JimSorry for not replying sooner. I've been away working, and just getting caught up.
Re: Outside maneuvers in a Decathalon, yes, you can do just about anything you can do inside - outside. I learned my first outside maneuvers in a 150 HP Decathalon, then switched to a Super Decathalon.
First, make sure your seat belts are as tight as you can get them. I am presuming you have double seat belts, with two separate attach points for safety.
Second, get lots of altitude.
Third, I am presuming you can fly a straight and level line upside down, and do inverted turns of at least 90 degrees right and left, and preferably, can do a level inverted 180 and 360 turn. If not, practice that first until you're good at it.
Fourth, assuming the above conditions are there, start with a 1/2 ouside loop from the bottom up. So - roll inverted, have about 160 mph and then push around until you see the horizon. You'll need a little left rudder instead of right in the push, and knowing Decathalon's, most of the time you'll probably be pushing trim to lighten the stick force.
Practice the half loop and let me know how it goes. Then we'll go from there.
Patty