Eyc headlight problem
On 1/4/21 1:38 am, jbeattie wrote:
On Wednesday, March 31, 2021 at 1:42:58 AM UTC-7, James wrote: On 31/3/21 3:17 pm, jbeattie wrote: Every time I read your story of SP PD8 and Luxos B giving inadequate light for night riding, I remember how well my SP PV-8 and B&M IQTec Premium lights the road beautifully in all weather and conditions, and how I scoffed at the people I rode with at night with their pitiful battery lights with round beam that didn't light the road well at all. Even worse were the people with bright lights on their helmet, who blinded everyone around them and rarely aimed at the road ahead. We definitely agree on helmet lights. On a rainy night, riding through the West Hills, the Luxos B is a be-seen light. Maybe your IQTec is more magical. Peter White's pictures may be magically illuminating. https://www.peterwhitecycles.com/headlights.php Indeed, the Luxos B doesn't appear to be anywhere near as bright as the B&M IQ Premium. -- JS |
Eyc headlight problem
On 1/4/21 4:01 am, Frank Krygowski wrote:
On 3/31/2021 12:17 AM, jbeattie wrote: People prefer brighter, battery powered lights. People "prefer" what they are told to buy, which is what's on top of the counter when they wander into a bike shop. If shops had dyno systems available and explained their advantages, more Portlanders would buy them. I think they are driven by price more than anything. Battery lights can be pretty cheap, even if the beam shape is crap and they get attached to handlebars with rubber bands. No wires. No drag, even if good hub dynamos have so little drag you don't notice. Easy to remove for a weekend fast ride or race, etc. They're more convenient - even if they go flat when you need them most. -- JS |
Eyc headlight problem
On 3/31/2021 8:21 PM, Sepp Ruf wrote:
sms wrote: Sorry to go on and on, but hopefully Frank now understands the issue better. This sort of rhetoric might have been part of why you could not win reelection in Appleville. Others have long grasped the issues about 12 volt systems: In 2001, the 12V hub, literally weighed down by incandescent lamp physics in legal requirements to provide a rather high voltage already at low speeds, would have yielded 100 (source) halogen lumens from a geometrically complicated filament. But 90 lm could already be tweaked by serially running two 6V bulbs. Today, either a 2001 or a 2021 6V hub can yield more than 300 lm (net output) from the optically preferential LED, while a cheap $20 LED dyno lamp such as the Herrmans H-Black MR4 produces 120 lm, and a beam quality unheard of even in 2011. https://fahrradbeleuchtung-info.de/helligkeitsmessung-von-fahrradlampen I think a lot of skepticism of dyno systems is due to "safety inflation." Whatever was good enough last year _must_ be dangerous this year, because there's something that claims to be "better." It applies to riding without protective headgear, sliding our feet into toe clips, removing our hands from the brake levers to shift gears, riding in daylight with no lights, riding our bikes on roads that don't have walls between cars and bikes, and much more. It amounts to retroactively imagining past dangers we were never aware of. But as with the above examples, "better" is often imaginary or completely mistaken. In particular, a harsh spot of bright light on a roadway is NOT better than a well engineered beam that gives even illumination; and blinding oncoming road users is NOT better than a properly cut off beam. A further problem should be an embarrassment to an electrical engineer. Scharf still fixates on Watts, as if they are the only measurement of quality. But the lumen per watt output of modern LEDs means 3 Watts today produces more light than systems he touted ten years ago. Even more important, advances in optic design mean a nominal 3 Watt headlight give much better practical illumination of the road than a 10 or 15 Watt system of the 1990s. Most people look at a glaring light and think "Oooh, that's bright! That's what I want!" When its hot spot blinds them so they can't see with it, they shop for something even more glaring. They don't know that there's actually something to learn. -- - Frank Krygowski |
Eyc headlight problem
James wrote:
Peter White's pictures may be magically illuminating. https://www.peterwhitecycles.com/headlights.php Indeed, the Luxos B doesn't appear to be anywhere near as bright as the B&M IQ Premium. Given the same luminous flux and strictly unintelligent camera, the darker the photo looks, the better the beam is. Except on busy and wet roads like Portland. I would never discard a dim or water-ingressed Luxos, it's usable for mods, even for low & high beam builds legal almost anywhere on this planet. |
Eyc headlight problem
On Thursday, April 1, 2021 at 1:23:44 AM UTC-7, James wrote:
On 1/4/21 4:01 am, Frank Krygowski wrote: On 3/31/2021 12:17 AM, jbeattie wrote: People prefer brighter, battery powered lights. People "prefer" what they are told to buy, which is what's on top of the counter when they wander into a bike shop. If shops had dyno systems available and explained their advantages, more Portlanders would buy them. I think they are driven by price more than anything. Battery lights can be pretty cheap, even if the beam shape is crap and they get attached to handlebars with rubber bands. No wires. No drag, even if good hub dynamos have so little drag you don't notice. Easy to remove for a weekend fast ride or race, etc. They're more convenient - even if they go flat when you need them most. Portland has plenty of shops with dyno hubs. https://www.universalcycles.com/comp...er%20Precision https://www.joe-bike.com/product-lis...s-lights-1263/ https://www.westernbikeworks.com/pro...namo-front-hub Just a smattering. I got my SP PD-8 on sale at Western for $98 or something like that. I got my light at Clever https://www.clevercycles.com/accesso...240&max=%24350 They also have dyno hubs. Plenty of supply, just not much demand. Before the plague -- and daylight savings time -- there were reliably one or two other dyno equipped bikes in the racks out of maybe 40 bikes or more. Most people who commute don't spend that much time riding in the dark and aren't willing to make the effort to get a dyno, although that demographic would be best served since most riding is in facilities and on streets. For a good set-up, its not cheap -- particularly for those who don't build their own wheels. You can get a sale table L&M for $49 and any number of blazing Chi-lights for sub $100. -- Jay Beattie. |
Eyc headlight problem
Am 01.04.2021 um 18:03 schrieb jbeattie:
Most people who commute don't spend that much time riding in the dark and aren't willing to make the effort to get a dyno, although that demographic would be best served since most riding is in facilities and on streets. Yes, you southerners (the 49th latitude is some 50 miles south of here) don't have winters where the sun goes down before the kids come home from school. Round here, in southern Germany, there are three months where you might be able to chose whether you prefer a dark morning commute or a dark evening commute (and take 2 weeks of vacation after christmas if you wish to see the sun at all). |
Eyc headlight problem
On 3/31/2021 6:49 PM, Ralph Barone wrote:
sms wrote: snip I don't know whatever happened to the plans for 12V hub dynamos. There are 12V bottle dynamos, but for whatever reason 12V hub dynamos never were marketed http://www.velovision.com/ftp-admin/VVArchive/www.velovisionmag.co.uk/showStory37a0.html?storynum=56. Come on now, Steven, dust off your EE textbooks. A typical hub dynamo transmits 3 Watts of power over a distance of maybe 3 feet. If you wanted to double, triple or even transmit 10 times as much power, you don’t need to change the voltage, just change the internal design of the dynamo. The obvious solution would be a 3 phase AC generator, with a rectifier/buck converter inside that puts out a constant 6 V with a much higher current limit. Now, inside the dynamo, there may be arguments to be made for a higher internal voltage before the regulator, but a 6V output should be good up to the point where nobody would buy one because it would sap too much energy from the rider. A hybrid design would be ideal. Regenerative braking on downhill to charge the battery but running on the battery alone when going uphill. With speed sensors, level sensors, and torque sensors, a hybrid bicycle light might rarely require recharging from the mains, especially because during daytime riding the battery drain would be limited to the small amount of power used by a DRL. |
Eyc headlight problem
On 3/31/2021 7:01 PM, Ralph Barone wrote:
sms wrote: On 3/31/2021 5:21 PM, Sepp Ruf wrote: sms wrote: Sorry to go on and on, but hopefully Frank now understands the issue better. This sort of rhetoric might have been part of why you could not win reelection in Appleville. Could be, but I think the real reason was that a developer spent about $100,000 on the campaigns of two opponents. But I will try again next year, it's no big deal either way, it's essentially a volunteer position. My big accomplishments, bicycle-related, were pushing through a bicycle boulevard, protected bicycle lanes, and a new multi-use trail (under construction). The protected bicycle lanes have been wonderful. It wasn't that the unprotected bicycle lanes were dangerous, it was that they were constantly being blocked by errant vehicles and there was no way that the police could keep up with ticketing or towing. They aren't heavily used right now because the schools have not brought back students for in-person classes, but once that happens they will be used a lot https://goo.gl/maps/a8X5mehdKCrDi1BQ6. Others have long grasped the issues about 12 volt systems: In 2001, the 12V hub, literally weighed down by incandescent lamp physics in legal requirements to provide a rather high voltage already at low speeds, would have yielded 100 (source) halogen lumens from a geometrically complicated filament. But 90 lm could already be tweaked by serially running two 6V bulbs. Today, either a 2001 or a 2021 6V hub can yield more than 300 lm (net output) from the optically preferential LED, while a cheap $20 LED dyno lamp such as the Herrmans H-Black MR4 produces 120 lm, and a beam quality unheard of even in 2011. https://fahrradbeleuchtung-info.de/helligkeitsmessung-von-fahrradlampen The article about the 12V SON dynamo mentions that you can get 6 watts out of an existing 3W dynamo at high speeds. So presumably you can get 12 watts out of 6V dynamo at high speeds, but more importantly you can get 6 watts at lower speeds. "The obvious significance of this is that bike lights powered by dynamos could soon become seriously bright - perhaps bright enough to woo back some of those who have been tempted onto the new generation of high-power rechargeables." http://www.velovision.com/ftp-admin/VVArchive/www.velovisionmag.co.uk/showStory37a0.html?storynum=56 Of course you also have people like me, and apparently Jay, that recognize the benefits of dynamo powered lights and the benefits of battery powered lights, and the situations where each one has the advantage. Not many people in the U.S. have even heard of Herrmans lights. I have one of these https://herrmans.eu/products/front-lights-4147/dynamo-10038/h-black-pro-dynamo/#technical-data on my Dahon folder. Only 200 lumens but a nice beam pattern. It cost €63 from Bike24 in Germany. Also got some of the BBB Fueltank XL bottle cages from them (now discontinued). It certainly appears that German regulations are impairing progress in bicycle dynamo lighting. I’d be sorely tempted to abandon all the current standards and go to a DC 4 wire system (a pair for power and a pair for comm), with a voltage that accommodates modern Li Ion batteries and modern electronics. 5 V, 3 A could be a nice place to start. A standard connector, an existing simple comm protocol and some sort of intelligent power management scheme could allow dynamo hubs, batteries, lights and accessories to all plug and play together. Including regenerative braking. I think that most people ride a sufficient distance in the daytime to keep a battery charged. |
Eyc headlight problem
On 3/31/2021 9:39 PM, Jeff Liebermann wrote:
On Wed, 31 Mar 2021 18:27:07 -0700, sms wrote: My big accomplishments, bicycle-related, were pushing through a bicycle boulevard, protected bicycle lanes, and a new multi-use trail (under construction). The protected bicycle lanes have been wonderful. It wasn't that the unprotected bicycle lanes were dangerous, it was that they were constantly being blocked by errant vehicles and there was no way that the police could keep up with ticketing or towing. Nicely done. In the People's Republic of Santa Cruz, the "pedestrian" bridge over the San Lorenzo River is routinely blocked by police, parks, state, and other vehicle using it as a short-cut when Hwy 1 traffic is at a standstill. The vehicles manage to squeeze over the bridge with about 1ft clearance on each side. That means that everyone has to walk or ride ahead or behind the vehicles as they slowly and carefully crawl across the bridge. I suspect that some oversized vehicle will eventually try to make it across and create an Ever Given style blockage. I suggest that you remember this for when the next bicycle trail is proposed and try to specify some kind of vehicle barrier or minefield to discourage non-emergency vehicles from using it as a roadway. There are a couple of issues with protected bicycle lanes that we've had to deal with. Some of the streets have houses and the garbage cans need to be placed in a way that they don't block the bicycle lanes. Street sweeping is more complicated; eventually there will be specialized sweepers that can handle this, but for now the protected bicycle lanes are swept manually into the street then the street sweeper picks up the debris. Some residents that live on the streets with protected bicycle lanes were unhappy about losing street parking, but even before the protected bicycle lanes were put in very few residents parked on the street. My personal feeling is that public roads should be used for public access which takes precedence over them being used as parking areas, but I understand why they were upset since if they have guests with vehicles those vehicles would have to park on adjoining streets. |
Eyc headlight problem
On 4/1/2021 1:23 AM, James wrote:
On 1/4/21 4:01 am, Frank Krygowski wrote: On 3/31/2021 12:17 AM, jbeattie wrote: People prefer brighter, battery powered lights. People "prefer" what they are told to buy, which is what's on top of the counter when they wander into a bike shop. If shops had dyno systems available and explained their advantages, more Portlanders would buy them. I think they are driven by price more than anything.Â* Battery lights can be pretty cheap, even if the beam shape is crap and they get attached to handlebars with rubber bands.Â* No wires.Â* No drag, even if good hub dynamos have so little drag you don't notice.Â* Easy to remove for a weekend fast ride or race, etc.Â* They're more convenient - even if they go flat when you need them most. The mount and the beam shape should definitely be taken into account when buying battery powered lights. A good battery powered light doesn't cost $5, but when you get into the $40-$60 range there are some excellent choices. Personally I'd like to see aluminum or steel mounting brackets but those aren't that common (Lezyne had some available but they didn't ship with the light). As to the beam shape, it's important to remember why dynamo lights have the beam shape they do. The limited output needs to be precisely directed on the road. But some spill off to the sides, and upwards, is actually desirable. Unless you're in Ohio where panel delivery trucks routinely knock down low-hanging branches, having some amount of light shining up is extremely useful. Especially nice are some of the lights where you can use a replaceable 18650, 25650 Li-Ion battery or 3 AA batteries. I have one of these on my mountain bike and I fabricated an extremely secure metal mount for it and it sits under the handlebars. The 26650 battery cost more than the light https://www.orbtronic.com/26650-battery-protected-li-ion but I could have used a much less expensive, lower capacity, 18650 battery (or three NiMH AA cells or three non-rechargeable AA cells). |
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