I just have a few motorcycles in my accumulations and only one Maisto. It is a 1999 Heritage Springer in red and is 1:18 scale. You have probably looked yours over too but to me they seem well engineered in assembly. And most parts just sort of snap into place but look to fragile to manually unsnap.
Mine looks like it has an access tube with an insert tab you could drill out to split the engine apart into its two halves from the bottom.
I can also see a 'glued' post under the fuel tank into the frame. With the engine out you may be able to drill it out as well,but its a least a 1/4 inch in diameter.
The saddle bag detail on this one is just increadable! Been awhile since I looked at it and it was unsealed so I took it out of the box this time.