Be careful, do not use too much grease. Too much will cause excess friction and the cable will break (been there, done that - a long time ago). I just lubed my speedo cable with synthetic dri-slide from an aerosol container. Cable works fine, no noise, and the speedo needle very steady at all speeds.
America: Land of the Free!
1977 300D: 300,000+ miles
American Honda: Factory Trained Technician & Honor Grad.
Technical Advisor to Am. Honda;
Supervisor of Maintenance largest tree care co. in US for offices in Tex.