Difference between SON 28 and SON Delux hubs
The SON 28 dynamo hub delivers its nominal power of 3W from 15km/h, while the SON Delux reaches this power from 20km/h. The SON 28 dynamo hub is therefore recommended for applications requiring maximum power at low speeds, making it the model of choice if you want to recharge devices while driving.
The SON Delux dynamo hub is optimized to be as light as possible (by optimizing the winding and not by compromising the strength of the body) and to offer the least resistance to rolling. It therefore needs to turn faster to achieve the same power and will therefore be suitable for cycling at a higher pace or for bikes with smaller diameter wheels.
Compared to a classic front hub, the loss of efficiency at 25 km/h is less than 1% for the SON Delux and about 1.2% for the SON 28