Originally Posted by
stapfam
30" inseam is going to be your problem. Thats My inseam and I am 5'6" short. I ride a variety of sizes- but you will have to look at the convention of Mountain bikers using smaller frames and longer seat posts.
Do not go by Frame size to your height- Sort the toptube as being comfortable and fit a longer seat tube.
Ok- I am extreme but I ride a 15" as my main MTB. I also ride a 51 on road bikes But On mountain bikes I also ride a 17" and a 19" Different manufacturers with different Geometry. And don't go for the same ride position on an MTB as a road bike. Road bikes do have a lower more stretched out riding position. Attachment is of my MTB set up for offroad. For road use I fit slicks and Flip the stem to give me a lower bar position.
Guess you have never seen Lance Armstrong ride a mtb. He won in Leadville this year riding his 19.5" Trek Fuel dually with 625mm top tube and 120mm stem. He is likely more stretched out on his mtb with hands on his grips than he is on his Madone with 580mm top tube and 130mm stem on the hoods.
Fast riders on either mtb or road like aggressive positions on each.