Kyosho Optima 20pcs Ball Bearing Kit for Service - JR-CBR-KS-007 by Jazrider  [JR-CBR-KS-007]

Service-oriented 20-piece bearing kit

This 20pcs bearing kit is an aftermarket replacement pack from Jazrider for Kyosho Optima applications, aimed at RC drivetrain and steering parts. The assortment covers the frequent bearing sizes used on compact touring and small off-road Kyosho models so a single purchase supports multiple service tasks.

The bearings come sorted by dimension and are metal shielded to offer straightforward fitting and basic protection against light debris. The counts reflect typical wear points to minimise multiple purchases during normal upkeep.

• 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

Fitting tips: remove old bearings when you detect play or rough rotation, degrease and clean bores before pressing new bearings in, and use a press or a driver on the outer race only to avoid inner-race damage. After motor-bearing work, recheck gear mesh and shaft runout to ensure smooth operation. Metal shields help with cleanliness but do not equal sealed constructions for heavy contamination environments.

Tuning note: replacing worn bearings with low-friction options lowers drivetrain drag and can stabilise throttle response and steering precision, especially on high-revving setups and closely spaced gear ratios. Treat this set as a maintenance kit; select dedicated competition bearings if you need lower drag or sealed lubrication.