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Dynamo hub-12mm Thru axel and centre lock

Posted: 13 Jul 2018, 10:55pm
by martinn
Hi all,

Having recently purchased a disc braked thru axle "Winter" bike, I am looking to replace the front wheel with a suitable dynamo version.
This will be doing most of the more "inclement" weather rides, mostly 200Km with a few 300Km thrown in is as well. So dynamo lights just makes life easier in my view, as well as giving the option to charge a device. (I do appreciate that some of the battery lights would suit this purpose as well, and a battery to charge a device)

So of the three options out there, which one?
Son 28 12, Son delux 12 or SP PD8X, the Son delux is the lightest, all seem to give the same power, the SP is apparently the most efficient at 75% vs 65%
SP is the cheapest to purchase, but I have destroyed a previous SP hub.
I think, but its not really stated that the difference between the delux and the 28 is the way they power at low speed, and high speed. With the 28 being best for lower speeds.
there also seems be some comments that the 28 is better at powering lights and charging a device, at the same time.
I cant really find much info on these.
Has anyone any experience of these particular hubs?

Thanks
Martin

Re: Dynamo hub-12mm Thru axel and centre lock

Posted: 13 Jul 2018, 11:24pm
by Brucey
SP hubs are not usually as long-lived as SON ones but since they can be rebuilt in the UK for a nominal sum (£25 I think) I no longer have a massive downer on them.

The efficiency claims may well vary with who is doing the measuring and what kind of load is being used. On the SP website they claim that the lights off drag is less than with 'a German brand' and show a video that backs this up

http://sp-dynamo.com/8seriesdynamo%20hub.html

I doubt that you would notice a 10% change in efficiency with the lights on, BTW.

cheers

Re: Dynamo hub-12mm Thru axel and centre lock

Posted: 14 Jul 2018, 11:06am
by martinn
Thanks Brucey

the Video is a comparison between a Japanese brand and SP, so not helpful and to be honest doesn't really seem to be that different.
The comparison charts that SP use to compare with a well known German brand, show that with the SP hub, the difference in power required when the lights are on or off is about 0.5W, and that even when on the power drain is only around 5W
To be honest could I tell the difference? Definitely not the 0.5W, possibly psychologically the 5W when you are climbing a long steep hill! But in reality, I don't notice the difference at the moment.

So does it come down to price, as all things are probably equal, or does one build into a slightly stronger wheel if using the same RIm and spokes?
And which between the two Sons? there must be a difference otherwise they would not have made two products

Martin