The 2008 and newer 4-stroke KTMs (and some earlier SX models) use a timing chain tensioner intended to develop its force using the engine oil pressure. The OEM tensioner has serious flaws
which can leave the timing chain in a slack condition, possibly causing serious engine damage.
Dirt Tricks has developed a simple, effective and failsafe replacement. The Dirt Tricks timing chain tensioner correctly captures the oil pressure, and then uses a positive mechanical ratcheting system to prevent it from collapsing. The
replacement unit will work on all newer four-strokes in 250, 400, 450, 505, 530 models using the RC4, XC4, or RF4 motor (not for the RFS motors).
Read the Installation