I tapped one of mine out to a 20 thread and used all thread to attach a few pieces and it worked worth a turd- the all thread sheared off after about 10 miles.
I'm not gentle with my bike, I figure it should take all the abuse I"d give the bike without the engine, which means I don't shy away too much from pot holes, I'm not bothered by lawns, grass and dirt... gravel doesn't doesn't scare me too much either. I suspect that when I sheared off the all thread it was because I insisted on hitting a speed bump at WOT.... lol about 13mph lol It sheared off about 1 mile later.
So whatever you shove in that square hole- make sure it's hardened!
I'd think if you were good with the welder you might be able to weld something onto it...
If you have the shaft look down near the bump head- there is often a nut that holds another piece of that drive shaft- it's like a reverse of the engine end- it's got a square hole inside a hard steel 3 inch or sho bolt loking thing with theads on the other end- this attaches to another piece that drives the bump head.
To get mine out of the craftsman shaft I had to:
remove the bump head and shield
remove the drive shaft- a 3 inche piece of aluminum or some other pot metal threaded onto the bolt witht he square hole-
Then to get that wonderful piece out I had to cut the shaft of the weedwacker just above the bearing, after that I was able to slide the bolt with the square shaft hole out of the whole assembly
IF you had access to a welder you could weld that onto the end of your ryobi drive shaft and use it to attach bmx pegs to your homelite...
You have to have steady hands though, get that off center and man you'd have one angry weed whacker... It'd get red hot and fry quick...
I attached a picture- the 2nd item from the left is what I'm talking about.
I bet if you had a carriage bolt you could cut the head off and use a die to cut a thread onto it and make something that could fit into the square hole
