It may sound to basic,but hows jetting?Needle and seat o.k.?Floats sticking?Is the fuel old?Is the spark blue or yellow?With the float level I found it worked best for me to run it a little higher than specs,but it wasnt a starting problem with the float, it was a blubbering on rough terrain fix.Even though you just did the top end I'd check the compression,may-be a ring stuck or broke.My cold starting drill is choke on,slowly run the kick starter down a few strokes to charge the cylinder,then a a good kick with almost no throttle and it starts right up,or I may have to give it a little more throttle if its more than one kick.But it's no more than 3 kicks.If it doesnt start on the first 5or6 trys,hold the throttle open 3/4 and try that.You need fuel,spark and compression to run,did this problem develop after your long holiday?Or has this been a ongoing thing?