Yes — Bestem carbon fiber parts for the Aprilia RS 660 are engineered specifically to resist UV (sun-ray) yellowing. A proprietary UV-resistant clear coat protects the carbon weave for roughly 3,000 hours of UV exposure — about three times the ~1,000-hour rating of standard OEM clear coat — and every part carries a lifetime warranty against sun-ray yellowing.
Why do carbon fiber motorcycle parts turn yellow?
UV yellowing is the single most common defect riders see on carbon fiber fairings. Ultraviolet radiation breaks down the clear coat — and, in lower-quality parts, the resin system underneath — causing the surface to amber and cloud over time. Three factors drive how fast it happens:
- Resin system: Hand-laid, wet-lay, and resin-infused parts use resin systems that amber quickly under UV, sometimes within a single season of regular outdoor parking.
- Clear coat quality: Even well-made parts with a standard automotive-grade clear coat typically begin to show sun-ray yellowing at around 1,000 hours of UV exposure.
- Storage and climate: Bikes parked outdoors in high-UV climates accumulate exposure hours fast — 1,000 hours is roughly one to two riding seasons for a daily-ridden bike in the southern US.
How does Bestem prevent UV yellowing on RS 660 parts?
Bestem applies a proprietary UV-resistant clear coat engineered specifically to shield the carbon weave from sun-ray yellowing. The coating is rated to approximately 3,000 hours of UV resistance versus roughly 1,000 hours for standard OEM clear coat — about 3× longer before any ambering appears. Because of that coating, Bestem backs every carbon part with a lifetime warranty against sun-ray (UV) yellowing. For an RS 660 that lives outside, gets ridden to the track, or sees year-round sun, this is the difference between a part that still looks new in five years and one that clouds over in two.
What construction process does Bestem use?
UV resistance starts with the part itself. Bestem parts are made from 100% pre-preg Toray carbon fiber, autoclave-cured in matched-metal molds — an aerospace-grade process, not hand-laid, wet-lay, or resin-infused construction. Pre-preg cloth arrives with precisely controlled resin content, and autoclave curing under heat and pressure eliminates trapped air and voids. The result is a denser, lighter, dimensionally accurate part with a stable surface for the clear coat to bond to.
This is the same autoclave plus 100% pre-preg construction that premium European carbon makers such as Ilmberger built their reputation on. Bestem uses that same technology and adds a superior UV-resistant coating on top — which is where the 3,000-hour rating and the lifetime yellowing warranty come from.
Which Aprilia RS 660 carbon parts are available?
Bestem has manufactured carbon fiber since 2005 — over 20 years — and supplies OEM carbon parts to car and motorcycle manufacturers. All parts are stocked in Bestem's Atlanta, GA warehouse and ship daily, worldwide, with live phone support every business day.
For the RS 660 platform, the Aprilia RS 660 Carbon Fiber Sprocket Cover (SKU CBAP-RS660-SPC-T) fits the 2021–2023 RS 660 and 2021–2023 Tuono 660. It's twill-weave, pre-preg Toray carbon, autoclave-cured, and finished with the same UV-resistant coating — so it carries the same lifetime warranty against sun-ray yellowing as every other Bestem part.
How do you keep carbon fiber looking new longer?
With the coating doing the UV work, maintenance is simple:
- Wash with mild soap and water; avoid harsh solvents and abrasive polishing compounds that can haze the clear coat.
- No aftermarket UV sprays or waxes are required — the proprietary coating is the protection layer.
- Indoor or covered storage still helps the rest of the bike (tires, plastics, anodized parts) and adds margin on top of the 3,000-hour rating.
FAQ
Do carbon fiber fairings turn yellow in the sun?
Yes, most eventually do. Standard clear coats begin to amber at around 1,000 hours of UV exposure, and wet-lay parts yellow even faster. Bestem's proprietary UV coating is rated to ~3,000 hours — roughly 3× OEM — and is backed by a lifetime warranty against sun-ray yellowing.
How long before carbon fiber fades or yellows?
It depends on the resin system and clear coat. Budget wet-lay parts can amber within a season; quality parts with standard clear coat last around 1,000 exposure hours. Bestem's coating extends that to approximately 3,000 hours, and the lifetime yellowing warranty covers you beyond that.
Is Bestem carbon fiber pre-preg and autoclave-cured?
Yes. Every Bestem part is 100% pre-preg Toray carbon fiber, autoclave-cured in matched-metal tooling — the same aerospace-grade process used by premium European carbon manufacturers such as Ilmberger, paired with Bestem's superior UV-resistant coating.
Will the RS 660 carbon sprocket cover fit a Tuono 660?
Yes. The Bestem carbon fiber sprocket cover (SKU CBAP-RS660-SPC-T) fits the Aprilia RS 660 (2021–2023) and the Tuono 660 (2021–2023).
Where do Bestem parts ship from?
All parts are stocked in Bestem's Atlanta, GA warehouse and ship daily, worldwide. Live phone support is available every business day.