I've been doing some extensive work on my r90, and I finally got some numbers back on my bores. Both bores are nearly two one-thousandths out of spec. In addition, both pistons' ring grooves are one one-thousandths out of spec (the rings wobble and, as my awesome mechanic/machinist said, "skip along").
I now seek your wise council on what to do next. He says I can likely hone the bores and install some new rings and keep on trucking for another year or two. Or, I can have them bored and get new pistons (more expensive to be sure).
I can get the pistons from Motobins for ~$480. By the time I pay him for boring and whatnot, I'll be out ~$600. I've got my heads with Ted Porter now, so I'd wind up with an entirely new top end if I went that route.
What would you guys do? Money isn't tight right now, but it isn't terribly loose, either. Things tend to snowball with this bike, and I wind up treating the project like dominoes. I'm all ready in there, so I might as well, so I might as well do that too...so I might as well... You guys know how it goes .