Renewing the cam-chain will sharpen up the valve timing and help restore lost performance.
We do strongly urge the replacement of all the other elements that make up this assembly, especially the cam chain guide, tensioner (possibly the camshafts them selves if wear is evident on the lobes) which also contribute to accurate valve timing by helping maintain the tension and accurate tracking of the cam chain itself.
Related items you may wish to consider:
Long term durability and accurate valve timing - this Japanese engineered part will deliver on both counts. Don't forget to order all the gaskets, seals and new fasteners required in one economical shipment. Please be aware that this component may have other applications within the Yamaha model range; so do check the part-numbers ordered are correct for your model.