When overhauling the cylinder-head, replacing as many of the wear items as possible will simplify the re-assembly and subsequent adjustments required to set up the valve gear correctly. The most vital items include valve guides, valves, stem seals, collets and valve springs.
Also pay close attention to the camshaft drive chain, tensioners, guides, rockers and the camshaft itself. Make sure the lobes are not worn, damaged or pitted?
Other related items you may wish to consider; check that you order the correct quantity of parts:
4G01113311
5VKE110102
9561708618
5VK1118100
9361216X00
5VKE118500
5VKE118510
5VKE118600
5VKE118610
5VK1211100
5VK1212100
5VK1211300
3YF1211600
3YF1211701
5VKE215100
5VK1215100
5VKE216100
5VK1216100
5VK1214600
5BP1215901
5VKE217020
9330607209
5VK1228400
5VK1229000
5VK1228001
5VKE111F00
9502206012
9459157126
5VKE223100
5VKE224100
9011906X05
9011906X09
5VKE221000
Add as many new parts to the same shopping cart as you wish, new O-rings 9321078X00 valve stem seals 5H01211900 & valve retention cotters 4G01211800 for example, and still only pay the same single fixed price shipping cost. Important! Please be aware that this component will have other applications within the Yamaha model range, so check the part-numbers you order are correct for your model and application. Pro-workshop gasket sealant 08CRAHLG120G - easy to apply with professional results.