Rim upgrades and Dynamo decisions

[Aushiker]

I am looking at a dynamo build for the Giro 20 and probably an upgrade of the rear wheel while I am at it.

I want to be able to run 28 mm tyres as a commuter/Audax and I can use the existing Alex DA 16 as a touring wheel for now if need or probably just fit wider tyres to the new rims. So that means, it seems from the current Velocity offerings, a Velocity A23 or Aeroheat married to XYZ dynamo. Sound fair? Other suggestions?

The A23 20" is 290 grams and 23 mm wide and the Aeroheat 20" is 24 mm wide and 330g. The A23 is a more aerodynamic profile. Both are available in 32 spokes. I must admit I am not 100% sure what is the big difference between the two rims.

Mmm maybe a A23 on the front and a Aeroheat on the rear is the way to go.

Getting back to the subject of a dynamo, it seems that the choice is between SONdelux and a SP SD-8 or PD-8. The SD-8 has a reported weight of 385 grams (PD-8 weighs 410 grams) versus the SONdelux coming in at 395 grams plus adaptor for a six bolt rotor which I need. Not a fan of Shimano dynamo hubs (I have one) so not going down that path here.

Not much difference weight wise, five year warranty on the SON, price is AU$362 whereas the SP SD-8/PD-8 ex Taiwan is AU$152. I think that might settle things even though I really like my SON hub on the Surly.

Interesting the eBay SP seller recommends the PD-8 for 20" wheels.

Owners of bicycles with 20" wheels. We recommend the P series hub dynamos even for 20" wheels as they will produce more power/light at lower speeds. The risk of burning out lamps is unlikely as modern dynamo LED lights have in-built voltage limiters. I run a PD-8 on my Bike Friday without problems and can hardly notice the additional drag. If you plan to recharge electronic devices, the extra power is a key benefit available only to 20" wheel bicycle owners.

So any thoughts on the rim choices and anyone have experience with the Shutter Precision dynamos on smaller wheels?

Andrew

 

[Recycle]

I have the Son delux on my speedmachine and the SP SD-8 (or PD-8) on my grasshopper. Both are excellent dynamo's although the Son has less resistance (If I spin the wheels the Son wheel will rotate for longer than the SP). That said, the SP resistance is very low and I'm not sure you would notice it. I'm not sure the Son is worth the difference in price. Both work very well with a 20" wheel.

The only thing I don't like about the SP is that the spoke flange is a different diameter on each side so you need to use different length spokes, which makes the wheel build more awkward.

This site has some excellent (non-commercial) reviews on dynamo's and lights: http://swhs.home.xs4all.nl/fiets/tests/verlichting/index_en.html