yea this is a newer VM design I think. One thing I've learned is that a VM20 is not necessarily the same as a VM20.
I mean like with SHA's and PHBG's etc, the parts and designs remain pretty unchanged, but with VM's they made shitloads of custom fits for specific production models, some take 5mm round jets, 6mm round jets, hex jets, it gets crazy. Different mounts, diameters of filters whatever. some are identical externally but have different length needles or dont fit the same parts etc. it's nuts.
anyway, the mikuni manuals are pretty useful to figure out what's up in there. or just set it and forget it cuz vm. they're real easy to get tuned.
http://www.mikuni.com/pdf/vmmanual.pdf