PROX engine bearing - 21.4214 15 × 19 × 20 mm

Discontinued : this product is no longer made and can no longer be ordered.

Check before ordering

• Dimensions (inner × outer × width): 15 × 19 × 20 mm

PROX offers this engine bearing. The engine’s shafts run on ball or roller bearings in the cases. They carry heavy loads at high revs and eventually develop play.

What is this bearing made of?

Races and balls (or rollers) in hardened chrome steel, 100Cr6 type: a very hard steel that withstands the fatigue of millions of engine revolutions.

• Open bearing: unsealed, it is lubricated and cooled by the engine oil; clean oil is its best protection.
• C3 / C4 internal clearance: slightly more clearance than normal for a hot engine’s expansion; always refit the original clearance.
• Limit: it dislikes dust and old oil; running short of oil destroys it within minutes.

Why choose PROX?

ProX uses Koyo or NTN bearings, largely made in Japan in OEM factories, with the original internal clearance (C3 / C4).

When should you replace the bearings?

On competition bikes the main bearings are replaced at every bottom-end rebuild, at the hours recommended by the manufacturer. With the cases open, spin each bearing by hand: the slightest rough spot means it must go.

Specifications and fitting tips

• Application: Upper pin
• Made by leading Japanese OEM manufacturers
• Built to the manufacturer's specifications as a direct, lower-cost replacement for the original part

Cross-Mania tip: Heat the cases to remove and fit the bearings without forcing them, and replace the oil seals at the same time.

Also needed with this part

• 4-stroke engine oil : LIQUI MOLY 10W40 1 L · MOTUL 10W50

Compatibility

Universal part: check the dimensions before ordering.