So I have a SR 125 fitted with a 172 Malossi kit, 25 mm dellorto running 106 main 50 pilot and d36 needle, pm gear up kit and modded airbox. Now I've done 400 miles no issues running well with good plug colour. So I decided to put an expansion pipe on it . I fitted a Tecnigas RS ii and I know not the best for performance but I assume not worse than original. So fitted it yesterday evening and rode to work 12 miles away all seemed good until riding home bike just stopped with no warning. I removed plug and it was white and blistered and piston has melted and wrecked barrel could this just be caused by fitting the pipe.
