This is a guide for thise looking for the crankcase breather valve. Where I have put the arrow it is about half way down at this point. The valve is within a pipe so look carefully for a pipe with a bulge! Have a feel around! The pipe has a couple of jubilee clips and can be got to without taking anything else off if you have skinny wrists! Otherwise you may want to look at taking the coolant tank off.
Hope this helps......
Hope this helps......