Hi I know it was last posted in 2014 but if it is any good I have a Vokes filter fitted to my Mk5 ,I took the filter housing apart and then stripped out the filter assembly to reveal the felt filter,which I started to clean,I then thought about a replacement paper pleated type filter so I visited a local motorcycle dealer who stocks Hi Flow filters,HF140 is the same size as the felt item and all I had to do was remove the central spring loaded bypass unit ,it all fitted back together with the new filter no problem ,this filter is a common part accross lots of Japanes bikes up to 450cc it only cost £4 ,for a couple of pounds extra they even sell brass mesh type ,this filter will I think offer better filtration than the felt item with a lot less restriction .
As I said above I hope this is of some help to someone with a Vokes filter
Regards. Colin