Klug built a very tasty 1200 Egli, (beautiful looking exhaust system and alloy tank) your bike may have originally been the donor, hence the miss matched engine/chassis number
I don't see the frame number, (have I missed something), where is it located (headstock or gearbox mount) and what is the full number, starting with L and ending with a *?
the straps on your picture of the bike on the trailer are ineffective, and will not stop the bike leaning to the left or right, the rear ones are better then the front which is doing no good, none of the straps incorporates a clutch or strangle if you prefer. Agree with Red's comments on the frame mods, but what he sees is not what it purports to be., Maybe the original frame number was stamped on the Egli so as to retain the original regsitsration, and yours have been err attended to?
CLEM
magnifier at the ready