What does it mean no mamas wey

Question

No mamas wey

Answer 1

From a 10 second Google Search:

no mames guey A Spanish slang phrase commonly used by Mexicans. Geuy means a jerk (other translations for guey are dude, bro, punk, and more), but young Mexican people use it to adress their friends in a teasing manner. The whole phrase "no mames guey" translates as "You must be kidding, man!" but most people use it refering to its other definitions, such as (vulgar examples deleted)
1. Non agressive example ("you must be kidding"):

"Yea, so I just bought a new TV which is flatscreen and HD!"

"No mames guey! Thats awsome."

1. Agessive example (vulgar example deleted)

"Hey, will you ask your mom how much I owe her for last night?"

"No mames guey!"