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17

When carbon manufacturers and fabricators put holes in things, they're thinking about: Whether disrupting the continuity of the carbon layers in that way will leave it strong enough. Whether there will be enough material left to be strong enough. How to reinforce and finish the hole to avoid problems with fraying, moisture, and stress risers. The answer to ...


9

I would assume it is not safe to drill into carbon, not at that location. I am not saying that it is not safe, only that I strongly suspect so and that I am not willing to assume otherwise. To state the obvious, when you drill holes in something, you weaken the structure. A heavier fork may be overbuilt and it might be fine, but you don’t really know if the ...


8

Remember a dynamo hub has a small electric generator inside of it. What you are feeling when you turn the shaft is the interaction between the magnets and wires in the the generator creating peaks of torque on the shaft.


6

I faced exactly this question about a year ago. I did all the internet research I could, talked to bike mechanics and emailed fork builders and repairers. The answer that emerged from all this was a clear 'no'. The fork crown is subject to large forces and drilling it will weaken it unpredictably. The one thing that's worse than not having a sweet USB ...


5

Asymmetrical rims raise the weaker side tension and reduce the bracing angle disparity on wheels where the hub has a different center-to-flange distance on each side, as long as the amount of offset at the rim in question brings the dish closer to center than the offset at the hub moves it away from center. SON28 disc hubs have smaller and closer to ...


4

IF you do drill a hole, I would suspect that going straight down the steerer tube (ie radially out of the tyre) would be better than drilling in through the side of the steerer tube. Firstly, you're likely to interfere with bearing seat, and then the material covering the "floor" of the tube is probably not that thick nor structural. You need to ...


4

I now suspect this is a vestigial hole. I took apart the older version of the same light and found that on that one (which has a 2-conductor cable leading out from the hole), the wires inside are actually soldered onto the back of the main board. I could not determine where the current went along the board from that point, as I was only looking at the back ...


4

The apparent turning resistance, and the presence of discrete resting positions is normal for dynamo hubs. When I first got my Shutter Precision PD-8 dynamo hub, I was shocked that I could barely turn the axle with my fingers. However, in operation the effective resistance of the hub is negligible as you would expect. The "cogging" between ...


4

I've built quite a few of these. They work very well. They are bulkier, heavier and marginally less efficient than the SP hub but have a good reputation for reliability. As far as servicing goes, due to the complexity of the electronics within the hub and the necessity for components to be perfectly aligned, dynamo hubs are usually considered a closed box ...


3

Yes, they don't care, you can use any QR you want. I've used an early SON28 with the stock one, a Pitlock, an external cam light skewer, and various Shimano skewers, and a current SONdelux with the stock one and a Shimano QR. It doesn't matter. I don't know the numbers but I believe internal cam skewers develop quite a bit more clamping force than bolt-down ...


3

Won't matter much, 22AWG is rated at about 1AMP for power transmission and 7AMP maximum current (i.e. that is around the current insulation starts to melt), is plenty large enough to carry the current from a dynamo (a few hundred milliamp's) and provides a strong enough wire that it won't break easily when in use. A size or two smaller or larger won't hurt.


2

I finally got this done. The procedure is as discussed in the chat for this question. Open the light by unscrewing the two torx screws on top. (Be careful not to lose the rubber washers, they're transparent! Take a photo of how things are arranged and connected inside. Putting the thing back together is a bit like playing tetris blindfolded. Disconnect the ...


2

I eventually contacted Supernova and, contrary to Cube, they replied almost immediately. They said that in order to get rear stand light functionality with their front light, you have to use their rear light only. This is what I did actually. I bought their rear light that mounts on the seatpost and connected it to the front light by cutting the wire that ...


2

In 2014, Mike Hall finished the TABR ~20 hours ahead of the second-place finisher. Dynamo hubs impose a drag of 1–6 W when they're disengaged, and 1–25 W when engaged. There's a fair amount of variation between hubs, and in the loads that different headlights impose on them, and the loads vary with speed. Ride Far has an analysis of how much time dyno hubs ...


2

Another option I’m thinking about trying would be to use an e-bike with regenerative braking and USB power output, like the RadCity, and put it in a bike trainer stand without connecting the wheel to the resistance element. Then just set the e-bike max speed to some low value (the Rad bikes go as low as 12kph) and start pedaling. The regenerative braking ...


1

You don't have a choice about needing to cover the bare strands. So you are going to need to get a piece of heat shrink for the outer that when shrunk will be able to play nice with the hole in the connector. The connectors are only a few dollars if you screw one up (aside from the hassle of getting a new one) so I think the answer is don't be shy about ...


1

One other consideration is that it's cheaper to have different wheel setups (eg. one for winter and one for summer) with a bottle dynamo. I for sure would at least look at a bottle once my shimano hub dynamo wears out :)


1

Is the dynamo single terminal or two terminal? (12V bottles usually have two: a 6V terminal for the taillight and a 12V terminal for the headlight and "6V 0.05A" sounds right for a taillight.- assuming a vintage dyno using frame earthing... A modern european dyno would use a discrete earth wire and 6v headlight) I would suggest trying a 12V 0.4A ...


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