I have multiply Baofeng radios( UV-5RV2, UV-5RE, UV-F9V2+).

I am looking for a way to change these values from the keypad only. I have tried but it always reverts back.

This has nothing to do with CHIRP. But to answer your question, you cannot permanently change any parameters of an existing memory channel while in MR mode. In VFO mode, the only parameters of an existing memory channel that can be updated are the TX frequency, T-DCS and T-CTCS (that is how repeaters are programmed).

So the only way to permanently change memory channel from the keypad is to erase it and program it back from scratch. See one of these guides.

http://www.miklor.com/COM/UV_MenuDef.php

Jim KC9HI