I rang the dealers and they confirmed the main cap bearing bolt length is 65mm for my engine.
Now the main cap it self is around 53mm in length.

This means only 12-15mm goes into the block it self. The torque setting is 65NM. These are not stretch bolts.

Can only 12-15 mm of thread hold all that power.?
There are ten bolts in total

Probably! The stress is not distributed evenly across the threads the first one does most of the work. You do not give the size of the tread but if the engaged legnth is 1 x diameter then you are in the right range for the bolt snapping before pulling out.

see this

http://www.roymech.co.uk/Useful_Tables/Screws/Thread_Calcs.html

Size is M10 X 1.5 pitch X 65mm Length

so 12-15mm is > more than 10mm (M10)
Thanks

[Edited on 16/10/17 by bikecarbfred]