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Its a 16" the top shock mount is the same as my 855 tucked up in the frame
Re size; I have the original receipt which states 16 inch. The actual frame measures from the centre of the BB vertically to the top of the top tube just above the rear sus mount = 16 inches. Or centre of BB to top of seat post = 18 & half inches.Don't want to start a frame measurement war though.It's not my bike, just selling it as part of a late friend's estate. He was about 5 foot 7 (1 metre 70 cm) so would say definitely a small.