Customer Service (503) 832-7336
The Only Place For People Who Ride



Couldn't load pickup availability
Free standard shipping on orders over $149
We ship to the lower 48 United States. Orders over $149 ship free; a flat rate applies under $149. Estimated delivery dates are shown at checkout based on item availability and the shipping option you choose.
We text or call to confirm sizing & fitment before we ship.
Every Factory SuperBike order includes a free expert check from real riders. Before we ship helmets and gear, we text or call to confirm your size and fit; for parts, we verify fitment to your bike. This is why we don't have to guess and you don't have to gamble.
Helmet & gear orders: reply to our text to confirm and your order ships, typically same day. No reply within 48 hours and we'll call you. Questions now? Call or text (503) 832-7336.
The Akrapovic Racing Line is a complete 4-into-2-into-1 exhaust system with a carbon fibre muffler for the 2023-2026 Kawasaki Ninja ZX-4R and ZX-4RR.
The ZX-4R is an inline four of 399 cc that revs past 15,000 rpm — a genuinely unusual machine in a market of parallel twins, and one that exists because Kawasaki wanted to build it rather than because the segment demanded it.
An engine like that lives on exhaust flow. Four small cylinders spinning that fast move a lot of gas for the displacement, and the stock system is sized for noise compliance rather than for what the motor wants. A full 4-2-1 is the single most effective change available to it.
Racing Line means a complete system built for performance rather than type approval, with a carbon fibre muffler sleeve.
Closed-course competition use only. This system does not meet emissions requirements for street or highway use.
Fits the 2023-2026 Kawasaki Ninja ZX-4R and ZX-4RR. The same part number is also listed for the Ninja ZX-25R sold in other markets. An ECU flash is recommended for correct fuelling.
Thanks for subscribing!
This email has been registered!
| Product | SKU | Description | Collection | Availability | Product type | Other details |
|---|