I think you would be safe going to 65 lbs . back both limbs off equaly for even tiller . I think your letoff is 65% on that model which is a excelet bow by the way . One thing to check is your string and cabel condition I'd replace them if they look old or even if they dont this bow may have some old strings on it . You can e-mail the company at this link
http://fulldraw.net/bear/jennings.html
or call them I'd do that first before I droped it to 65 lbs and I think 60 lbs is too light for a 80 lb bow
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