AN HISTORICALLY IMPORTANT Honda CB750 is up for grabs at the H&H Classics auction on March 4, at the National Motorcycle Museum. A late pre-production model, it is one of only four built, only two are known to still exist. Although it is estimated at £35,000-£40,000, the other machine sold for £88,900 in 2014. H&H Classics believe a world record price is in the offing. The bike for sale with H&H is a rare machine, mostly hand-made in Japan in 1968.