new guy/lots of questions

[savy09]

Assuming they're both new, most Gy6 engines recommended use 10W40 breaking in period first 500-1000 miles and some others switch to a synthetic. I didn't switch, and stuck with Mobil1 10W40 oil on all my scooters, but that's me…also you should do a full PDI inspection of both scooters new or used. and change all fluids. The plug is right or you could go to a iridium plug w/a orange wire coil, and orange cdi for longer/better starting performance and hotter spark, I have 4000miles on them and scoot starts first time all the time
The 157QMJ is a 150cc engine Check the engine casing by the vin# and the #152QMI
Did you get a manual for each scoot nu or used?lol savy

Enjoy, and lots of luck on your buys,Ivan