OZ Gass RS-A Forged Aluminium Rear Wheel – Aprilia RS 660 (2020-2026) H6305AP55

The OZ Gass RS-A is a forged aluminium rear wheel engineered for the Aprilia RS 660, bringing WorldSBK-derived construction directly to road and track use. Manufactured in Italy to OZ's exacting standards, the Gass RS-A reduces unsprung and rotating mass in a single move — sharpening steering response, improving acceleration and delivering the kind of agility that only a genuinely lightweight wheel can provide.

Key Features

• Forged aluminium construction — exceptional rigidity-to-weight ratio, built to outlast cast alternatives on road and circuit alike.
• Reduced rotating mass measurably improves handling, turn-in precision and acceleration at all speeds.
• Available in four anodised finishes: gloss black, techno black, techno gold and titanium — each a durable, corrosion-resistant surface treatment rather than paint.
• Made in Italy: manufactured under the same quality controls that supply OZ's WorldSBK programme.
• Includes high-quality bearings, aluminium angled valve stems and spacers (fitted only where required).
• Supplied with a rear sprocket carrier — note that the original Aprilia sprocket carrier is not compatible; the included carrier must be used.

Construction and Materials

OZ has long been synonymous with precision forged wheels, and the Gass RS-A upholds that heritage without compromise. The one-piece forged aluminium rim starts life as a solid billet, then undergoes a multi-stage forging process that aligns the grain structure of the metal for maximum fatigue resistance. The result is a wheel that is demonstrably stiffer than an equivalent cast design, yet significantly lighter — a combination that translates directly into lap times on track and greater rider confidence on the road. The anodised finish is integral to the alloy surface rather than applied over it, so it resists stone chips, brake-dust contamination and UV degradation over the long term.

Performance on Road and Track

Fitting the Gass RS-A to an Aprilia RS 660 addresses one of the most effective upgrades available: reducing rotating unsprung mass. Every kilogram removed from the wheel demands less energy to accelerate and decelerate, allowing the suspension to track the road surface more accurately and the chassis to respond more quickly to rider inputs. Whether you are threading through mountain passes or working through a circuit session, the improvement in agility and directional stability is tangible. The design has been developed with an ideal balance between structural stiffness and minimum weight — neither sacrificed for the other.

Fitment and Compatibility

This rear wheel is designed specifically for the Aprilia RS 660 model years 2020 to 2026. The kit includes a dedicated rear sprocket carrier; the original Aprilia sprocket carrier will not fit and must not be used. Spacers are supplied and fitted only where the installation requires them. All necessary bearings and aluminium angled valve stems are included in the box.

Specifications

• Part number: H6305AP55
• Brand: OZ
• Model: Gass RS-A
• Position: rear wheel
• Material: forged aluminium
• Finish: anodised (gloss black / techno black / techno gold / titanium)
• Fitment: Aprilia RS 660 (2020–2026)
• Origin: Made in Italy