Attempt at remapping evil only remaps some of the keys

Question

I'm attempting to change the mapping of evil mode, and I have placed the code below in my .emacs file.

When I start emacs some of the keys have been remapped, while others have not

These keys got remapped correctly:

e down
n back
s insert
t append
z undo
Z redo
c copy line
v paste
l previous word

These keys did not:

u up
i forward
y next word

I have changed more than what's listed here, but these are what I tested.
The relevant additions to .emacs

(define-key evil-motion-state-map "e" 'evil-next-line)
(define-key evil-motion-state-map "n" 'evil-backward-char)
(define-key evil-normal-state-map "z" 'undo)
(define-key evil-normal-state-map "Z" 'redo)
(define-key evil-normal-state-map "c" 'evil-yank)
(define-key evil-normal-state-map "v" 'evil-paste-after)
(define-key evil-motion-state-map "l" 'evil-backward-word-begin)

(define-key evil-motion-state-map "u" 'evil-previous-line)
(define-key evil-motion-state-map "i" 'evil-forward-char)
(define-key evil-motion-state-map "y" 'evil-forward-word-end)

Answer 1

The evil-normal-state-map has higher precedence than evil-motion-state-map, so since u already has a definition from evil (undo) which is located in evil-normal-state-map, the definition added in evil-motion-state-map dosen't take effect.

To fix this either remove the keymap of the key in evil-normal-state-map

(define-key evil-normal-state-map "u" nil)

Or clear all bindings in evil-normal-state-map

(setq evil-normal-state-map (make-sparse-keymap))