Hello Gents, they really are a good engine, i've had a couple over the years. For the Record, it was Masport that were using the Komatsu, not Rover. Rover opted for the suzuki and like the Briggs relationship , especially here in Aust around the late 80's with the recession the, relationship dwindled due to the exchange rate.
Overall though they are an exceptional engine, and like their 4 stroke cousins were available in standard form and in the IC trim.
Cheers, Ted