The QJMOTOR SRK 421 RR has officially arrived to shake up the mid-weight supersport category, blending aerodynamic engineering with high-speed styling. The SRK 421 RR fuses a screaming four-cylinder soundtrack with precision control to deliver an unprecedented thrill for those chasing the ultimate ride.
The heart of the SRK 421 RR is a 421cc inline four-cylinder, 16v DOHC engine producing 77.6ps (57kW) at 14,000rpm. Designed for linear and smooth power delivery, the engine is beginner-friendly while offering high-rev thrills for track-inspired performance. A peak torque of 39Nm is delivered at 13,000rpm, but still produces enough low-end urgency to ensure responsive delivery on city streets.
The engine also features DLC-treated valve tappets, an electroplated ceramic cylinder and a forged alloy steel camshaft. High-end components are also used from famed Japanese companies, including FCC paper-based clutch plates, NTN bearings, RIK piston rings, and Daido crankshaft bearings.
The SRK 421 RR has been crafted by the designers of some of the most acclaimed motorcycles and features original mecha-inspired styling that creates a futuristic presence. Its aerodynamic bodywork includes bold lines, geometric cuts, and a hollowed tail section that channels airflow to reduce drag. The aggressive front face is equipped with a Ram Air intake to ensure efficient combustion and enhanced power output at speed.
Other distinctive styling touches include a three-dimensional floating taillight and a race-ready rider triangle created by lowered handlebars and raised footpegs. The 16-litre fuel tank is sculpted for ergonomic support, while the 808mm seat height ensures accessibility for a wide range of riders.
The steel-aluminium composite braided frame provides high-strength rigidity and has an evenly-balanced weight distribution for handling agility. This is paired with fully adjustable upside-down telescopic forks and a rear multi-link shock absorber from Marzocchi. Premium stopping power is provided by Brembo radial four-piston calipers acting on 300mm dual front discs and a two-piston caliper operating a 240mm single rear disc, supported by a dual-channel ABS system.
The rider interface is headlined by a 7-inch TFT display
featuring a multi-language menu, smartphone connectivity, and navigation
mirroring. Riders can toggle between Normal and Sport modes to adapt throttle
response and the level of intervention from the Traction Control System (TCS)
and ABS. Sport is designed for track use, allowing slight rear wheel slip and
wheelies.
Additional premium features include a Tyre Pressure Monitoring
System (TPMS), an 18W dual-port USB (A&C) fast charger, and optional front
and rear integrated cameras.
The QJMOTOR SRK 421 RR costs £5,299 (plus on the road charges)
and is available in three colour options: Black, White or Red/Silver.
For more information and to find your nearest dealer, visit qjmotor.co.uk
