How To Treat Pain In Knee Post Knee Replacement Surgery?

I have had both total knee replacements and now have some pain in my knees and right hip. could this be because I am not a very active person and will leg presses and riding a stat. bike help. I am 6-4 and weigh approx. 270 & 280 should I lose weight will that help? I play golf and adjust but have trouble throwing my legs over my motorcycle at times.