>But I am a little surprised in a way that after 100+ years(?) of dyno lighting there isn't a dragless hub yet. >Also, dyno lights with a lens that allows you to see into a turn when turning. >Also, lower prices for these things. >Also, why taillights aren't built into frames yet.
Dear Lungimsam, We don't have dragless ANYTHING. One of the laws of thermodynamics is that you don't get something for nothing. You can't even break even. If you're referring to lights-off conditions, a good alternator minimizes the eddy currents and stray induction that causes those losses, and the SON and SP hubs both lose less than 0.5w at 20mph. There are clutched systems to decouple the alternator entirely when turned off, but they turned out to have enough weight (and increased drag when on) to offset that tiny benefit. Power on, Claw-pole alternator designs can be very efficient (the SP and SON designs are around 60%, so under 6W cost for 3W of light at speed), but there are limits to what fits dimensionally and is pleasant to carry around on a 20lb machine with a 1/3 HP power source (an auto alternator is more efficient than even high-quality bike dynamos (the good ones are closer to 85% efficient if I recall correctly), but it has a large iron core, a whole lot more windings, etc, and it neither light nor small). 6W is a manageable workload for most of us. Note that nominal 6W output systems were available to drive multiple lights, but never really took off for push-bike use (they did gain a toehold in the ebike market). They require closer to 10W to drive the additional load, and that turns out to be a lot of power for the average cyclist relative to the additional light. Tail lights are built into properly integrated bikes. Perhaps not into yours, but two of my machines came with built-in tail lights, and I am hardly alone. We as customers have not historically demanded (nor paid for) fully-functional lighting systems for our sporting machines, and, because it requires more design work (and complicates assembly), bike builders have obliged by not really trying to integrate them except where required by law. The German shopping bike design requirements support all of us in this respect. https://www.flickr.com/photos/49353569@N00/3522736540/ https://picasaweb.google.com/lh/photo/EMNpauT1sq6SXSNJF_PMyNmblz4G8eB5pdrTwecIxBc?feat=directlink https://www.compasscycle.com/shop/components/lights/compass-taillight/# Many more if you consider fenders an integral part of the complete bike. Lower prices? Larger volume and cheaper materials (which works against efficiency in the case of the alternator, anyway, and good design/build quality below some threshold). I consider a $40 light, $120 hub, and $30 rear light pretty inexpensive for what you get, and, honestly, the Velo-Lumino switch is a masterpiece of low-volume value.The comparison cost would be a replacement light system for a motorcycle or an auto headlight. Not just the consumable bulb(s), but an alternator, light switch, wiring harness, control electronics, and a front and rear lens assembly. Even an Edelux/SON/Velo-Lumino switch, sinewave USB power supply, and Secula (all low-volume premium bits) end up costing less than than the equivalent system parts for a Toyota truck (go ahead, price the wiring harness and relays....) or my old BMW motorcycle, and those items were mass-produced on huge scales. You could add another light that you can aim to the handlebars or to your head (most of us ride with a secondary helmet-mount light offroad, for example), but even with 90W to work with (vs the 3W or so of a bike lighting system) most designers choose to leave the lights fixed. The Edelux II and current-generation Cyo has a pretty broad beam and still retains decent projection for riding at speed, and has enough side illumination for ordinary road use (unless you block part of the beam with the front wheel/fender/rack, as I did with the Boulder Bicycle Allroad--left-hand mount on the Nitto rack, so low-speed right-hand switchback turns are into a shadow. I think Citroen had driving lights that swiveled with the front wheels. Alternatively, you could wire a helmet-mount light into your dynamo with a permanent plug into the bike's wiring harness. I've considered doing that for bikepacking, but have just used battery helmet lights for that application do date. Maybe with my next project.... Best, Will William M. deRosset Fort Collins, CO On Thursday, February 11, 2016 at 4:46:31 PM UTC-7, Lungimsam wrote: > > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
