diff --git a/tokio-util/src/codec/framed.rs b/tokio-util/src/codec/framed.rs
index 043b43841..8a344f90d 100644
--- a/tokio-util/src/codec/framed.rs
+++ b/tokio-util/src/codec/framed.rs
@@ -368,7 +368,10 @@ pub struct FramedParts<T, U> {
 
 impl<T, U> FramedParts<T, U> {
     /// Create a new, default, `FramedParts`
-    pub fn new(io: T, codec: U) -> FramedParts<T, U> {
+    pub fn new<I>(io: T, codec: U) -> FramedParts<T, U>
+    where
+        U: Encoder<I>,
+    {
         FramedParts {
             io,
             codec,