12 mm x 142 mm Axle Standard Explained

[Boeing]

Highlights from http://www.pinkbike.com/news/12x142-explained.html



The goal of a 12 x 142 mm axle standard is to make thru-axles as quick and easy to use as a quick release system

Stiffness of a 12 mm thru-axle, but with a quick release's wheel self centering feature

12 mm is the axle diameter, 142 mm refers to overall shoulder to shoulder width of hub (end cap to end cap)

Cassette and disc rotor are in the exact same relation to the hub's centerline as a standard 135 mm QR hub

Wheel dish remains the same as a 135 mm quick release wheel

Frame dropout's have 3.5 mm of inset per side that hub endcaps fit into - just as with a 10 x 135 mm QR wheel

There is not enough room on the driveside of a 12 x 135 mm thru-axle hub to build in the same hub locating ability, the extra 7 mm of overall width was required for the system to work

Whereas 150 mm rear hub spacing requires the use of an 83 mm bottom bracket shell for proper chainline, 12 x 142 mm produces the same chainline as a standard QR rear wheel and works perfectly with any variation of B.B. that you'll find on modern XC or AM bikes

Most hub manufacturers will simply make slightly different hub end caps to work with the new 12 x 142 mm spacing - no need to panic about having to buy a new rear hub or wheel

 

[Boeing]

anyone riding 142 rear thru?

 

[Master50]

Thanks for the 142 Primer. Since my current MTB uses really old axle and quick release a through axle will be on my next bike but this 142mm spacing will be a feature I look for. It can make a wheel change a lot like the QR method. Drop the wheel in and install axle. Only difference is the qr comes out with this method.
I suppose if I had the other 12 X 135 I might feel like the new standard is another pain but I can bypass that one and go direct to 142.

 

[papisimo98]

anyone riding 142 rear thru?

Yeah I managed to get one with out permission about 2 years ago on my Epic.
It's noticeably stiffer in the rear with the 142. It's really apparent when riding my other bikes which do not have the 142.
The automatic centering is a really nice part of the whole deal too. Yet, I'm always worried of screwing up the threads when trying to change a flat quickly.
Good stuff.

 

[biokemguy]

anyone riding 142 rear thru?

I did one of these conversions on a DT350 hub.
http://www.wheelbuilder.com/dt-swiss-x-12-system-142mm-conversion-kit.html

Works well, the only difference I notice is that it doesn't come loose like the old QR did.

I rode a friend's bike that had the frame designed for 142 thru so the axel screws directly into the frame/dropout (not really a dropout in this case).

I think that makes a bigger difference for stiffness of the rear end.

 

[Master50]

Just had a ride on my new MTB and it has thru axels front and rear including a 142 X 12. they work really well and taking the wheels off is as easy as quick releases but are definitely secure. I was imagining Rae Dawn Chong in American Flyers changing a wheel and 30 seconds later Kevin Costner is never to return to the peloton. With the coming of disks on road bikes I hope through axles don't catch on there.
I really cannot say the through axels improved anything but I like them and I can't see any problems with wheels pulling out of drop outs.
Can anyone tell us why downhill bikes need 150mm? Anything to do with moving the flanges out for better lateral strength?

 

[Eggcycle]

Are these secure while riding?

 

[Master50]

yes they screw in then finish like a quick release with a cam action.

 

[AcademyCC]

Just found literally the most amazing trail today. Came home. Passed out. Got up. Drank. And now cant think of anything but going to attack it again tomo. Incredible

 

[DirtyWorks]

I really cannot say the through axels improved anything but I like them and I can't see any problems with wheels pulling out of drop outs.

The twisting action on a traditional QR is very very dangerous with discs. Road bikes (cx too) must adopt the through-axle design on disc-equipped bikes. It is quick enough and irresponsible not to require the design on disc-equipped bikes.

I rode the through-axles this summer on a borrowed mountain bike and liked them well enough. They definitely have lots of mechanical and safety advantages over standard QR. On a mountain bike over bad terrain they make sense. I do not see the point of discs on the road WT, or even CX world cup.

 

[Master50]

DW
All my previous experience with disks have been pretty satisfactory with quick releases so I am not sure I agree this is essential. That said I am sold for many of the reasons and mostly because this system does really assure the wheel won't come out from driving or braking forces. I will ask for it on the tandem we are planning.

 

[DirtyWorks]

DW
All my previous experience with disks have been pretty satisfactory with quick releases so I am not sure I agree this is essential.

Yeah, we're getting into safety for a few who didn't quite tighten their skewers and then brake enough to loosen the skewer. I think everyone on the engineering/standards side realizes it's not a common thing, but what a terrible accident if it happened!

 

[Boeing]

Interesting that Norco designed their 2015 carbon cross Threshold around the 142 rear