I have poured liqui moly 10w40 synthetic in my ybr 125 G. So far satisfied with its performance, I shared 20w50's add due to somebody above asked for it. I do think that I should pour it in summers, whereas in the winters 10w40 synthetic seems the right choice for me. My bike is almost 2,000 KMs driven. But I will continue with this oil in early summers, if I won't feel much noice and heat from the engine, maybe I'll stick to 10w40 synthetic even in full summers too because I've read somewhere that one can pour 10w40 synthetic in comparatively newer street bikes. Its quite safe, only one thing which confuses me is the bike's manual. Manual recommends 20w50 yamalube, but mera dil nahi maan raha for 20w50. Still confused and experimenting with the engine oil, myself.