Hey Mike,
My frame is a size Large, but the FR30 only comes in a Small or a Large, no Medium, so I got the large (the small just felt way too small and short for my taste). I am 1.82M tall (5'11") and the large feels perfect for me. Not too big at all. I have the 180mm fork on the bike also. To be honest, the two sizes are only 1 inch difference from each other, not very much at all. So if the small feels a bit too small, you could maybe get a slightly longer stem. But like I said, between the small and large, there is only 1 inch difference, so either size you get, they are pretty similar. Hope this helps you with your decision You will love this bike, super versatile and ready to take what ever you throw its way

 HEY BRO.... WHAT SIZE IS YOUR VOLTAGE? AND HOW TALL ARE YOU?
IM 1.80M.... DO YOU THINK THE SMALL SIZE IS GOOD FOR ME?
IN MY LOCAL STORE ONLY HAVES A SMALL SIZE... I HAVE TO TAKE A DESICION

 Thanks for advice! Lets see what happening!! hahaha