Chimera Upgraded Cam Chain Tensioner Button Grom

The Chimera Upgraded Cam Chain Tensioner Button is a targeted engine reliability upgrade designed for the Honda Grom MSX 125. In the stock engine, a small rubber button serves as the contact point between the cam chain tensioner arm and the timing chain guide. Over time and mileage, this OEM rubber component compresses, deforms, and wears down, gradually reducing the tension on the cam chain. As slack develops in the timing chain, it can lead to imprecise valve timing, audible chain rattle, and in severe cases, catastrophic engine damage if the chain skips teeth or contacts other internal components.

Chimera's replacement button is engineered from more durable material to resist the wear and deformation that plagues the factory part. This is an especially important upgrade for Grom owners who have installed big bore kits (BBK), as the increased engine output places greater stress on the entire timing chain system. Installation requires removing the flywheel to access the tensioner button's location behind it, which is why professional installation is recommended unless the rider has experience with this level of engine work. Once installed, the upgraded button maintains consistent pressure on the cam chain guide, preserving proper timing chain tension and protecting the engine's valve train from the premature wear and potential failure associated with the degraded OEM component.