Last week I did some wheel building.
(Don't mind the toilet paper, we were out of napkins)
Through the valve stem.
And on the bike.
A few of my friends in Pittsburgh have set up dynamos on thier touring bikes. And after hearing how well they worked, I figured that they made a lot of sense for bikepacking too. Now I'll always have light, and I'll be able to power my iPhone.
That constant supply of power will make it possible to run the Gaia GPS app constantly on Tour Divide (in tracking mode, the GPS normally drains a battery in about three hours). I also use my phone as my only camera.
Since I almost always have the iPhone anyway, might as well use it to it's full potiential. Especially since the dynamo wheel ended up being cheaper than buying a new camera and GPS.
The dynamo is a Shutter Precision PD8, which was $130 on ebay, with free shipping from the ROC. Those guys make hubs for Supernova (one of the only options in QBP), and for Exposure, so their designs are solid.
It's also the lightest dynamo out there, and it looks nice. And at half the price of a Schmidt, it was a no brainer for me. I'll be interested to see how it holds up long-term, but I'm betting it'll be fine.
I would like to figure out if there's a way to easily sevice the bearings, but that probably won't be an issue for a while in this dry climate.
This Exposure Revo came from a guy on the Bikepacking forums, and it looks like it didn't get used too much. Supposedly it puts out 800 lumens on full power.
The power increases as I ride faster, so I'm not sure what speed I need to be rolling to see full power, but it doesn't really matter. The light puts out enough light to ride comfortably at almost any speed.
The Revo has a power output port on the back, and the guy I bought the light from included a USB boost cable. Unfortunately, it won't charge an iPhone. Not at all.
Apparently it will charge an external battety pack, which can be used to charge the phone, but I don't think I want to go that route.
Using the output port on the light means that the light has to be on- so most of the power from the hub is going to the LEDs, instead of charging the battery.
I'm probably going to end up ordering a Sinewave USB charger, and wire it alongside the light. If anybody has experience with this stuff, I'd be glad to hear it.
The beam at about 12mph:
Riding fire roads and pavement is great. At a little below 10mph all four LEDs kick on, and put out more than enough light.
Buff singletrack would be fine too. But technical singletrack, where my speed stays below 4mph is a little tricky. That's only fast enough to power two of the LEDs, so it feels a little like riding with a AA powered commuter light.
With a USB rechargable helmet light (which could be recharged durring the day with the hub), I'd have plenty of light for trail riding. The helmet light would pick up the dynamo's slack at low speed, then at high speed, the Revo would outshine the headlight.
I'm really picky about how my bike rides, and can tell if my tires are off by 1psi when I'm on singletrack.
The SP hub feels notchy out of the box because the magnets are so strong. On the bike, I was really trying to notice the drag.
But it just isn't there. Even under load (light on), it rolls just like a wheel. It feels absolutely the same as a normal hub. No shuttering or roughness. I'm pretty stoked about that.