Big Bore High Compression Pistons

Short answer, if your stock bore is worn out you will find that there are NO OEM pistons available, so: Yes. Long answer: somewhere in that garage under a tarp is an old Virago cruiser, probably unused since its starter gears refused to engage. A second adolescence comes upon you. The V Twin looks an awful lot like an old Vincent - and those were _fast_. Café racers are making a comeback. You have a little disposable income. You dream of carving corners and blasting out of them. It would be nice to have a bit more lower end power AND be able to scoot past redline. It would be humiliating to be left in the dust by desmo Ducatis and thirty year old JP fours. So, once again: Yes.

So fix the starter and see if/how the bike runs. Chances are that the top two pistons rings will be gummed shut and the bores scarred. The carbs will be full of mung and are difficult to tune at best. The cams and rockers may be overly worn.

Unless the valve train is absolute trash, your first acquisition will be piston kits. Once you feel the urge they have and realize the potential for more, cam sets and spring kits will be in order. Feeling something holding you back and the sputtering and difficulty keeping them in sync will have you pitching the carbs, probably in favor of a Mikuni TM40-6 pair. They drop right on and are easy to tune. Then you may tackle the exhaust.

More to come . . .

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