Late 80 early 90's CMB itallia K series, 2 stroke 15 sized nitro engine, probably ran on 15% nitro mix, by the looks of the needle valve it has setting for idle, low range, mid range and high range so that puts it in the sports category for its time period, would have sat in a boat around 24" long maybe a mid entry into the international power boat racing, or just general use. Wish bone link to the shaft, solid probably bronze doubtful its brass casting for the fly wheel, with the string grip to pull start it.
if your looking to sell it, don't be surprised if you don't get get more then £20 they arnt that special nor 'vintage' i probably have one or two laying about in my workshop somewhere
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