diff --git a/src/main/java/ratpack/zipkin/internal/ZipkinHttpClientImpl.java b/src/main/java/ratpack/zipkin/internal/ZipkinHttpClientImpl.java
index 664cb18..479ea94 100644
--- a/src/main/java/ratpack/zipkin/internal/ZipkinHttpClientImpl.java
+++ b/src/main/java/ratpack/zipkin/internal/ZipkinHttpClientImpl.java
@@ -271,7 +271,8 @@ public RequestSpec maxContentLength(int numBytes) {
 
         @Override
         public RequestSpec responseMaxChunkSize(final int numBytes) {
-            return null;
+            this.delegate.responseMaxChunkSize(numBytes);
+            return this;
         }
 
         @Override