Superb bike and should have been well maintained.
There are very few weak spots on the ST1100.
Keep the tyre pressures at 36/42 as you will notice the handling when they are a few pounds low.
Check the swinging arm as they can rot. I've hammerited and undersealed mine.
The brake calipers have a tendency to get very dirty and 'sluggish'. I strip mine down (no need to bleed, just push out the pistons, clean, grease and push back in) at least once a year.
There's a 14mm bolt holding the back of the rear caliper/swinging arm that needs to be kept copperg greased otherwise it can be a bugger to get out - a ratchet spanner also helps.
The biggest weak spot tends to be the rider underestimating the weight
Low speed manouvering
will catch you out sooner or later - let it go down and step off, you'll hurt yourself if you try to keep it upright!
All Pan riders have done it
The original wiring loom is unchanged, all they do is add an extra bit for the whistles and bells.
Don't know about single seat conversion.
A tool kit with spanner set, allen keys and screw drivers should be all you need.
Enjoy
