Just wondering because I ordered a Quax 27.5 RGB and it comes with 137mm cranks. Being a noob, I’d like something a little longer, but it looks like my only option is to order out of Germany.Preformatted text
Technically Q-Axle is a proprietary system. But it looks suspiciously like Shimano Hollowtech, and those cranks seem to fit. 
(see here:)
But you would get extremely long cranks (because bike) and I don’t really think going to 145mm (biggest available from QX) would drastically change your riding experience… 137mm is a great size I think, try it before you change it.
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I have wondered the same thing because I have an older nimbus 20 inch that has q ax 125 isis cranks. They have nimbus painted on the front and q ax in raised letters cast into the metal on the back of each crank. I’m not sure what the hub is. Like I said it’s an older uni but definitely nimbus and has a UDC badge on the seat post neck .
You can switch out any Isis crank for any Isis cranks, doesn’t matter what brand made them.
So is the qu ax hub an Duff’s uni not issis?
Correct. They are using “Q-axle” now.
Q-Axle = Shimano propre design for hub / crank interface
I see , I have heard the term q axel used and did not know they where completely different. I’m curious are they a completely different concept or are they just different enough in size or number of splines so not to fit an issis hub? I’m an old vw guy and I know german engineering usually doesn’t allow for anything with a universal fit.
Read more about it here: https://www.qu-ax.de/en/2016/why-changing-q-axle/
Completely different system to Isis. As I said above, very similar to a Shimano system (but they probably can’t officially say that you can use Shimano cranks).
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Wow , I checked out the qu ax link, it does look like a Superior system, now I want to buy a qu ax. Thanks
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For me I had the same motivation, but if you want to play around a bit with different lengths (and purposes) you’re pretty limited by it.
The largest they sell are 145mm and then you can use e-MTB Shimano Steps cranks, which start at 165mm (just make sure you use the right version, starting at 8000).
I would like to try a 155mm to get the best of both worlds since I would like to take my 27.5" muni for brakeless offroad as well (where the brake is only a nice to have instead of a requirement if you go downhill). So maybe it’s a good idea for @qu-ax to add this to their inventory 
Thanks for all the responses. I’m sure that a few months from now the 137mm will be great. Currently though I like the extra leverage I get with longer cranks and the 165mm sound perfect.
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They actually do have 160mm versions available as well (at least in the US):
https://blueskycycling.com/products/shimano-steps-fc-e8000-mtb-e-bike-crank-arms
Only thing you need to keep in mind is that the lock plate must be removed from the Shimano cranks (just unscrew the back inbus, take out the plate and screw the inbus back in) otherwise they won’t fit your Quaxle…
Those have a different spline then the q-axle cranks
Looks like these have the same spline:
# Samox Hollowtech Crank Left 13 mm For Shimano E7000/E8000/E6100
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No they don’t, what you see in the image is the bolt you need to mount the crank before you tighten the regular bolts (look at the model number, it’s the same as the one you mention E8000).
Here’s a tool you could use to tighten that bolt:
But I actually re-used the bolt from the Qu-Ax system on the Shimano Cranks. You could even buy different colors of those bolts:
It’s only used to remove the play from the crank and the axle, it doesn’t actually have to secure the crank because that is done by the 2 inbus bolts on the side.
Thanks, that explains the different look.
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That’s awesome. I was afraid they were proprietary, because it seems sometimes Germans love engineering things even when they don’t have to.
That’s right, I just remember the German engineer who designed the pivotal seatposts for KH.
(No offence, I only feel uneasy with generalizations based on origin. Plus I am a German engineer
Pivotal seatposts are nothing new though. The Nimbus shadow handle has used them for a while, and BMX has been using them for a very long time now.
The biggest issue with the first Pivotal setups was KH Fusion Zeros used a hollow bolt that had a bit of a habit of snapping in two, especially if you didn’t have it quite tight enough.