How to connect the internal wiring of a carbon fiber frame

Use guide cables, dummy housings, and careful planning to route internal wiring safely through a carbon fiber frame.

Step 1: Prepare Your Frame and Tools

Before starting, ensure the frame is clean and free of debris to prevent friction or damage to cables and wiring . Gather the necessary tools: high-quality cables, housing, cable cutters, hex wrenches, a pick tool, and optionally a magnetic routing kit or guide cables . For hydraulic lines or electronic wires, consider using a dummy housing or liner to guide the actual cable through tight internal paths .

Step 2: Plan Cable Paths

Map out the entry and exit points for each cable or wire. Identify whether your frame uses full housing, interrupted housing, or sleeved routing . Avoid sharp bends that could increase friction or wear. Decide the order of installation, typically starting with the rear derailleur or brake lines, as these often require access through the bottom bracket or chainstay .

Step 3: Use Guide Cables or Dummy Housing

Insert a guide cable or dummy housing through the frame first. This acts as a path for the actual cable or wire . For hydraulic lines, tools like SRAM's threaded guide can attach the hose to the dummy housing, allowing smooth pulling while preventing fluid loss . Magnetic routing kits can also help maneuver cables through complex internal channels .

Step 4: Thread the Actual Cable

Once the guide is in place, attach the real cable or wire to the guide and carefully pull it through the frame. Ensure the cable is not pinched, kinked, or twisted during this process . For interrupted housing, measure and cut the housing first, then use a liner to guide the cable through each segment .

Step 5: Secure and Adjust

After routing, secure cables with internal clips or cable ties to prevent movement . Adjust tension for smooth operation of derailleurs and brakes. Test gear shifting and braking performance, making fine adjustments as needed . For hydraulic lines, check for proper fluid flow and absence of kinks.

Step 6: Final Inspection

Inspect all routing paths to ensure cables are fully seated, free of friction points, and properly aligned. Confirm that the frame's internal routing does not interfere with other components like the bottom bracket, headset, or suspension pivots . By following these steps and using the right tools, you can achieve a clean, efficient, and safe internal wiring setup in your carbon fiber frame, enhancing both performance and aesthetics.