I'm thinking you're probably right, as I said the steerer tube is 195mm long and it's out of a 20" frame. (nice mixture of metric and imperial there I know!)
It with much regret after discovering a crack in the frame that I am breaking my pride and joy (owned almost from new), firstly although the frame is cracked and should not be ridden if anyone would like to use it for display purposes, please drop me a pm and I will be more than happy to discuss...