i have a picco .21 in a mbx4 ( yah i know oldy but goody) would like a lil help with ID of engine and possibly tuning specs if anyone knows them off hand,it runs great goes great handles great but gets very hot anyone know it please help me save an old timer from the dreadful pop.the pics are in my photos

found out upon cleaning the mbx4 that my picco .21 was modded by Ron Paris
which would explain why it can eat up my buddy's force 28...anyone know of his engine mods? i would like to know what i have in it,but dont want to pull apart a running engine for nothing

The only tip I can give you is the pico's of that time had flat slide carbs. When they would come in to pit the motor would stay at high idle for 3 to 5 secs then come down to a nice low idle. If it didnt do that it was to lean. They were a little touchy to tune but once there they were rock solid. The Paris mods were pretty sick. Just insain how much power and speed they had. When tuned correctly they were bullet proof too.

HTH

D. King is correct. Ron's motors were ballistic. He used to pack instructions with them as to how to tune as they are sensitive. Idle seemed to have an impact on every other setting. Good luck. If you get it right that motor will be super fast.