If you have a "ticking" noise at idle, on your newer four-stroke, you need this part.
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 O.E.M. 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 uses oil pressure combined with a mechanical ratchet system to prevent collapse and avoid issues caused by a slack timing chain on the new 4-stroke motors. 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).