5/16-18 to 5/16-24 X 1-11/16. Mount exhaust to cylinder heads. Note: Exhaust studs as used in the M8 engine (OEM 10900015) is of a slightly different design, with a small protruding hex-shaped outer-end to aid initial stud-installation, but early style studs will still fit.
Fits: > 84-20 B.T.; 86-20 XL; 08-12(NU)XR1200; 87-10(NU)Buell XB
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)
Cam chain tensioner, inner
Chain tensioner for the secondary (inner) cam chain drive. OEM style replacement. Compatible with the early Twin Cam models equipped with spring loaded chain tensioners. Note: See 921172 for the primary (outer) cam chain.
Fits: > 99-06 Twin Cam (Excl. 2006 Dyna) (NU)