Quote from ernie8 on 19.06.20 at 09:15:45:Hi Borderman,
I don't have spares, sorry for that. But - the plug on the TR1 chain case for inspection review has the same size. The bolt is also used on XS360 / XS400 from 1977 to 1980 cylinder head as Valve covers. Maybe this helps.
Jürgen
Hi Juergen many thanks for the reply I have the chain case and did not intend to put it back on. Sometimes what your looking for is right in front of you :thumb