one idea is to by the bike and insure it, but do not use it on a regular basis - that is only if the insurance carries over the NCB to cars, as mentioned earlier

couple of mates have insured 50cc non runners to keep their NCB for their bike insurance as some bike insurers say if your off a bike for a year then you loose your NCB even though you are driving a car in the meantime

if you are not confident on a bike then keep clear, as confidence is the one of the major factors in keeping you alive when one day it all starts going wrong