Pulled from world.honda CTX1300 page..
????As a feature unique to the CTX1300, a traction beam that effectively transmits the engine's inertial force to the rear tire is set independently of the main frame, to bring out the most in the delightful throbbing feel of a V4.
This setup is very effective in enhancing the fun of operating the CTX1300, on top of its excellent controllability and stability.