Lower crank case bolts when tight crank won't turn

[Fazerider]

Are all the bearings in their original positions, or have they got muddled up?
Like the camshaft bearing, they are machined in situ to ensure alignment. Get them swapped around and some will be too loose and some too tight.
Nipping bolts up by hand is fine in non-critical areas, but it’s important to get it right for the crankcase and major engine bolts.
Use a torque wrench.