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Mainshaft ball bearing

This bearing has been used from 1952 to 1984.
Part number 9025 from 1952 to 1956, 9025A from 1977 to 1984.

Available as a standard industrial bearing. NTN 6207-ZZ, Fafnir 207KDD

This bearing has metal shields, not rubber seals. The metal shield keeps excess oil out of the bearing, which would make it run hot.

The metal shield also prevents the kickstart gear spriral spring from getting into the bearing cage and doing damage.

Bearing with rubber seals are often not pre-lubricated.

Sportster_Trap-doorsThe Iron Sportster trap door assembly holds the mainshaft, countershaft, and shifter mechanism.

Iron Sportster mainshaft roller bearing 9025A
Bottom of first column move down to the left
Sportster_9025A_Mainshaft-roller-bearing_SKF-6207-ZZ.jpgSKF 6207-ZZ

Sportster_9025A_Mainshaft-roller-bearing_Fafnir-207KDD.jpgFafnir 207KDD
move up a little to the right This is the end.