Thru-axle
The thru-axle is a solid axle that passes through the hub and threads directly into the frame or fork, in closed dropouts. Its standard diameter is 12 mm (rear and road) or 15 mm (front MTB). It gives far more rigidity and safety than quick release and repositions the rotor identically. Careful: two «12×148» axles may not be the same, because total length and thread pitch vary by frame brand.
It's the modern standard: stiffer, safer and the rotor always in place. But buying the replacement has a catch.
What it is and why it's stiffer
Unlike quick release (which only clamps), the thru-axle threads into the frame and mechanically locks both dropouts, removing the risk of the wheel ejecting under braking. That rigid joint improves disc brake precision. It's tightened to a moderate torque (9–15 N·m). Its Achilles' heel is compatibility: hub width isn't enough, you need the right diameter, total length and thread pitch.
Key data
What it fits
It fits only frames and forks with closed threaded dropouts, and requires matching diameter, width, total length and thread pitch. It isn't compatible with open dropouts (quick release). Across brands, one frame's 12×148 may not work in another due to different length or thread.
If you don't know which axle, width or thread your frame uses, send us the case. Real diagnosis, nothing to sell you. Message us on WhatsApp
Frequently asked questions
Do two 148 mm frames use the same axle?
Not always. They can have dropouts of different thickness (different total length) or a different thread pitch (M12×1.0 vs 1.5 vs 1.75). Measure the original.
Is the thru-axle safer than QR?
Yes. By threading into the frame, it's physically impossible for the wheel to eject while it's fitted, and it repositions the rotor identically.
Can I switch my bike from QR to thru-axle?
Not by changing one part: the frame and fork must have closed threaded dropouts. It's a frame/fork change.