Hi mdr,
Thank you for your comments. I do hope people follow this thread for what it is, ie disproving a rumour. Anyone with a different experience, do please come forward. The chap who stated this view with certainty may have an agenda, I like to get a wider view. Out of interest, I have fitted temp stickers to my unit and will monitor how hot the cylinder head and crankcase get during usual operation, and will post results for people's interest. Please, do post if you have a view.