Chainsaw Repair

I love the 61 thru 272 family, as well as the Jonny 625/630/670 versions. But the 372/2171 chassis that replaced it was a significant improvement. More power, much better anti-vibe, better cylinder design.

You are correct in that the 268XP and 272XP really only differ in the extra 2mm bore of the 272. Like most examples where two similar models differ by only a few CC's, performance is very close with differences noticed as the wood gets bigger. They are both of what would be called the second generation on this chassis, where as a 266XP is from the early generation. Early being defined as twin coil ignition and lower profile muffler and top cover.

There were two versions of the 268: the closed port XP and the later open port which was not an XP. The open port 268 arrived at about the same time the 272XP replaced the 268XP. For at least part of the time it was on the market, the open port 268 was given the "special" moniker. That open port cylinder was shared with the 268K cutoff saw as well as your gray top 66. The only other cylinder that was shared by two models was the 62CC jug used on both the 162SE and the Jonsered 630 Super. Easy saws to work on, but interchangability between different models can be tricky until you get familiar with them.