Dosun U1 with Daytime Running Lights
We at Intelligent Design Cycles have been in the process of developing high quality but affordable hub dynamo driven lights for a number of years. Our mission is to bring high quality hub dynamo driven lighting systems to the market that rival if not surpass the best in the trade, but would nevertheless be affordable enough that parents concerned about child safety would consider putting them on children’s bicycles. During the course of this exercise we have personally tested all the best German, Dutch, Finnish and other hub dynamos hub dynamo lamps we have been able to find with the intention of bringing the best aspects from each maker into our products. Two years later … we are still hard at work (the product development process is a bit more difficult than this former international trade economist imagined). But …
Since we embarked on our mission to develop our own hub dynamo lights, a number of companies have launched outstanding new hub dynamo lamps with characteristics we intend to deliver in our products. Perhaps the most sturdy and handsome arrival to date, the Dosun U1 is also our current favourite and most highly recommended dynamo headlamp. Attired in heavy duty and yet beautifully finished aluminium, the U1 produces a powerful automotive beam pattern (i.e. having a horizontal cut-off to prevent glare vis-à-vis oncoming traffic) that is comparable and arguably better than the best we have tested. Although Dosun is capable of and indeed currently produces lamps meeting the strict German StVZO regulation for bicycle headlamps, they have opted not to complete the cumbersome and expensive process of certification and pass the cost savings on to consumers. Dosun has nevertheless assured IDC that the U1 meets the StVZO standard based on in-house testing.
From our perspective, the decision to enhance the cost competitiveness of the U1 is a boon for cyclists outside of Germany - and even for those in Germany not intending to use it on public roads ;). Although the 50 lux achieved at the standard 10 meter distance places it among the most rarefied of leading dynamo headlamps worldwide, it is the U1’s 175 spec. sheet lumens rating that truly sets it apart. Perhaps more remarkable than the raw lumens output of the U1 is the user friendliness of its essentially unbroken beam pattern. This is notable because, due to the complexities of optics design, small reflectors normally produce either high lux ratings (i.e. normally highly concentrated light) with a large dark spot between the rider and the beam pattern on the road surface, or lower lux ratings (normally more diffused light) with less or essentially no dark spot. With a combination of both high lux rating and very little dark spot, Dosun’s optics engineers have succeeded in crafting a beam pattern with a high degree of uniformity projecting far ahead of the cyclist. This translates into a headlamp providing nighttime cyclists with the ability to identify obstacles from afar and track them all the way to the front wheel with a high degree of clarity. The resulting headlamp is excellent both for leisurely rides (although the beam pattern is not as reassuringly broad as the H-Diver), as well as speedy commutes even on irregular surfaces.
Aside from providing well thought out “to see” lighting, the U1 also offers extraordinary “to be seen” lighting. The system is comprised of five dedicated LEDs neatly arranged below the main reflector that make up the U1’s Daytime Running Lights (DRL). This small strip LEDs provides a number of benefits resulting partially - and paradoxically - from the advantages of the strict StVZO regulation in reducing glare towards oncoming traffic. By requiring a strict horizontal cut off above which very little light from the frontal lighting is permitted to project, the distance at which motorists can see an oncoming cyclist is reduced. The combination of low power draw and relatively diffuse light coming from the LEDs compromising the DRL allows them to be pointed at oncoming traffic making the cyclist highly visible even during the day, and more so at night, without at the same time producing such a concentration of light that oncoming traffic is subject glare, dazzling or blinding. Moreover, the DRLs by virtue of their low power consumption compared to the more powerful frontal lighting LED, prolongs the length of the standlight function (during which only the DRL is “on”) by up to 100% beyond that required under the StVZO, i.e. from 4 to 8 minutes, without decreasing but in fact increasing frontal visibility.
We have put this lamp though well over a year of testing including a cold and wet UK winter and have had problems with none. We confidently provide a 1-year warranty on this lamp.
Specifications
Compatibility: This lamp is compatible with all hub dynamos we sell and are aware of, and is an excellent match with the SunUp Eco bicycle light generator.
Standlight: Daytime Running Lights (DRL) provide a high level of frontal conspicuity during nighttime and even during the day for up to eight minutes at stoplights. Multinational road traffic safety research shows that having lights on during the day especially under rainy and even under merely overcast conditions significantly increases rider safety.
Switch: Yes, headlamp has a highly weather resistant ON/OFF switch.
Rear lamp: The light comes complete with wiring compatible with any standard dynamo rear lamp.
Overvoltage protection: In line with most modern dynamo lights we are aware of, the U1 comes with overvoltage protection insulating the LEDs from excess power at high speeds.
Mounting hardware: This headlamp comes complete with the stainless steel bracket pictured in the photo. This bracket is also suitable for mounting on cantilever bosses.
Intelligent Design Cycles is proud to be an authorised agent for Dosun products worldwide. In short, dealer inquiries are warmly invited.
