The facts.
| Brand | STM |
|---|---|
| Part number | FDU-S040 |
| Type | Slipper clutch (anti-hopping clutch) |
| Fitment | Ducati Panigale 899 (2013–2016) |
| Slipper mechanism | Patented ball-ramp system |
| Spring type | Diaphragm spring |
| Weight saving | Approximately 0.7–0.8 kg reduction in rotating mass vs. stock |
DescriptionThe whole story▼
For riders who want a more composed, confidence-inspiring Panigale 899 on both road and track, the STM slipper clutch FDU-S040 is one of the most worthwhile upgrades available. It eliminates the rear-wheel hop and engine over-rev that can unsettle the 899 under hard downshifts, making braking zones safer and more consistent without demanding any change in riding style.
Key Features
- Prevents engine over-rev on downshifts, maintaining stable, predictable power delivery through the drivetrain
- Reduces rear-wheel hop for improved traction and more precise control when trail-braking
- Minimises the trigger impulse of a highside, significantly improving safety on track and spirited road rides
- Allows controlled rear-wheel slide for optimised handling balance and increased rider confidence
- Improved clutch engagement feel in corners prevents the front end from tucking under deceleration
- Diaphragm spring eliminates pressure-plate judder for a smoother, cleaner lever release every time
- Patented ball-ramp mechanism governs the slipper function with precision at high engine speeds
- Significant weight saving of approximately 0.7–0.8 kg through a reduction in rotating mass, sharpening overall throttle response and engine dynamics
Build Quality and Technology
STM has developed the FDU-S040 around a patented ball-ramp system that progressively limits back-torque during downshifts. Unlike simpler cam-ramp designs, the ball-ramp geometry delivers a consistent, repeatable release point regardless of engine speed, giving the rider a predictable sensation at the lever. The diaphragm spring replaces a conventional coil-spring stack, removing pressure-plate flutter under rapid throttle transitions and producing the smooth clutch action that STM slipper clutches are known for throughout the paddock.
The reduction in rotating mass — approximately 0.7 to 0.8 kg compared to the stock unit — is not just a number on paper. On a motorcycle as responsive as the Panigale 899, lighter rotating inertia translates directly into crisper throttle pick-up and a more agile feel mid-corner. This makes the FDU-S040 a genuinely useful everyday upgrade as much as a track-day tool, improving the 899's character at any pace.
Road and Track Use
The STM FDU-S040 is equally at home on a technical mountain road as it is in a race paddock. On the road, the slipper function takes the stress out of hurried downshifts, whether through an unfamiliar set of bends or in stop-start traffic where lever use is frequent. On track, it provides the consistent back-torque limitation that allows riders to exploit the 899's braking performance fully, without worrying about a snapping rear end upsetting the entry phase. The improved clutch engagement feel through corners is a particularly notable benefit: the tendency of dry-clutch Ducatis to lurch on partial engagement is substantially reduced, allowing smoother, more measured drive out of slow corners.
Fitment and Compatibility
This clutch is a direct-fit replacement unit for the following model:
- Ducati Panigale 899 – model years 2013, 2014, 2015, 2016
Specifications
| Specification | Detail |
|---|---|
| Brand | STM |
| Part number | FDU-S040 |
| Type | Slipper clutch (anti-hopping clutch) |
| Fitment | Ducati Panigale 899 (2013–2016) |
| Slipper mechanism | Patented ball-ramp system |
| Spring type | Diaphragm spring |
| Weight saving | Approximately 0.7–0.8 kg reduction in rotating mass vs. stock |
FitmentWhich bikes this fits▼
- Ducati Panigale 899 (2013–2016)
Questions, one topic at a time.
Get the real shipping cost for this item to your address — the same rates as checkout.
Choose a destination and hit Estimate — we fetch the live rates for this item.
We’re based in Germany. Standard delivery goes by DHL and national postal services and takes about 2–5 days within Germany, 1–2 weeks within the EU and 2–6 weeks outside the EU. Need it sooner? Express delivery reaches most of the world within a few days — just choose it at checkout where available.
Your exact shipping cost is calculated by destination and weight and shown at checkout before you pay — no hidden fees. Express delivery is selectable at checkout where available.
Yes, we ship to over 130 countries. Prices, taxes and delivery times for your destination are calculated automatically at checkout.
Within the EU, no — our prices already include all duties and EU VAT. For deliveries outside the EU (e.g. Switzerland, the UK or the USA), your order may be subject to import duties and taxes set by your country. These are collected by the carrier when your parcel arrives, aren’t included in our prices, and are outside our control.
As soon as your parcel ships we email you a tracking link, so you can follow it all the way to your door.
On out-of-stock items you can request a delivery time or leave your email to be notified the moment it returns — just use the notification box on the product.
You have the right to cancel within 14 days of receiving your order. Register your return by email first; once it’s approved you have a further 14 days to send the goods back. Items should be unused and in their original packaging.
Register your return by email with your order number before sending anything back, and we’ll send you the return instructions. Please note: returns that aren’t registered in advance can’t be accepted.
The quickest way is to place a new order for the size you need and register a return for the original by email — just let us know it’s an exchange.
We’re sorry — that shouldn’t happen. Contact us with your order number and a photo as soon as you can, and we’ll arrange a replacement or refund right away. Faulty goods are always covered by your statutory warranty.
Refunds go back to your original payment method, usually within 3–5 working days of your return reaching our warehouse.
PayPal, all major credit and debit cards (Visa, Mastercard, American Express), Klarna (pay later and instalments), Apple Pay, Google Pay and more — all processed securely via PayPal and Mollie.
Yes. Choose Klarna at checkout to split your purchase into flexible monthly installments.
Your payment is taken when you place your order. If you choose Klarna, you pay later according to Klarna’s terms.
Every payment runs over an SSL-encrypted connection through certified providers. We never see or store your full card details.
If your order hasn’t shipped yet, contact us as soon as possible and we’ll do our best to change or cancel it.
No — you can check out as a guest. An account simply lets you track orders and reorder faster.
For customers in the EU, prices are shown including your country’s local VAT. For customers outside the EU, prices are shown without VAT — instead, your country’s import taxes and duties may apply on delivery (see the customs question).
Yes. Your invoice is attached to your order confirmation email and is also available in your account.
Yes. We’re an authorised dealer, so every product is 100% original and comes with the full manufacturer warranty.
Yes. Everything we sell is genuine and comes with the manufacturer’s warranty, on top of your statutory rights. Keep your invoice as proof of purchase and contact us if you ever need to make a claim — we’ll help you through it.
Our team is happy to help. Use the contact button below and we’ll personally help you choose the right gear or part.
Measure your head circumference about one centimetre above your eyebrows and compare it with the size chart on this page. Between sizes? Choose the smaller one — the padding beds in with use.
Yes — it’s tested and approved to the current ECE 22.06 standard and road-legal across the EU.
Most of our touring and sport helmets are Pinlock-ready and many include the insert. Check the ‘What’s in the box’ section on this page for this model.
Yes — the cheek pads are channelled so the arms of your glasses slide in comfortably.
Take out the washable lining and hand-wash it in lukewarm water. Clean the shell and visor with a soft cloth and water only — never solvents.
Our team will personally help you choose the right gear or part — around 24h for a reply.