GlixalATMT1-040 GY6 150cc 57.4mm Piston Set with Rings for 157QMJ Engine Scooter Moped ATV Go Karts JONWAY,JMSTAR,ROKETA,SUNL,TANK,PEACE,TAOTAO,Dongfang,Kazuma,JCL,BMS

Installed on a 150cc moped did proper break in with new cylinder (also).. no smoke no issues even layed it down because of un-cautious drivers

I've ordered GY6 pistons from a few places and this is my favorite so far. The last piston I ordered from a different supplier had rings that came with a .020 end gap. That is way too big and the motor burned oil just as bad as it did before installing the kit. The rings on this set had an end gap of .008 and .009 for the first and second ring. This is very close to perfect with the error to the small side so you can file them to be exact. Be sure you understand ring end gaps. A bigger ring makes a smaller gap. You can file a ring that is slightly too big. There is nothing you can do with a ring that is too small from the get go. Of all the inexpensive pistons this one works best in my experience.

After replacing my crank shaft I decided to replace the piston. The fit and installation was flawless

Perfect fit holds good compression no smoke good power.

On time and working great