Especially when you look at the porting layout of the 288 and 394 cylinders... Very similar, one's just a lil' more portly.
On that note, brother XP_Slinger and I got talking about wondering how the roll-out of the 3-series models went. I did a little digging on Partstree and looking at their IPL's it seems that the 3120 was the first 3xx, followed a couple years later by the 394.. They kind of started with the biggest and worked their way smaller. Funny how they are largely doing the opposite with the 5xx series, with the obvious exception of the 570, 575 and 576. But really, do those three even belong to the same family as the 550, 562, 572 and their de-tuned mag cased counterparts???
Edit: Good lord that's potentially a ridiculous thread jack. For the sake of staying on track, please consider my above query rhetorical and food for thought for another thread....