Well, I'm excited: We now have 11:1 99mm (1065cc) piston kits for the Virago 1000. Before some of you get too excited: these will NOT work in 920s without some machine work to the lower end. There shall be a piston kit only. There shall also be a drop-on kit: the piston kit bored into Virago 1000 cylinders with an appropriate gasket set.
A 99mm next to a stock 95mm piston. Note the shorter skirt and the dome. Also, those valve cut-aways will provide adequate clearance for up to .600' valve lift. More importantly, they give ample clearance to a .300' lift of the intake at exhaust TDC. These are designed around lifts of over .550" and durations of 300 degrees.
The pistons relative to stock bore cylinders. At the machine shop I use, a 4mm cut costs ninety dollars per hole; many other shops refuse to do it -- it wears out their less-than-adequate cutting heads. The complete kit comes with pistons slid into their respective bored cylinders with gapped rings installed. They also come with an Athena complete gasket set, and clean dowels that are a slip-fit in their bores. All threaded holes will have been chased. A warning: there are currently NO big bore head gaskets. You must either have yours hogged out, or have something made. Sorry.
I'm having a problem getting enough Virago 1000 cylinders. Eleven hundreds work, too, but they are almost as rare. Prices have gone up. I cut all prices to the bone, but the prices listed below still obtain -- and they do NOT include international shipping and insurance. I urge you to order soon as I have a very limited supply and it is first-come first-served. When I run out, it takes about five weeks to get more.
A way to run these on a 920?
In the future, these shall be special order only, and will take four to six six weeks for delivery after payment.
It can be modified: not a good idea. I recommend .030" (~.7mm) copper plate, cut by laser or water jet. A pure (or nearly so) copper gasket can be re-used indefinitely if re-annealed (a hand torch is good enough). Why don't I provide one? Well, the 99mm kit was developed for the TR1, which has a recessed gasket which is large enough. The pistons just happen to fit the (North and South) American Virago thousand. Depending on what path you take a gasket could run as little as ten dollars (each), or a whole lot more. I don't have a reasonable source for this kind of work. How badly do you want to go fast?