From what I can see it looks to be a 69 Digger or 69 Sprint with the rear swing arm having the bracket for a chain tensioner. Because those bikes didn't use a jackshaft even thou they had the brackets for a jackshaft chain came straight off engine to wheel. Plus if the rear shocks are original only digger and sprint used them as far as I know. But do a little more homework ask Brandt at Rupparts.com and show that picture to him he will know for sure. Also someone cut the jackshaft bracket off to fit that briggs engine in it I bet. Good luck