Thank You Eric and Andy for your quick response.

I forgot to mention the bike is from the first type of the MC16(1986).

I already found out that there are two types of the MC16, where the second type has a bigger shaft in the middle of the crankshaft. So, the links to the seals Eric mentioned will not fit. The shaft in the middle of the crankshaft of the type 1 MC16 is 45mm.

The type of seal we are looking for is a FAJ8 45x68x5,5 GS, the (de)mounted brand is Ats.

The Crankshaft is already pressed apart. And ofcourse all bearings will be replaced. I think the mechanic who is restoring the engine knows what he is doing.

Kind regards,
Zurgel