Sorry I have been busy today but this thread did prompt me to contact the same business that did my Moto Guzzi cylinder heads, after some discussion there is a possibility oversized valves might reclaim the valve seat (They are a Kibblewhite agent also) I will take the head down to them next week to evaluate but given its cost I am very reluctant to let it out of my sight. # This was only a heads up to anyone else, I would imagine that both my FA cylinder head # 170 and Gortnippers # 172 were not only in the same batch but probably sat beside each other at manufacture at some point. I bought the head in November 2016. Obviously at $3350 it is not a cheap purchase so I asked the seller to check it over. When I informed that person one valve seat was damaged and the 3/8 threads were very average I was told .... Thanks for the feedback ie fobbed off. The head should have been replaced immediately with one fit for purpose. When I mentioned this damage in a thread right here on Access Norton long ago Ken actually replied in the thread basically saying FA heads are perfect. I was naive enough to think he would contact me promptly, I have never been angry about it just utter disappointment. As I have said in the past, a great effort by him (Ken) but at the end of the day if you sell something for money it better be fit for purpose, especially when it cost over $3000 bare. I guess I just got one that slipped through the cracks but do you think he has contacted me ever, including after reading this thread, of course not. No warranty, doesn't care. Just for anyone who just doesn't understand what I have posted and no I was not grateful and the picture is very complimentary. Which comes back to square one, if you are looking at buying a FA cylinder head ( as per the thread topic) around # 170 check the valve seats for damage.