Keeping the valve clearances within specified tolerances will help maintain full performance, as well as eliminating that irritating "tappet rattle". There are no tappets on this engine, but you know what we mean!
Other shim sizes you may wish to consider:
Add as many components as you wish to the same shopping cart, new valve stem seals 33M1211900 for example, and still only pay the same single fixed price shipping cost.
Pro-workshop gasket sealant 08C70K0234M - easy to use with excellent results.
This component may have other, sometimes unrelated applications within the Yamaha model range, so please always check by the part-number rather than the description prior to ordering.