Replaces OEM 8990/A style ball bearing. This bearing will fit will fit all models as front & rear outer cam bearings. Note: The MoCo has redesigned the Twin Cam rear outer cam bearing from ball to a roller bearing style in 2001. This was done to help prevent failing ball bearings on, specifically, rear (=driveside) cams that are heavier loaded. This 01-up roller style bearing is a 3-piece design that is more heavy duty than the roller bearing. No other parts changed during the bearing changes. The early 99-00 style ball bearings will still fit all 99-06 models front & rear. Using front & rear ball bearings present no issues on cam driven gears.
Fits: > 99-06 Twin Cam (excl. 2006 Dyna) (NU)
Koyo, needle bearing camshaft. 'Full needle'
Koyo (former Torrington). When still present it is advised to replace the low cost OEM needle bearing in 92-99 Evolution Big Twin models marked 'INA SCE 138 USA' with a 'full needle' bearing to increase reliability. Especially important when using higher lift cams, which increases stress in the camshaft bearing. OEM replacement reference 9058, 9058A
Fits: > 58-99 Big Twin (Excl. Twin Cam) (NU)
S&S, needle bearing camshaft. 'Full needle'
When still present it is advised to replace the low cost OEM needle bearing in 92-99 Evolution Big Twin models marked 'INA SCE 138 USA' with a 'full needle' bearing to increase reliability. Especially important when using higher lift cams, which increases stress in the camshaft bearing.
Fits: > 58-99 B.T. (excl. Twin Cam) (NU)