The original Freakynuts 15mm Adapter for the Fox40. CNC-machined from 7075 aircraft-grade aluminum in Germany. Trusted by thousands of riders worldwide.
Why We Built the Fox 40 15mm Adapter
Every mountain biker knows the problem.
Your trail bike, enduro bike or e-bike uses a 15×110 Boost front wheel, while your Fox 40 downhill fork still requires a traditional 20×110 axle.
Buying a second front wheel simply doesn’t make sense. So we designed the solution ourselves.
Not a cheap sleeve. Not a universal compromise.
A completely engineered adapter system that allows you to ride your existing 15mm Boost wheel in your Fox 40.
Built for people who ride hard.
CNC Machined in Germany
Every Freakynuts® adapter is manufactured in Germany on state-of-the-art HAAS CNC machining centres.
Every part starts as a block of premium 7075 aircraft-grade aluminium, one of the strongest aluminium alloys available.
Why 7075? Because downhill riding doesn’t forgive weak materials.
It offers:
- Exceptional strength
- Maximum stiffness
- Outstanding fatigue resistance
- Long service life
Every adapter is machined to extremely tight tolerances for a perfect mechanical fit.
Precision That You Can Feel
Cheap adapters rely on oversized tolerances.
We don’t.
Our adapters are manufactured with extremely precise fits.
That means:
✅ Zero unwanted movement
✅ Perfect clamping
✅ Improved steering precision
✅ Better braking feel
Every component fits exactly where it belongs.
No Saw Cut. No Weak Dropouts.
Making a saw cut in an adapter so it can clamp or any other wierd thoughts? We consider that an unsafe and unacceptable solution.
We refuse to use this kind of hazardous design. A truly solid system is achieved through extensive testing, extremely precise tolerances, and the use of the highest-quality materials manufactured on the best machinery. That is how we ensure the strength, reliability, and safety of every product we make.
The Freakynuts® system uses an entirely different engineering philosophy.
No clamp saw cut. No weakening of your fork. No irreversible modifications.
Just a unique design developed entirely in-house.
The secret of the blacksmith stays in Munich.
Three Versions For Every Rider
1. Basic Adapter
Perfect if you already own a quality 15mm Boost thru axle.
You receive only the precision adapters. Affordable. Simple. Reliable and you can use your own 15x110mm Thru Axle with a length from 175mm.
2. Pro Kit
Want maximum stiffness?
Choose the Pro Kit. Includes our KingPin 175mm solid 7075 thru axle.
A completely solid Extra-long Axle is added to the Basic Kit. Extremely rigid. Perfect for aggressive riding.
3. Premium Kit
This is the flagship.
The Premium version combines the adapter and axle into one innovative two-piece system. Less loose parts. Maximum rigidity. Better load distribution..
Simply put:
Bomb Proof.
Designed for riders who trust their equipment on the biggest jumps and fastest descents.
Rampage. Bike Parks. World Cup tracks. No problem.
Available in Multiple Anodized Colours
Performance is one thing.
Style matters too.
That’s why the Freakynuts® Fox 40 Adapter is available in multiple premium anodized finishes.
Choose the colour that matches your bike.
- Black
- Gold
- Raw Aluminium
More colours continue to follow.
Tested by Thousands of Riders Worldwide
The Freakynuts® adapter has been used by riders across the globe for years.
From weekend trail riders to freeriders and downhill racers.
Thousands of successful installations.
Thousands of happy customers.
One proven system.
Worldwide Shipping
We ship worldwide.
USA Customers
Orders inside the United States are shipped from our Colorado warehouse.
Benefits include:
- 🇺🇸 Free USA Shipping
- No Import Duty
- No Customs Fees
- Faster Delivery
Visit our dedicated US Store:
👉 15mmForkAdapters.com
Compatible Forks
The Freakynuts® system fits:
- Fox 40
- Fox Podium
- Marzocchi DH58 (latest generation)
More models are continuously being added.
Why Riders Choose Freakynuts®
✔ Designed specifically for Fox 40 forks
✔ Precision CNC machined in Germany
✔ HAAS manufactured
✔ Premium 7075 aircraft aluminium
✔ Zero play
✔ Extremely precise fit
✔ No fork modifications required
✔ Available in multiple colours
✔ Worldwide shipping
✔ USA warehouse
✔ Thousands of satisfied riders
✔ Ride your existing 15×110 Boost wheel
Ride Your Favourite Wheels Everywhere
One wheel. One adapter. Unlimited riding.
Whether you’re riding your local bike park, racing downhill, chasing KOMs or sending Rampage-sized features…
Freakynuts® delivers the strongest and most precise Fox 40 15mm adapter available.
Ride without compromise.