Empowering The Bicycle Traveler

Shutter Precision Dynamo Hubs – New Product Spotlight

Even if you’re a close follower of developments in bicycle lighting technology, you may not be familiar with the new generator hub systems from Shutter Precision, or SP. However, we suspect that you’ll be hearing a good deal more about their hubs in the near future. With a background in the production of advanced photographic shutters for digital cameras and mobile devices, SP used their expertise in miniature electronics to develop a new dynamo hub system. The Taiwanese company began production in 2009 and now markets a line of hubs that rival the quality, performance and weight of the industry leaders at a surprisingly low price. We are currently stocking the PD-8 (6-bolt disc) and PV-8 (rim brake) hubs in 32 and 36-hole drillings with a bright silver finish.


Excellent finish quality and clean lines on the SP PD-8 and PV-8 dynamo hubs.

Given that my understanding of what actually happens inside a dynamo hub is limited, I won’t attempt to describe what goes on internally to set these hubs apart from the others on the market. It’s all magic and wizardry as far as I know. Despite my ignorance, I will risk some comparisons here.

SP claims that their 8-Series hubs (like the ones we have) deliver 72% efficiency at 15km/h (9.3mph), meaning that you as a rider are required to supply an additional 3.3 watts to generate power. If accurate, this puts the 8-Series in a dead heat with the highly-regarded Schmidt SONdelux, perhaps the industry’s benchmark for efficiency. In experiential terms, this level of drag is practically unnoticeable while riding. The Shimano DH-3N80 hub on my RandoGnar is supposedly only 53% efficient – requiring something like 4.5 watts at 15km/h – and I often find myself riding around with my light on in the daytime after neglecting to switch it off the night before.  

In terms of weight, the 8-Series hubs are also right on par with the Schmidt. SP claims 390g for the rim-brake version and 410g for the 6-bolt unit. Schmidt gives an identical weight of 390g for the SONdelux and 395g for the Shimano-compatible CenterLock disc option. Shimano claims a weight of 490g for their lightest offering.  These numbers also put SP at the top of the class, regardless of price.

Okay, so they’re efficient and lightweight. That’s a good start, but all the high-tech internals in the world don’t matter if the thing isn’t reliable. SP backs all of their hubs with a two-year warranty against defects. They have survived the rigors of the Tour Divide and numerous other long, arduous races and tours without issue. In the hand, they feel just as sturdy and well-made as the Schmidt units. They spin on high-quality cartridge bearings rather than the cup-and-cone systems that Shimano uses in their hubs. Unfortunately (as with all dynamo hubs, to my knowledge) the bearings are not replaceable or serviceable by the user. However, the hub can be returned directly to the factory for bearing replacement if they ever wear out. If within the warranty period, this service will be performed for roughly $30 US including shipping.  The SP hubs also use a connector very similar to Shimano’s which makes installing wires, removing and installing the wheel a simple matter.


SP’s wiring connector, shown here still partially disassembled.

Okay, so let’s get down to dollars and sense here. A dynamo lighting system is no small investment and we all want to be sure we get the best our budget will deliver. For the price-concious consumer who still prizes performance, the PD-8 or PV-8 will be difficult to top. This may be the new standard for bang-for-your-buck in a dynamo hub, bar none. We’re selling them for the very reasonable price of $123.97. Compared to the $300 price tag for the SONDelux, this an amazing value. Shimano’s Alfine or DH-3N80 hubs cost almost exactly the same as the SP but are less efficient and likely to be less durable.  These were formerly the best alternative for anyone who didn’t want to spring for the SON but are clearly outclassed by SP.

So why should you buy anything else for your dynamo build if these hubs are so great? I’ll have to leave that to you to decide for yourself but I’ll offer some food for thought. Perhaps the single biggest factor setting the Schmidt offerings apart is the five-year warranty compared to two years from Shutter Precision.  Schmidt uses a “smart pressure compensation system” to prevent the buildup of condensation inside the hub shell which can lead to corrosion or freezing of the generator parts over the long haul, allowing them to offer such a generous guarantee. It is unclear wether SP uses any similar technology in their hubs. Aside from this discrepancy, the other differences are fairly subjective.

SP is a relative newcomer to the business, so despite their excellent track record so far they are relatively untested over the long haul. Some brand-oriented customers will prefer the prestigious Schmidt name or the tried-and-true Shimano.  Also, there’s no avoiding the fact that these hubs are made in Taiwan. We all know that lots of really nice things are made in Taiwan, so quality isn’t the issue. I can’t speak to the ethics or sustainability of Shutter Precision’s business practices, so I’ll leave that judgement to others. Regardless, many consumers would rather put their trust in a German-made product. Prefer Shimano’s CenterLock disc rotors?  You’re out of luck with SP unless they decide to license that technology in the future. Also, our stock is currently limited to the aforementioned PD-8 and PV-8 in silver with 32 and 36-hole drillings. SP offers a wide range of other models, colors and drillings but availability is currently scanty in the US.


Overall, Shutter Precision is an exciting new player in the dynamo hub market and we’re happy to be able to offer these hubs to our customers. No product is perfect, but we think the ratio of price to performance they offer is exceptional and are looking forward to getting them laced, wired and between the dropouts of some bikes in the very near future. Shoot us an email or give us a call in the shop if you’d like to talk about wheel build options or a lighting setup for your bike.

14 comments… add one
  • Bill Lucas November 17, 2014, 10:02 am

    My wife has had a 32 hole PV-8 on her commuter for 2 years. It has performed without issue. I was concerned about the 50 mm flange spacing, but the wheel built up nicely and hasn’t needed attention. She rides with a too heavy handlebar bag.

  • David Spranger November 24, 2014, 7:33 am

    I have had a 32h PV-8 on my A. Homer Hilsen for around 2 years as well. It has performed it’s duties flawlessly. As someone who is mostly NOT brand conscious, but am very quality conscious, I have used the dynamo hub offerings from SP, Shimano, Schmidt and Sanyo on various bikes for many, many miles. Reliability has not been an issue on any of these hubs. I do have to service the Shimano hubs every couple of years (FYI, the factory bearing lube is not adequate in the Shimano hub). To my perception, I really don’t feel any difference in drag between any of them. I leave my lights on whenever I ride, day or night.

  • John Saxby November 24, 2014, 10:50 am

    Hi folks, Thanks for the notice — good to know that you’re offering the SP hubs. They seem to be building a good rep, and their price is very attractive.

    One question: can the SP hub power both a headlight and a charging unit? I understand that the SONDelux cannot do this — if you want this capacity from a Schmidt hub, you need the SON28. I have the SON28 on my new (one-year-old) touring bike, and after a year, the SON28 has performed flawlessly. Mine is hooked up to both my headlight and a Sinewave charger, and will power either device, or both at once. When the hub is powering both devices, the recharging function slows down.

    • Ryan King November 25, 2014, 8:24 am


      Thanks for the comment and your thoughtful question. In my understanding (and I may be corrected on this) the reason the SonDelux struggles to provide enough power to run lighting and charging systems is that was originally designed for use in 20″ wheels and optimized to turn at higher RPMs. When laced into a larger wheel, the hub turns fewer RPMs at a given speed so it requires the bike to move faster to reach full output. With the small power requirements of modern LED lights the generator does not need to reach its full output at low speed so Schmidt rebranded the Son20 as the SonDelux to broaden its appeal. The slightly reduced output is not a problem for most riders and results in a more efficient hub. I’m not certain what rate of speed or RPMs are required to reach the hub’s full output but if you maintained that speed you should be able to power lights and charger using the SonDelux.

      As for the SP, I would expect the experience to be similar to what you’ve described with your Son28. The hub is designed for the lower RPMs of larger wheels and should reach full output at reasonably low speeds. The exact speed required will vary somewhat based on the outer diameter of your wheel (faster for fat-tired 29ers, slower for skinny 26″) but I feel confident saying that you should have no problem powering lights and charger at normal riding speeds with the 8-Series hubs. In my experience with other generator hubs, the power output drops somewhere around 8-9mph and causes lights to dim and charging to slow. I’d expect similar performance from the SP. We’ll be able to speak more to this issue after some road testing. Perhaps someone with personal experience can chime in here in the meantime.

      I hope this helps. Feel free to get in touch directly if you have any other questions. Thanks for reading!



  • Phillip Bissell, Australia November 30, 2014, 9:18 pm

    Congratulations Jim, on going into SP Dynamo Hubs. I have two, which have been in service for a year or two – one on my touring bicycle, the other on my roadster. Cannot speak too highly of them. Certainly great value and they live right up to the claims made for them by Shutter Precision. Like Bill Lucas above, I was somewhat concerned by the narrow flange spacing, fearing a possible lessening of lateral strength in the wheel. However, the all-up weight of touring bicycle+baggage+rider is something approaching 180kgs and the wheel has not collapsed.

  • Myrddyn kruse November 5, 2015, 6:48 am

    Hi there
    Does the sp have an on and off option or is the drag so little that it doesn’t matter. Really considering getting one of these hubs. They sound good

    • Bike Hermit™ November 5, 2015, 9:30 am

      If you have a switched headlight there is more drag on the hub when the light is switched on. The hub itself does not have a switch. There is always a little bit of drag in the hub but it is really not noticeable on a built wheel on the bike. If you grab the hub by itself- not on the bike- and try to spin the axle it feels notchy, like a poorly adjusted cone and bearing hub. This is normal. Shutter Precision claims theirs is one of the most efficient dynamo hubs on the market.

  • Greg Andre-Barrett February 9, 2016, 2:55 pm

    I’ve heard that SP PD-8X had bearing failure issues by several on the Tour Divide and other races. Is this true? I’m buying a dynamo to do the Tour Divide and can’t afford a failure.

    • Bike Hermit® February 10, 2016, 9:46 am

      We have had exactly zero warranty issues or problems with the hubs we have sold. (knocking on wood as I type) Where did you hear about the issues?

      • Rick Harker March 1, 2016, 10:50 pm

        I’m on my 4th SP hub. 2 have had failed bearings and I’m sure it is because of moisture ingress.
        I’m guessing that there may be a pressure issue when water hits the hub the contraction of cooling air within the hub sucks moisture in through the seals just as it happened with SON before they fixed it.
        The repair process is obscure too. Pay first and then send your hub to Taiwan. Not very assuring.
        The other 2 units I’m using are PV-8. One is disk but the non disk version which is an early unit has more apparent drag both when spinning in similar wheels and on the road particularly over 30kph.

    • morgan h November 16, 2016, 9:32 pm

      I purchased a SP hub which performed great for about a year before bearing failure. I took to local shop Carytown Bicycles for repair and was told the warranty was voided by my purchasing on ebay and the shipping to Taiwan was $140 each way if I wanted bearings replaced. That was a few years ago so perhaps policies have changed (if so I’ll replace ) but I would check into it before getting sunk.

      • Ryan King November 17, 2016, 7:52 am

        Howdy, Morgan!
        Thanks for your report. Sounds like a frustrating experience. I’m wondering if sealing systems or bearings have been quietly improved since then as we’ve had no reports of bearing failure on hubs that have passed through the shop. Thanks for reading and sharing!


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