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Hi Pete,I think a Medium will be 18 inch, at least my XP-X (856) is. I have a 29/30 inch inside leg, so that will be OK, but I'm not sure about the reach.You could put a short stem on it to bring the bars to you.If it's a decent bike at decent money then give it a go. If it does not work out you will always get your money back & you could ride this until you get a small one.
I disagree! <GRIN>A Medium is a 16" frame857's came in four sizes:14" Small (recognized by upper shock bolt fixing being partially within the top tube)16" Medium (top tube bend between seat tube and head tube)18" Large (top tube bend directly in front of seat tube)20" Way Big (top tube bend same as Large and tall seat tube)The inch measurements above are "virtual" measurements i.e. the frame is equivalent to "traditional" frames of that size, so it's very difficult make an actual measurement that results in one of those sizes!Hope that helps!P.s. I'm 5' 8" with a 31" inside Leg and my Medium XP-X (856) is about right for me, but maybe I could wear a Large...........<GRIN> The saddle can go a long way lower on my frame (see Gallery) and the top tube is only about 35mm longer on a Medium than a Small.and I had a Medium 857 frame and it was exactly the same dimensions as my XP-X.I believe there's a few issues with shock fitting on Smalls so I think I'd always recommend a Medium if you can fit it.RegardsCol.