Kyosho Optima Ball Bearing Set 20pcs by JAZRIDER JR-CBR-KS-007  [JR-CBR-KS-007]

Compact bearing kit for RC use

This 20pcs bearing kit is an aftermarket replacement pack produced by JAZRIDER for Kyosho Optima applications, intended for RC-scale drivetrain and steering components. The set groups common sizes used on small touring and off-road Kyosho models so you can refresh wheel hubs, motor shafts, idlers and suspension pivots with a single kit.

Kit contents are organized by size, supplied as metal shielded bearings for straightforward installation and basic contamination resistance. The included counts match common service points to reduce the need to buy individual bearings during routine maintenance.

• 3 x 6 x 2.5 mm — 2 pcs
• 4 x 8 x 3 mm — 2 pcs
• 5 x 10 x 4 mm — 10 pcs
• 10 x 15 x 4 mm — 4 pcs

Installation notes: replace worn bearings when play or rough rotation appears, clean housings before fitting, and use the correct press tools or gently tap with a drift sized to the outer race to avoid damage. For motor and pinion interfaces confirm internal clearance and runout after installation to maintain smooth gear mesh. The metal shields simplify maintenance but are not a substitute for full-seal bearings in wet or muddy conditions.

Role in tuning: swapping tired bearings for low-friction units reduces drivetrain drag and can give more consistent throttle response and steering feedback, particularly on higher-revving motors and tightly geared setups. Use this kit as a service pack rather than a high-performance upgrade; for low-resistance or sealed-lubricant options, choose purpose-made competition bearings.