Proper oil for GY6
 

I just changed the oil in my scooter (Wolf RX 50) to get rid of the break in oil. I replaced it with 15W40 like the manual and sticker on engine said to. It seems like 15W40 oil is mostly used in diesel or heavy duty gas engines. Should i still be using this type of oil in my scooter? Also would it be bad if I went down to 10W40?

my manual says 10w30... and i use only the best REPSOL racing oil 10w40... i will report later how it likes or not ;)

There are a lot of opinions on this matter, I use Amsoil 10w40 scooter 4 stroke oil and it works great from winter to summer. Try to use scooter specific oil, they are designed to not foam up under high crank pressure which scooters have a problem with. Amsoil, bel rey, and maxim all make scooter specific oil