diff --git a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyFrameEncoder.java b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyFrameEncoder.java
index e2a9f062ff..83ebb72964 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyFrameEncoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyFrameEncoder.java
@@ -65,9 +65,7 @@ public class SpdyFrameEncoder extends MessageToByteEncoder<SpdyFrame> {
         ctx.channel().closeFuture().addListener(new ChannelFutureListener() {
             @Override
             public void operationComplete(ChannelFuture future) throws Exception {
-                synchronized (headerBlockEncoder) {
-                    headerBlockEncoder.end();
-                }
+                headerBlockEncoder.end();
             }
         });
     }
diff --git a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockJZlibEncoder.java b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockJZlibEncoder.java
index 912b7d828c..1e66a18fca 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockJZlibEncoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockJZlibEncoder.java
@@ -98,7 +98,7 @@ class SpdyHeaderBlockJZlibEncoder extends SpdyHeaderBlockRawEncoder {
     }
 
     @Override
-    public synchronized ByteBuf encode(ChannelHandlerContext ctx, SpdyHeadersFrame frame) throws Exception {
+    public ByteBuf encode(ChannelHandlerContext ctx, SpdyHeadersFrame frame) throws Exception {
         if (frame == null) {
             throw new IllegalArgumentException("frame");
         }
@@ -119,7 +119,7 @@ class SpdyHeaderBlockJZlibEncoder extends SpdyHeaderBlockRawEncoder {
     }
 
     @Override
-    public synchronized void end() {
+    public void end() {
         if (finished) {
             return;
         }
diff --git a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockZlibEncoder.java b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockZlibEncoder.java
index b6971a4e62..320167dd49 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockZlibEncoder.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/spdy/SpdyHeaderBlockZlibEncoder.java
@@ -59,7 +59,7 @@ class SpdyHeaderBlockZlibEncoder extends SpdyHeaderBlockRawEncoder {
     }
 
     @Override
-    public synchronized ByteBuf encode(ChannelHandlerContext ctx, SpdyHeadersFrame frame) throws Exception {
+    public ByteBuf encode(ChannelHandlerContext ctx, SpdyHeadersFrame frame) throws Exception {
         if (frame == null) {
             throw new IllegalArgumentException("frame");
         }