I might have the world's first 64.9 cc four stroke conversion...Sthil BR550 backpack blower..
24-8 prop-, 6000 rpm, 1200 rpm idle...Weighs about 6 lbs...There are no flat places on the back for the mount, you have to get real creative...Will post some pictures after I get it off the test stand....It's gonna take some tweaking on the carb, I can't get it rich enough without closing the choke partway, but maybe a carb from a Ryobi 4 stroke would work..It comes with a proprietary Zama, 2 needles, but it seems to be way too big...I put a gasket under it with just 2 small 1/4 inch holes in it, and it works without the choke closed..Interesting project...
Captin John will love this one
Only 1 other problem so far, it runs clockwise..Pusher prop needed...[8D]