possible you may need to replace diaphragms in both carbs , 12,000 miles or so. not cheap to buy but it worked for me . simple enough to fit . You also have to get the "security" hexagon tool (it has...
On the early 80's Viragos 81-83 the speedometer cable attaches to the front wheel and go's up behind the headlight into the speedometer. The gauges them selves attach to the triple trees via bolts....
Engine Type Liquid cooled, SOHC, 5-valve, 660cc, four-stroke single Bore x Stroke 100mm x 84mm Compression Ratio 9.2:1 Carburetion Dual Mikuni 33mm BSR Ignition CDI Starting System Electric...