No , they are silent for all intents and purposes.
<insert tangent here>
Originally Posted by
Tourist in MSN
.......
When you first get your new dynohub, it is common to think that the bearings are adjusted wrong because by hand it is hard to turn the axle. .......
Not taking issue with TiMSN, just using that statement to setup my experience...
If there is any appreciable resistance felt with a SON28 then something is definitely wrong. I don't have experience with any other manufacturers hubs. Turning the wheel very slowly with it off the ground you get a slight bump.bump.bump sensation, nothing even remotely "hard". That is why I take claims that folks can feel the drag with a huge amount of skepicism. If you (not even going to use the word spin) turn the wheel slowly you can in fact feel it, if you put the bike on the ground and slowly roll it fwd you can't. I ain't buying the argument that people can add their weight to the bike and pedal and feel it then.
As far as the harmonic being translated to the bike through the fork, I think its possible but not probable as the amplification would have to be massive given the small input amplitude and the fact that it would be hard to hold speed precisely at that "magic number" to keep frequency stable long enough for it to develop.
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