I tore up my shoulder 3 years ago and had 40-50 lb limbs put on my 65 lb Z7. shoulder has healed and am comfortable shooting with the current limbs maxed at 50. Now would like to slowly work up to 55. I saw an earlier thread where someone is using 50-60 limbs at 45. would it be safe to have my 55-65 limbs put back on and backed off to 50? if not 50, how low would be safe? thanks. great forum and great bow.