Banzai

I’ll probably test it to find out when I get home anyway, but since I’m traveling right now I thought I’d ask.

I have an Alfine hub on a bike with track ends. I’d kind of like to use an axle puller on one side, something like the Surly tugnut, but it (and every) axle puller is incompatible with the notched anti-rotation washers fitted to the Alfine axle when mounted.

But if it will do fine with an anti-rotation washer on just one side…

Banzai

No one? I haven’t tested yet because I don’t want to damage anything. Shimano doesn’t have any guidance, but I imagine their guidance would be to always use two.

Obviously they designed it that way, but is it designed that way because it’s necessary for regular function, or because of redundant safety margin? The axle is all the way through, and so if it is stopped from rotating on one side, it should be stopped on both.

sweeks

I vote "No".
There must be considerable torque on the dropouts, and as they're aluminum I'd be concerned that a strong rider might be able to strip a single dropout.
But I'm no expert.

Dan Burkhart 

I don’t think the dropouts are the concern. Sachs/SRAM 5 and 7 speed hubs had axle flats for anti rotation on one side only. However, the internal actuation mechanism was entirely different from that of an Alfine hub. The Sachs hubs employed a sliding key whereas the Alfine hubs use a rotary actuation arm. Even the most minuscule twist on the axle could conceivably inhibit the free movement of the actuation arm resulting in only partial engagement of the rising pawls with possible resulting damage.
This is all theoretical as I have no empirical data. I do have several Nexus/ Alfine hubs in my fleet so maybe I should run some tests.
Also worth noting that Rohloff hubs have anti rotation bracing on one side only, but the design is more robust in every way.

sweeks

Thanks, Dan! I defer to your (much!) greater expertise.
I also have a couple bikes with Nexus and Alfine hubs,and I'm a pretty strong believer in operating these hubs as they are designed.
Maybe stripping a dropout is giving the torque too much credit; I wonder if the NDS is not held firm if it might result in the axle nut being loosened on the DS, with resulting shift in the wheel position.
If you do some testing, I'll be interested in your results.
Steve

Banzai

Thanks for the replies so far. Good stuff!

hartsu

I have a mks tug-nut installed on the inside of the track end and anti rotation washer outside.
https://www.velodrome.shop/chains/mks-ca-njs-chain-tug/

I don't have picture but here is mtbr member pursuiter's similar setup.
https://www.mtbr.com/attachments/tugnut-3-jpg.512334/

sweeks

I correct myself. I took my Alfine 11 off to repair a flat, and took a good look at the non-turn washers. There is no way one of those could be forcibly rotated through a dropout unless maybe the dropout were made of wax.
I'd still use them on both sides.