I'm new to this forum. I'm contemplating building a CB350 race bike for classic racing in QLD. I've had a look at the Classic rules in Motorcycling Australia handbook but I am not quite sure of a couple of aspects. For example, a 1989 CB350 (Period 4)has drum front brake - I think from about 1971 the same model bike had a disc front brake. Can the 1989 model use the later model disc brake setup?