Lostykins

Ok, I'm not sure if this is supposed to go in this board, nor weather this is an actual bug. Though, I presume so considering I can enter Route 16 without a bike, and my friend can't. - So basically, we both do not have a bike. However, when entering Route 16, I can enter. However my friend can't. We've done all parts of the game together, so we've missed nothing. The only difference is, I have a Shiny Arcanine Mount, and a Lapras mount. Is is possible that one of those mounts is causing it?