⟲ 360° — drag meThe facts.
| Part number | S-K2R3-APC |
|---|---|
| System type | Full exhaust system (Racing Line) |
| Header material | Stainless steel |
| Silencer shell material | Titanium |
| End cap material | Carbon fibre |
| System weight | 4.4 kg (saving 5.2 kg vs. stock 9.6 kg) |
| Peak power (with system) | 73.6 hp at 14,600 RPM (+2.2 hp vs. stock 71.4 hp) |
| Peak torque gain | +2.2 Nm at 7,000 RPM |
| Sound level (without DB-killer) | 107.5 dB at 7,250 RPM (+12.9 dB vs. stock 94.6 dB) |
| DB-killer | Included |
DescriptionThe whole story▼
The Akrapovic Racing Line full exhaust system for the Kawasaki ZX-4RR (2023–2026) is an engineering-led upgrade that delivers measurable, back-to-back gains straight from the crate. Shedding 5.2 kg over the stock system and unlocking an additional 2.2 hp and 2.2 Nm of torque, this stainless steel full system is the most complete performance exhaust solution available for the ZX-4RR platform.
Key Features
- Significant weight reduction of 5.2 kg — stock system weighs 9.6 kg; this system weighs just 4.4 kg
- Power gain of 2.2 hp, taking peak output from 71.4 hp to 73.6 hp at 14,600 RPM
- Torque improvement of 2.2 Nm at 7,000 RPM for stronger mid-range delivery
- Race-grade sound: 107.5 dB at 7,250 RPM without DB-killer (+12.9 dB over stock)
- DB-killer included for added versatility at noise-sensitive venues
- Stainless steel headers with lambda sensor connection for ECU compatibility
- Titanium slip-on silencer shell with carbon end cap — all internal metallic components also in titanium
Build Quality & Materials
Akrapovic have constructed the Racing Line around stainless steel headers that retain the lambda sensor port, ensuring the stock fuelling management system remains functional without additional mapping hardware on the day of fitment. The slip-on silencer takes the lightweight approach further: the outer shell, brackets and all internal metallic parts are titanium, while the end cap is finished in carbon fibre. This combination keeps the system at 4.4 kg total — a substantial saving that translates directly into improved power-to-weight and sharper steering response under braking and acceleration.
Performance on Track
The numbers speak plainly. Tested back to back against the standard Kawasaki system, the Racing Line delivers 73.6 hp at 14,600 RPM and an additional 2.2 Nm of torque at 7,000 RPM — gains that broaden the usable power band through the mid-range and extend the top-end rush the ZX-4RR inline-four is known for. The exhaust note rises to 107.5 dB at 7,250 RPM when the DB-killer is removed, giving the bike an unmistakable race presence in the paddock and on circuit. When regulations require a quieter note, the included DB-killer drops the output back to compliant levels without permanent modification.
Everyday Usability & Value
While the Racing Line is homologated for track and competition use only and carries no road-type approval, its real-world value is clear for any ZX-4RR owner serious about performance. The lambda sensor connection means no major wiring work on initial fitment, the DB-killer gives flexibility across different circuit noise bylaws, and the one-piece stainless-to-titanium architecture removes the maintenance headaches associated with multi-material joins. For riders who want a single, complete system that handles headers and silencer in one purchase — and delivers documented dyno results — the Racing Line represents straightforward, measurable value. Part number S-K2R3-APC.
Fitment & Compatibility
This exhaust system is designed exclusively for the following motorcycle:
- Kawasaki ZX-4RR — model years 2023, 2024, 2025, 2026
Specifications
| Property | Detail |
|---|---|
| Part number | S-K2R3-APC |
| System type | Full exhaust system (Racing Line) |
| Header material | Stainless steel |
| Silencer shell material | Titanium |
| End cap material | Carbon fibre |
| System weight | 4.4 kg (saving 5.2 kg vs. stock 9.6 kg) |
| Peak power (with system) | 73.6 hp at 14,600 RPM (+2.2 hp vs. stock) |
| Peak torque gain | +2.2 Nm at 7,000 RPM |
| Sound level (without DB-killer) | 107.5 dB at 7,250 RPM (+12.9 dB vs. stock 94.6 dB) |
| DB-killer | Included |
| Road approval | None — track and competition use only |
| Fitment | Kawasaki ZX-4RR (2023–2026) |
FitmentWhich bikes this fits▼
- Kawasaki ZX-4RR (2023–2026)
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.