Valve Stem Seals VFR750FM 1991

I have been rebuilding this project bike and having rebuilt the engine and used a Vesrah top end gasket set and the valve stem seals within this set.

However on starting up it was burning oil and when throttling up more oil was burning.

I suspected oil sucking past the seals but as they are new I was puzzled.

I have already checked the valve stem diameters and the guides and they are all within tolerance. I have also done a leak down test so I know its all good there.

So I took the carbs off and while turning it over on the starter I could see oil mist getting sucked into the inlets.

Maybe I have damaged the seals when putting them on but I was also wondering, having seen different Honda part numbers for the exhaust and inlet valve stem seals if they are different diameter or material as all the Vesrah ones are one single colour.

When installing the seals should I have put tape around the valve stems???

Anyone else had an issue with valve stem seals or can offer any advice?