Interesting to see the value. Mine is good original, but not to the standard of either on sale. A good idea at the time, but never going to compete with the Jap offerings of the time. Just under 5bhp and near 50 top whack. Top end lube and fragile big ends gave problems. Their ultimate demise was probably down to youngsters thrashing them; plus lack of development. Funds were needed for products giving a better financial return. Within certain constraints mine runs as sweet as a nut. A fairly rare slice of British motorcycling history.