by Warkton Tornado No.1 » Tue Aug 18, 2020 8:35 pm
Hmmm.
There is a knack, but the design by Innocenti with only two M7 fixings is already a compromise IMHO. For that reason & because I prefer to match ports (despite any recent opinions questioning the worth) I think the engine is best dropped, even if the cables etc are left connected. In all instances I use solid copper gaskets to make a leakproof joint with bathroom silicone & to use as a means of matching. Scooter Restorations used to sell them, so I'm not the only belt & braces nutter.....
However, seeing as you asked, the 'U' bend can be fitted in situ by removing the spark plug along with the M8 & two M5 fasteners, allowing the head cowling to float about, or, in some instances, be removed altogether.
This allows far better access to the fastenings & more 'purchase' upon the nuts whilst tightening. Copaslip type grease is mandatory.
To make the task even easier, long M6 nuts which are only 10 mm AF (Toolstation etc) tapped through with an M7 tap will allow even better purchase & if you want an A1 job, cross drill them for lock wire & join them together. Similarly, this can be applied to the inlet manifold fixing if you want bomb proof.