On my triple (Ultegra 9-speed), I can run all but 1 or two cogs on either the smallest or largest chain rings. Not that I cross chain like that when riding, but when I tune up the FD, those are the limits. On the middle ring, I can run all 9 cogs without rubbing. My wife's half bike is the same and so is our tandem. These are all road machines. Sounds like it needs some tuning to me, or perhaps the "gate" on the Sora is a bit smaller... OHB