The unrivalled SON dynamo hub (or Schmidt Original Nabendynamo, to give it it's full title) has a new model available this month.
The 20R is a lighter version of the SON 20, which is designed for bicycle wheels of 16" to 20" in diameter.
The SON 20R has the following specification:
- Power: 6V/3W
- Efficiency: 60% at 15km/h in a 20" wheel. 65% at 15km/h in a 28" wheel.
- Power consumption (under load): 0.7 W at 15 km / h (in a 20" wheel)
- Power consumption (under no lighting load): 0.4 W at 15 km / h in a 20" wheel)
- 26 pole magnet.
- Hub Sleeve: aluminum 6082 T6 polished or black anodized
- Spoke holes: 36, 32, 28, 24, 20 (radial spoking allowed)
- Two 4.8mm electrical contacts
- Weight: 390g (compared to 580g for the existing models)
- 5 year warranty
A model for disk brakes is under development and should be available in February 2008, and the 28" model should be available in October 2008.
There seem to be no plans to update the SON XS, which is a narrow version of the dynamo hub, designed to fit the narrow front forks of a Brompton and New Series Moulton.