Engine cooling systems are only as good as their sum total of parts, radiator, hose clips, water hose, even corroding fasteners - if in doubt simply replace the old degraded parts with new components. It will be less expensive than the damage caused to the engine by overheating!
Other parts you may wish to consider:
Essential part for circulating and containing the engine coolant. Specify new hose clips 9045038040 and fasteners 9502606020 9502606030 at the same time and complete the job to a professional standard. Please note; this component may have other applications in the Yamaha model range.