"Tas kamu lebih berat."

Translation: Your bag is heavier.

[DarkHylian]

By the way, heavier is a comparative word, for me the sentence lacks somewhat to compare.

"Your bag is heavier than my bag"
Tas kamu lebih berat dari tas aku.

[KoenWillem]

Why would "Your bag is more heavy" be incorrect?

[DarkHylian]

Because of English rules.

More heavy doesn't exist, it's heavier.

Many short words apply that construction. (Eg. Happy/happier, naughty/naughtier, ...)

[Mik2645]

I can't understand the male voice