diff --git a/tomlkit/items.py b/tomlkit/items.py
index 0204d7d..91ac812 100644
--- a/tomlkit/items.py
+++ b/tomlkit/items.py
@@ -258,13 +258,6 @@ class StringType(Enum):
     # Multi Line Literal
     MLL = "'''"
 
-    def __init__(self, value):
-        self.is_basic = lru_cache(maxsize=None)(self._is_basic)
-        self.is_literal = lru_cache(maxsize=None)(self._is_literal)
-        self.is_singleline = lru_cache(maxsize=None)(self._is_singleline)
-        self.is_multiline = lru_cache(maxsize=None)(self._is_multiline)
-        self.toggle = lru_cache(maxsize=None)(self._toggle)
-
     @classmethod
     def select(cls, literal=False, multiline=False) -> "StringType":
         return {
@@ -302,19 +295,19 @@ def invalid_sequences(self) -> Collection[str]:
     def unit(self) -> str:
         return self.value[0]
 
-    def _is_basic(self) -> bool:
+    def is_basic(self) -> bool:
         return self in {StringType.SLB, StringType.MLB}
 
-    def _is_literal(self) -> bool:
+    def is_literal(self) -> bool:
         return self in {StringType.SLL, StringType.MLL}
 
-    def _is_singleline(self) -> bool:
+    def is_singleline(self) -> bool:
         return self in {StringType.SLB, StringType.SLL}
 
-    def _is_multiline(self) -> bool:
+    def is_multiline(self) -> bool:
         return self in {StringType.MLB, StringType.MLL}
 
-    def _toggle(self) -> "StringType":
+    def toggle(self) -> "StringType":
         return {
             StringType.SLB: StringType.MLB,
             StringType.MLB: StringType.SLB,
diff --git a/tomlkit/toml_char.py b/tomlkit/toml_char.py
index b6260e9..b4bb411 100644
--- a/tomlkit/toml_char.py
+++ b/tomlkit/toml_char.py
@@ -1,16 +1,8 @@
 import string
 
-from functools import lru_cache
-
 
 class TOMLChar(str):
     def __init__(self, c):
-        self.is_bare_key_char = lru_cache(maxsize=None)(self._is_bare_key_char)
-        self.is_kv_sep = lru_cache(maxsize=None)(self._is_kv_sep)
-        self.is_int_float_char = lru_cache(maxsize=None)(self._is_int_float_char)
-        self.is_ws = lru_cache(maxsize=None)(self._is_ws)
-        self.is_nl = lru_cache(maxsize=None)(self._is_nl)
-        self.is_spaces = lru_cache(maxsize=None)(self._is_spaces)
         super().__init__()
 
         if len(self) > 1:
@@ -23,37 +15,37 @@ def __init__(self, c):
     NL = "\n\r"
     WS = SPACES + NL
 
-    def _is_bare_key_char(self) -> bool:
+    def is_bare_key_char(self) -> bool:
         """
         Whether the character is a valid bare key name or not.
         """
         return self in self.BARE
 
-    def _is_kv_sep(self) -> bool:
+    def is_kv_sep(self) -> bool:
         """
         Whether the character is a valid key/value separator or not.
         """
         return self in self.KV
 
-    def _is_int_float_char(self) -> bool:
+    def is_int_float_char(self) -> bool:
         """
         Whether the character if a valid integer or float value character or not.
         """
         return self in self.NUMBER
 
-    def _is_ws(self) -> bool:
+    def is_ws(self) -> bool:
         """
         Whether the character is a whitespace character or not.
         """
         return self in self.WS
 
-    def _is_nl(self) -> bool:
+    def is_nl(self) -> bool:
         """
         Whether the character is a new line character or not.
         """
         return self in self.NL
 
-    def _is_spaces(self) -> bool:
+    def is_spaces(self) -> bool:
         """
         Whether the character is a space or not
         """