For what it worth, I started to ride motocycle at 46 ! before I had been heavily cycling between 6 to 18 years old...maybe it did help.
My only bike experience was for few hours on 125cc...I was 35Yold
With some cash available ( THX to Microsoft Stock options) and my brand new unexpected motorcycle licence ( French to Swiss transfer !!) I wanted to own a bike.
I started to ride a 350cc for few hours and found it very easy, went to a 650cc for few days, then a 1100 Drag Star ( 2 days)and loved it!!
In Dec 98, I had the opportunity to buy a Walk drand new 1500cc, and managed it the safe way, avoiding city traffic and enjoying Swiss very COOL traffic. I was so proud of me, I decided to buy a second bike ( in Switzerland you just pay one single insurance for 2 bikes, or cars..) my kid's dream, a BMW (R1200c).
I had much more difficulites riding the BMW, not really sure why, apart from the fact that shifting gears was not as accurate as the Walk.
Bottom line since then I have only 25 000Km experience (not much) and never tried(yet) a Rune but working very hard to get one homologated in France ( very difficult)
I hope to finalize my "admin homologation" task very soon and buy my new dream...a RUNE.
Thanks to several RuneRiders members I am making progress.
Back to your question, I am not a creazyguy, but I believe if you start increasing the bike weight, you must be able to see if you feel or not confident, I mean, feeling confortable.
I hope soon to tell you my first Rune trial experience ...
BTW I am 1.75m and 80Kg