The Dirt Tricks Timing Chain Tensioner resolves issues with a slack timing chain on the new 4-stroke motors. The 2008 and newer four-strokes use a timing chain tensioning device intended to develop its force using the engine oil pressure hydraulically. The OEM components have serious flaws, which can leave the timing chain in a slack condition. This can have disastrous consequences. The Founder of Dirt Tricks developed our timing chain tensioner as a simple, effective, and fail-safe replacement for the OEM tensioner. It correctly captures the oil pressure and uses a positive mechanical ratcheting system to prevent it from collapsing. If you have a "ticking" noise at idle, on your newer 4-stroke, you need this part.