diff --git a/src/RequestManager.test.ts b/src/RequestManager.test.ts
index d666f52..dc037d2 100644
--- a/src/RequestManager.test.ts
+++ b/src/RequestManager.test.ts
@@ -39,12 +39,4 @@ describe("client-js", () => {
     c.request("foo", []);
   });
 
-  it("can handle onData", () => {
-    const transport = new EventEmitterTransport("foo://unique-uri");
-    const c = new RequestManager([transport]);
-    const data = "{\"result\": \"bar\", \"id\": 1}";
-    c.request("foo", []);
-    c.onData(data);
-  });
-
 });
diff --git a/src/RequestManager.ts b/src/RequestManager.ts
index e5d3cad..6ae961d 100644
--- a/src/RequestManager.ts
+++ b/src/RequestManager.ts
@@ -47,7 +47,7 @@ class RequestManager {
       transport.close();
     });
   }
-  public onData(data: string): void {
+  private onData(data: string): void {
     const parsedData = JSON.parse(data);
     if (typeof parsedData.result === "undefined") {
       return;