It has taken since last October for the Ace Cafe on London's North Circular Road to get back to me. Here is the text of part of their e-mail [I had suggested 19 May]: "Thank you for your email unfortunately Saturday 19th May has been booked for Italian Car Day this is an annual event which Ace has held for many years. You are more than welcome to join us on Sunday 25th March Scooter Sunday". This event is likely to be mainly standard scooters, but perhaps some Burgman riders could show them what they are missing. The 25th March event is not on their website yet, but more about the Ace Cafe is here: Click on "Information" then "Food" to find their menu.
I will also promote this date with other maxi-scooter groups in UK.
This is an easy venue to find for those from outside London. Come on down.