Just leaving upside down for 60-min should be fine to drain oil from top-end. Be sure to check oil-level in crankcase after righting and adjust as necessary.

Ok so turn upside down leave it for the day then turn right way up , check the oil turn give a couple cranks , then drain oil

Sounds good. :)

Just a quick one I got a new battery in bike but it’s now going to be sitting a few weeks will it be dead by the time I need it or ??

Is it fully charged? If so, it’ll be fine. Best to connect tender chargee.

Brand new battery, also when I flip this engine should the piston position be bottom dead centre

Not possible for all pistons to be TDC or BDC. Shouldn't matter, you'll just want to drain everything above piston. Some pistons will be up, some down.

Ok so I still got to strip my bike so I got a bout a week maybe I flip it then crank, flip it again then crank just while it’s sitting there over the next week or so then drain defore I put it in or drain it once it’s in

Okay so engine is hanging upside down I made a video explaining what I’ve done if it’s correct ???

Yup, looks good! Drain bottom and refill and should be ready to install! Good job! :)