Excuse me if this question has been posted before, I did a search and didn't come up with anything about this make of hub. Does anyone have one of these?
I'm building a new commuter up from scratch (first time I've ever done that) and decided to try a dynamo hub. I have a good light set, but was curious about them. So, i bought an Shutter Precision model PV8 from an overseas buyer. It's arrived and looks to be a quality piece of machinery, so I was a bit startled, when turning the axle by hand, to notice how rough it seems - as if it's clicking on gears internally.
Is that how it's supposed to feel? The last time I had a dynamo of any kind was about 25 years ago, a Sanyo bottom bracket generator that was quite a neat little item before it stopped working. I still have it and it doesn't feel like this.

yes. magnets are strong so you get the notchy feel.

I think that's due to the strength of the magnets. It's a very efficient hub, so it's really a non-issue. I have a variety of dynohubs, the cheap ones are horrible to turn and also inefficient. Once you get it on your bike it's not going to be noticeable most of the time. There was a thread about vibration recently, I expect that the SP hubs will also vibrate at some speed or another

I have had one and used it for about Months now. The strong magnets make for the notchy feel but once the wheel is built up you will notice a substantial difference. Once on the bike (we use ours on a tandem)I don't notice it at all.

I had the same question when I got a wheel built on an earlier SON. But on the bike with lights on, it's a gentle buzz, and the bike rolls very smoothly with long coasting distances. Probably not as long as my road bikes with nice racy tires and nice, smooth Campy hubs, but pretty darn long.

The electrical construction of all these generators is similar, and they all really should show some notchiness.

FWIW, the notchiness itself doesn't cause drag. When the magnets and poles are aligned it takes some work to turn the hub, but when riding that work is return when the hub pulls into alignment with the next pole. Some design are a bit less notchy because they employ more closely spaced pie-shaped pole pieces, which can reduce perceived vibration under some circumstances.