I use a Guardian cover for large frame bikes. It comes in black/silver with a venting pocket on the top. It is large enough to completely cover the bike and the elastic bottom will fit snugly over the front brake calipers and the trans cover in the rear. Nice snug fit! Bike was out last week in a storm with 50+ wind gusts and the cover never moved. It has a carry case that will fit in seat compartment.
I have a Burgman 400 and purchased the Nelson Rigg cover last year. I got the one recommended for the Silverwing thinking that it's (the Silverwing) slightly bigger than the 400 so the medium should be large enough for the 400. However--the medium is somewhat tight on the 400!
It does work though, but I would advise you to get the large for a 650. Good luck -it's trial & error on these things since many vendors still don't know a Burgman from a Silverwing. Glad we have this forum. Hope this helps.
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