I'd guess Suzuki are probably the top make in UK just on the basis several of the major manufacturers seem to use them as a preferred brand if the customer indicates no preference - Humber and Ribcraft for example - many of the boat tests you see in mags have a Suzuki on. Having said that I don't know what proportion of the new outboard sales market sits with new boats and what proportion are repowers.
Evinrude have been around for 100 years so they probably have the most cumulative sales
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