Hi got a mugello 198 with reed valve ,had the kit on scoot for about 18 months .Last September the small end bearing failed causing scoring to the barrel and ruining the piston and rings.
I sent the barrel for a re plate and reassembled it with a new piston ,rings and head earlier this year .Every thing else exhaust, carb and ignition remained the same
The scooter started and ran ok in1st ,2nd and into 3rd but after 3/4 throttle the motor began to loose power and not rev on. stripped top end down again to find a piston circlip had made a break for freedom (my own fault ) scoring the barrel again about 5mm above and 10mm below transfer port
My question is firstly would a scored barrel affect the performance that drastically as I have read on various forums of people with scoring from the top to the bottom of their cylinder with no issue,or could the cylinder somehow been wrongly re plated in relation to the ports
I have also tried a mates spare carb ,stator ,cdi and replaced the fuel tap just to rule out any issues there