I'm planning on buying a road bike just to travel from school and back. I don't plan on racing or anything. I've looked at a chart for the size of the bike that ur supposed to ride for ur height, but I'm trying to buy a bike for cheap so I don't have a whole lot of size options. I'm about 6 foot tall and on the chart I'm looking at it shows that the bike should be about 60cm. Is it a huge deal if i were to buy a bike that was a couple cm off of that and if it doesn't matter what would be the smallest size i should buy?