Early twin shocker neat but has weak clutch, followed by small-ends, piston and gearbox – any used ones will need a comprehensive engine rebuild every 15 to 20,000 miles. Later mono-shocker fixed the clutch to the extent that drag was endemic; slick gearbox sign of a good engine. Needs a rebore every 10k if thrashed. Swinging arm and mono-shock bearings go every 15k. Buzzy engine and vibes normal. As both models make excellent off-roaders, most were ruined and it’s hard to find a nice ’un.