It depends a lot on how you drive, the cvh engine having a alloy head will have steel inserts in it anyway, often these are adequate if using normally, but if ragging it I would get the head off and make sure/get coneverted to decent lead free seats, not expensive.
As yours is a carb model, it will have the 32DFT carb, good little carb it is.
What running probs are you having, they did have a bit of an appetite for the accelerator pump diaphragms, but that apart very good units.
Nearly forgot PICCIES please!!
tabetha