Boost 15x110 axle
The front 15x110 Boost axle is 15 mm diameter × 110 mm wide. It replaced the older 15x100: the greater width spreads the hub flanges apart, giving a stiffer wheel and more clearance. The key point: a Boost fork needs a Boost hub, they're not interchangeable without the correct hub (and disc alignment must be respected). If you have an old 15x100 hub, first check what fork fits your bike.
Boost has become the usual front standard, and mixing it up with a 15x100 hub is what leaves the wheel unmounted. Here's what you need to know.
What it is and what changed
The numbers. 15x110 means a 15 mm axle diameter by 110 mm width between dropouts. The diameter (15 mm) is the same the old 15x100 had; what changed is the width, from 100 to 110 mm.
Why it got wider. By spreading the hub flanges further apart, the wheel is better triangulated: stiffer and with more clearance. That's the whole point of Boost. That's why it replaced 15x100 as the front standard.
The detail that matters. A Boost fork needs a Boost hub. They're not interchangeable without the correct hub, and when mounting you have to respect disc alignment so the caliper lines up with the rotor.
Key facts
What it pairs with
To get the purchase right, first check what fork fits your bike and, if you're going to touch the suspension, how much travel you can run. The part that decides the real axle compatibility is the hub: it has to be Boost to match a 15x110 fork.
Send us your front hub and fork measurements and we'll tell you if they match. Message us on WhatsApp
Frequently asked questions
What does 15x110 Boost mean?
A front axle of 15 mm diameter by 110 mm wide. The 110 (Boost) replaced the older 100. Wider = stiffer wheel and more clearance.
Can I fit a 15x100 wheel in a Boost fork?
Not directly: a Boost fork needs a Boost hub. The diameter is the same (15 mm) but the width changes. They're not interchangeable without the correct hub.
Why did it move from 15x100 to 15x110?
Because widening the hub to 110 mm spreads the flanges further apart: stiffer wheel and more clearance. Boost became the front standard.
Related
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