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Tested from: To come, hub to be spoked in. Got it mid Jan. 2014
On the main page I wrote:
2013-7-5: SP's upcoming PD-8X dynamo hub is for the new market of 15mm axles, but it's supplied with an adapter for standard fork ends. For this hub SP has redesigned the dynamo part resulting in a claimed increase in efficiency of 7% over the PD-8/PV-8. This is an incredible achievement if true... I talked to a friend of mine yesterday who was at SP and they showed the difference in action, but note that though such an increase in efficiency is technically a big deal, in actual use it won't be. You just won't notice the small losses of just about any dynamo hub (see the calculations at the end of this page to show that half a Watt won't slow you noticeably down, wind has much more effect...) Well, except in that the more loss, the more power you must provide and this results in stronger jolts. So the efficiency increase could mean that a 26 pole hub (if it is 26 pole, not sure yet) is equivalent to a 28 pole hub in jolt strength.
Mass: 422 g, 455 g with standard axle converter.
Dimensions of spoke hole circles etc.: Same as PD-8? (left: ?? mm, right ??mm)
Pictures to come.
A few months ago I was told by a friend of mine who already had a PD-8x that the rotation direction makes a difference in how strong the resistance to turning it (at each pole) is, and I can indeed feel this. In the rotation direction to be used, the hub can be rotated more easily than the other way around. Will this mean that vibrations in the handlebar are less than the PD-8? The efficiency increase should also help in this respect, but I will see when I do my test.
The hub's price is about $200, and I was told that the main reason for the price difference with the PD-8/PV-8 is the increased cost due to narrower tolerances of the components and in the build process of the hub.
The hub that I have doesn't have an StVZO approval number yet.
The hub comes with an adapter for standard axles, and rotates freely inside the hub. Neither has any ridges to grab the fork, so how will that work? Will there be enough friction to make sure the hub doesn't rotate in the fork?
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Last modified: Thu Jan 23 14:51:58 CET 2014