We are trying to satisfy 100% of our customers
Our bikes are 100% safe and eco-friendly
✕
biker4-shop-icon3

Derailleur (Rear)

julio 22, 2026

Shimano Ultegra R8000 Mechanical Rear Derailleur RD-GS Medium Cage – Black

The Shimano Ultegra R8000 Mechanical Rear Derailleur RD-GS Medium Cage in Black is a high-quality rear derailleur designed for various bike types including road bikes, hybrids, cross bikes, and tandems. Made of durable aluminum, this 11-speed derailleur comes with a 2-year manufacturer warranty and is compatible with Shimano components. The set includes the rear derailleur itself, and its medium cage length ensures smooth gear changes for any cycling enthusiast. Perfect for sporty riders looking for precision and reliability in their cycling components.
julio 22, 2026

Jockey Wheels with Ceramic Bearings for Shimano 12 speed derailleurs

NOTE: THESE JOCKEY WHEELS ARE FOR 12 SPEED REAR DERAILLEURS. If you have a 10 speed rear derailleur we sell those jockey wheels under eBay item 260823214178ACER Racing presents our 13 tooth Carbon Fiber Jockey Wheels with Ceramic Ball Bearings for Shimano. The gears are made of super stiff and lightweight 7075 Aluminum and we include our World Champion ACER Racing Ceramic Nitride Pro Series ceramic ball bearings with dual seals in each jockey wheel. Lightweight removable red aluminum covers protect the ceramic ball bearings further from the elements while giving a more aggressive appearance. The ceramic bearings are not lubed as they are designed to run dry for maximum speed. Lowering your rotational mass is extremely important when racing. Reducing weight off parts that actually move or rotate such as wheels or jockey pulleys have a much greater effect on performance than removing an equivalent weight off a part that is stationary such as a lighter bicycle frame. That is the design concept and philosophy behind our carbon fiber jockey wheels. They are light enough to have a significant impact on acceleration while decreasing friction. Our ceramic bearings inside further compliment the lightweight carbon fiber design by lowering rotational mass and offering the friction free performance we have been known for since 1989. Lower your rotational mass for quicker, smoother acceleration and higher speeds with less effort with our remarkable new ceramic jockey pulleys. PRICE IS FOR TWO PIECES AS SHOWN IN PHOTO.
julio 22, 2026

SRAM GX Eagle Rear Derailleur for 12-Speed Drivetrain

The GX Eagle derailleur not only answers the drivetrain’s need for greater capacity, but it’s also the next evolution of the 1X specific SRAM X-Horizon design. Cage Lock has been moved back and out of the way protecting it from trail debris.
julio 22, 2026

Shimano Ultegra RD-6600 Rear Derailleur 10 Speed Long Cage Silver Japan 200g

Shimano Ultegra RD-6600 Rear Derailleur 10 Speed Long Cage Silver Japan 200g Shimano Ultegra RD-6600 Long cage rear derailleur in silver for road bikes. 10-speed compatible design for Shimano road drivetrains and STI shifters. Standard hanger mount with aluminum body, steel hardware and composite pulley wheels. Model marking: RD-6600. Made in Japan. Weight: 200 g. Used Shimano Ultegra RD-6600 10-speed rear derailleur. Body has many scratches, scuffs and finish wear, especially on the upper mounting pivot. Pivot turns ok. Pulleys show noticeable wear with nicks and burrs along the teeth and accumulated grime around the bearings.