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Boost axle fitted incorrectly ?

Maxi

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My MTB was built by distributor and delivered assembled. I want to change the rear rotors but am having difficulty removing the rear wheel - when I insert the 6mm allen key into the bolt, it is so tight that I can't loosen it. Having compared the setup with my old bike (Cube 160), I think the rear axle may be fitted incorrectly as the bolt is on the drive side of the bike whereas my Cube & older Trek have the bolt on the brake side. So which is correct - bolt on drive side or rotor side ?
 
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My MTB was built by distributor and delivered assembled. I want to change the rear rotors but am having difficulty removing the rear wheel - when I insert the 6mm allen key into the bolt, it is so tight that I can't loosen it. Having compared the setup with my old bike (Cube 160), I think the rear a...
@Maxi There's no single universal standard for which side the thru-axle lever or bolt head sits on. It varies by frame manufacturer. Some put it on the drive side, some on the non-drive side. Your Cube 160 had it on the brake side, but that doesn't mean every bike follows the same convention. So the fact that your new bike has it on the drive side isn't necessarily wrong, it's just different.

The real issue sounds like it's been torqued to within an inch of its life. A factory-assembled bike with an overtightened axle isn't uncommon, and the community has flagged similar things on Cubes before. A few things worth trying before you assume it's cross-threaded or otherwise problematic:

Make sure you're turning the right way (it's easy to second-guess yourself when the bolt's on the opposite side to what you're used to). Use a proper long-handled 6mm Allen key rather than a multi-tool, you need the leverage. If it still won't budge, a drop of penetrating oil around the thread and leaving it overnight can help break the friction. Also worth checking the axle hasn't been installed with threadlock, which some assemblers do apply despite it not being specified.

Once you do get it out, clean the threads, apply a light smear of grease, and reinstall to the manufacturer's recommended torque (typically 12-15Nm for a rear thru-axle, but check your bike's manual). That should make future wheel removals considerably less dramatic.

What bike is this, by the way? I can see you picked up a Cube Hybrid SL 160 from Jeffw, is that the one giving you grief, or have you got something new?

EDIT: @Dax reports Some bikes have the hex bolt on the mechanical end (derailleur hanger side) as part of the hanger assembly, with the axle securing from the other end. The user should check both ends of the axle rathe. Not yet independently verified — take with a pinch of salt.
 
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Bike is a Lapierre Overvolt AM 6.7 bought new from Pauls cycles. I don't think it's simply over-tightened as I can move the bolt but it doesn't become easier as I turn. It takes a huge amount of force to actually move it - I tried with my torque wrench at 28Nm and the wrench 'clicked' through it (i.e. force needed to move it was higher than 28Nm).
 
Bike is a Lapierre Overvolt AM 6.7 bought new from Pauls cycles. I don't think it's simply over-tightened as I can move the bolt but it doesn't become easier as I turn. It takes a huge amount of force to actually move it - I tried with my torque wrench at 28Nm and the wrench 'clicked' through it (i....
@Maxi Right, that changes things. If the bolt moves but the resistance stays consistently high throughout the entire rotation, that's not just overtightening. An overtightened axle would be stiff to break free but then ease off as you unwind it. Constant high resistance through the full turn points to one of two things: either the threads are damaged (cross-threaded or burred during assembly) or there's contamination or corrosion in the thread path.

Given it's a brand new Lapierre Overvolt AM 6.7 from Pauls Cycles, cross-threading during factory or distributor assembly is the most likely culprit. The fact your torque wrench was clicking through at 28Nm just to keep it moving is quite telling, a rear thru-axle should be somewhere around 12-15Nm when properly installed, so you're dealing with roughly double the resistance you should be seeing.

I'd strongly recommend not forcing it any further. If the threads in the frame are damaged and you keep driving it, you risk making a warranty claim significantly more complicated. This is a brand new bike, so Pauls Cycles should be dealing with it. Contact them, explain the symptoms (bolt moves but resistance doesn't decrease, requires 28Nm+ throughout rotation), and let them either fix it or replace the frame under warranty. If the threads in the dropout are stripped or cross-threaded, that's a manufacturing or assembly defect, not something you should be wrestling with in your garage. Take photos and keep notes of what you've tried, just in case you need to make the case.
 
Did you check the other end of the axle, some bikes have a hex on the mech end that’s part of the hanger and the axle secures on the other end
 
Did you check the other end of the axle, some bikes have a hex on the mech end that’s part of the hanger and the axle secures on the other end
Good shout, @Dax. Plenty of thru-axle designs have the axle threading into a nut or receiver on the drive side that's integrated with (or sits behind) the derailleur hanger. If that side has a hex fitting, it might be what's rotating rather than the axle actually unscrewing, which would explain the constant resistance with no progress.

@Maxi, worth checking this. Look at the drive side (mech side) of the rear dropout. If there's a hex head there, you may need to hold it with a spanner while turning the axle from the non-drive side. @Gary mentioned that on some frames the black nut above the derailleur hanger holds the hanger to the frame, and the axle threads into it. If that nut is spinning freely instead of being held in place, you'd get exactly the symptoms you're describing: loads of effort, bolt turns, but nothing actually loosens.

If that's what's happening, it's a much less alarming diagnosis than stripped threads. Get a hex key or spanner on the drive-side fitting, hold it firm, and try again from the other side. Should tell you within a quarter turn whether that's the issue.
 
Did you check the other end of the axle, some bikes have a hex on the mech end that’s part of the hanger and the axle secures on the other end
Yes - just a 'cap' on the other side. I can insert a 5mm key to its full length all the way in with no resistance.
 
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