SON 20R on a 26" Wheel

[stutho]

I have read in a few places on the web about using a SON 20R on a normal wheel.  The idea being that because they are designed for the faster rotation of a smaller wheel they actually have less drag (than a SON 28) when used on a normal wheel.  The downside is that you have to be moving slightly quicker than with a SON 28 before full power is reached.

Has anyone any experience of doing this?  One site is calming that this is now the preferred option for Audax riders!  Is this the case, or is in more internet babble?

Stutho     

[PH]

This review was suggesting that for fast riders a few years ago and that was with halogen bulbs, LEDs reach full brightness at much lower speeds making it feasible even for the not so fast.  According to the sales blurb the E3 reaches 90% output at 4 -5 mph with the SON 28 and at 6 - 7 mph with a SON20,  Supernova build their road wheels with the 20. Schmidt seem to be saying the same thing here though my German's not good enough to be sure.  In practice I can't tell the difference between 90% brightness and 100%, all the modern dynamo LEDs seem to produce plenty of useful light as soon as you're moving above walking pace.  On the other hand, I can hardly feel the drag from my SON28s, I'd probably go with a SON20 if buying now, but I certainly don't consider it worth changing.

[Dave Whittle Thorn Workshop]

As said above its fine to use the SonR with larger wheels, you need to use with an LED dynamo light nowadays though you'd be mad to use anything else.

The only time not to use it is if you are using for loaded touring as the flanges are spaced closer together building a wheel thats not as strong, also note you have to unbuild the wheel with a 20R for Schmidt to service, but this isn't very often anyhow.

Dave Whittle

SJSC Sales

01278 441542