets and wire -- no brushes, no parts touching except the bearings. You would want everything coating the electronics to be water-repellent, so that corrosion is minimized.
After that, it's just the bearings. If you can repack them after the dunk (not possible on both sides of the Shimano hub, at least as far as I can tell), then you can recover. Reassembly can be a little tricky if you pull the coil (and ferrite) out of the magnets.
What did in the S12, is that there's some electronics in the butt of the device, that control some aspect of its operation, and they did not recover from getting wet.
Not knowing what is inside the SON (it could have similar electronics, and that would be consistent with its high performance) it could indeed be more vulnerable to the wet than the Shimano, which is clearly "just an alternator".
- Yep, that's been my latest and hopefully last solution: a 'mag'
flashlight with the new LED 'bulb' and a rechargable battery. It has
all metal housing, rubber gaskets, and three light settings: BRIGHT!!,
not so bright, and blink. It's supposed to last about 4 hours. The
problem is the housing that attaches it to the bike is still on the
privative side--needs a quick release. This thing really turns night
into day! It has to be as annoying for oncoming traffic as those
stinking halogen car headlights.
> While it has the same problem as some headlights with beams hitting other in the eyes, normal flashlights are cost effective waterproof (and often crashproof too) solutions. I use the twofish block to attach mine to the handlebar.
> Also very handy to have a proper flashlight at home or when travelling. Bike lights are usually not very handy due to their shape.