I'm looking for data concerning an R65 hop-up that involved re-sleeving R65 cylinders to 94mm bore with Venolia pistons. I've got a bike that outwardly appears stock (ignoring the 34mm flat slide Mikunis), but after pulling the head to repair a nicked fin, discovered the Venolia and larger bore. The head has had work done also as evidenced by a cup shaped washer between the springs (yep, twin valve springs) and head. I've heard of cutting down R80 cylinders to match the R65's shorter stroke, but wouldn't have imagined an R100 sleeve fitting into the barrel, much less the block. Evidently the block would have been bored as well. The barrels and head are R65 as evidenced by the 6.5 at the cylinder bases and the numbers on the heads. Any of you know anything about this modification?