Greg Ian's bike is a US Hallman not UK / NL HL
Johnny O I certainly remember Vertually every change on everything MX from H S and Y from 76 to 85
it's not the technology changes that made the Honda better it, the Aberg has no steering lock and it was/is too tall, the C&J was based on the 78/79 CR250R which had steering lock and did turn.
I raced the Aberg at Jilliby, Dunlop Lea and Foster Park, it only worked for me at Jilliby with its berms, Dunlop Lea was a killer with the deep sand and ruts, Foster Park was fun.
I rode both bikes as registered trail bikes but there is no comparison.
I have CCMs and other trick Thumpers but the C&J is the best so far,
I say so far since I honestly think the HS that GMC has built will be even better,