The Desmoquattro engines used everything from 34mm to 40mm except 35mm and 38mm. I don't know about the Testastretta engines.
Thanks Derek, I think I have been given the answer by a mechanic friend. Apparently back in the day it was not unknown for a competition engine with 36mm valves to have the inlet opened out to 38mm. It remains to be seen if either of the 748RS engines I collected yesterday have had this modification but it would explain why the box of spares that came with them included 55 off 38mm valves made by the specialist valve maker, Zanzi in Italy. Andy
Hmmm. Might be interested in a set if spares are up for grabs. I've got 37s in at the moment but if it goes pop I don't know where I'd get replacements from now.
@1037sps, I'm waiting on a reply from Zanzi to confirm what bike they were made for and from what material. Once I'm confident I wouldn't be selling a pig in a poke, yes happy to make some available if it will help. Andy
Had a chat with a friend this afternoon and he reckons Zanzi won't reply to my query because I'm not Trade. Had the same issue with Gates when I asked about 19mm wide belts for my RS engine. Sounds like a job for the apprentice inspector to compare an original with the Zanzi to confirm the diameter is the only difference. I'll be in touch. Andy
