Crankshaft bolt size

[apaz]

Hey there riders.

So I'm replacing a broken bolt in the cylinder head cover and I'm working through the steps in the manual (pic provided) and I don't know what the size of the crankshaft bolt is to roatate it and line up the "T". The largest socket I have is not working and before I go out and buy, I thought I would ask everyone here. I did some searches of the forum and the net to see if I could find the info with no luck.

Please help, I'm kind of stuck at this point and would love to keep going on the job. Also another question, I'm doing the job with the engine in, how hard is rotating the crankshaft with the engine in?

I really appreciate the help.