Every detail has been meticulously considered to accomplish such an enhancement. The premium dynamo construction offers not only a new dimension of riding comfort, but also a dynamic force inside the hub. In addition to its low resistance and ultraslim size, this new series is unbelievably light in weight and incredible efficient. With Shimano Center Lock Disc mount.
The unique aerodynamic shape of the hub has been optimized to a golf size, while attaining an unprecedented weight only 323g.
From wheel size 400mm(16") to 535mm(20"):
The 9 series output perfectly matches German StVZO 6V3W/20" regulation. As can be seen from the table, from wheel size 400mm(16") to 535mm(20"), the 9 series output is designed to meet StVZO regulation.
From wheel size 646mm(26") to 716mm(28"):
According to German StVZO, it requires 3V output at a low speed of 5km/h. If the 9 series is set on wheel sizes of 646mm(26") and 716mm(28"), it offers 3V output speed at 5.8km/h and 6.4km/h respectively. To have 3V output, it only needs to slightly increase speed up to 1.4km/h. Furthermore, according to German StVZO 6V3W regulation, it requires 5.7V output at 15km/h. If we set the 9 series on wheel sizes of 646mm(26") and 716mm(28"), this 9 series offers 5.7V output when speed at 15.7km/h and 17.7 km/h respectively. To have 5.7V output, it only needs to increase speed up to 2.7km/h. As for 6V3W, the German StVZO approved hubs in the current market normally offer 6V3W output when speed around 17km/h. The SP 9 series offers 6V3W output for 646mm(26") and 716mm(28") wheels when speed at 16.7km/h and 18.6km/h respectively.
To sum up, the 9 series with unprecedented dynamo characteristics is the perfect devise for 16" to 20" wheels. The extra values provided by the 9 series, such as its light weight and low drag, are definitely the great advantages for enjoying comfort. The ULTRASLIM dynamo can also work greatly for 26" to 28" wheel. Does increasing speed only 1 or 2 km/h matter? Only piece of cake. SP 9 series offers sufficient output and is definitely the best setup for going fast.
Shutter Precision not only seeks to become No. 1 in specifications, but also intends to closely monitor the quality of every single dynamo so as to ensure every dynamo is durable and reliable. Riding is simple. Technology makes riding simpler.
Shutter Precision hubs dynamos bring safety, convenience, comfort and the highest performance for riders. SP hub dynamos represent the best combination of technical achievements to meet the fundamental demands of a hub dynamo i.e. light weight, small size and high efficiency. The 9 series has demonstrated an enormous improvement from the preceding series. Innovation is all about self-breakthrough.