Internal cable routing turns a five-minute job into an hour of fishing around inside the frame with magnets, flashlights, and bad language. The Park Tool 346.2 Internal Cable Routing Guide eliminates that struggle with a flexible nylon-coated steel cable that snakes through frame tubes, bottom bracket shells, and chainstays without snagging on internal ribs or weld flash. Once the guide is in place, the included barbed adapter tip attaches to your housing, brake hose, or Di2 wire and pulls the new cable through the frame in one clean motion.

The guide measures roughly 1.5 meters in length, which covers full top-tube-to-rear-derailleur routing on essentially any frame size. The nylon coating slides past internal frame features that would catch a bare steel cable, and the coating also keeps the guide from marring paint or carbon at the entry and exit ports. The cable is stiff enough to push through a tube without folding back on itself, but flexible enough to navigate the bends at bottom bracket shells and chainstay junctions.

The barbed adapter is the key to the system. It threads onto the end of the routing cable and accepts the leading edge of brake housing, derailleur housing, hydraulic hose, or electronic wire. The barbs grip the inner diameter of housing and hoses without crushing them, so the new line follows the guide cable exactly as it gets pulled back through the frame. For Di2 and AXS wires, the adapter pairs with the connector end to drag the wire through without stressing the terminal.... Read More