Cojinete de bolas suelto para fabricación de ruedas, grado 25 7/32"

The Wheels Manufacturing Loose Ball Bearing - Grade 25 7/32" is a precision replacement bearing for cup-and-cone hubs that call for this less-common size. At 7/32" (5.556mm) in diameter, it's the correct spec for Campagnolo Record front hubs and certain other high-end hub designs — not the size you'll find in most cup-and-cone hubs, but exactly what you need when you do. Each ball is manufactured from AISI 52100 chrome steel and held to Grade 25 tolerance standards (ABMA Standard 10 / ISO 3290), which requires roundness within 25 millionths of an inch and limits lot-to-lot diameter variation to 50 millionths of an inch.

That consistency matters more than it might seem. In a cup-and-cone bearing, undersized or out-of-round balls create uneven load distribution that accelerates wear on the cups and cones themselves — components that are far more expensive to replace than the bearings. Using correctly graded balls during a service keeps the bearing geometry correct and extends the life of the entire hub assembly. Wheels Manufacturing has been producing precision bicycle components from their Louisville, Colorado facility since 1988. The bearings are sold individually, making it straightforward to replace exactly as many as you need — a typical front hub service requires nine balls per side.

Specs at a Glance

• Diameter: 7/32" (5.556mm)
• Grade: 25 (ABMA Standard 10 / ISO 3290)
• Material: AISI 52100 chrome steel
• Roundness tolerance: ±25 millionths of an inch
• Sold: individually
• SKU: BALL-10B