RickH

yep it's easy I have done it. Drilled a hole through the frame upright and added a "Pip Pin" to secure the pulley

I fly from sea level, what size and brand prop you using? I am running the supplied Helix 130cm carbon prop.

I measured my new ( 35hrs ) Atom80 with 130cm prop as having 44kg of thrust, well less than the 55kg claimed. my engine is only pulling 9500rpm, not 9800rpm so that may affect max thrust?

I have a PAP Tinox Atom80 with MY20 engine. Advertised thrust with 130cm prop is 55kgs @ 9800RPM. I've measured mine at 44kg @ 9500RPM. Has anyone measured the thrust on their Atom80? 35hrs on my motor, correct run in procedure, correct fuel/oil mix 66:1 ( 1.5% ). My engine has registered a max RPM of 9530 so far, ( not getting max 9800 ). I can't imagine 300RPM making a great difference in thrust ( 9800 instead of 9530 ) The supplied instruction manual was last updated September 2018, it does not have any information re: the new carb with high speed tuning jet. I fly from sea level, is it possible the high speed jet needs adjusting from factory setting?