diff --git a/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/ReconcilerUtils.java b/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/ReconcilerUtils.java
index 229d5e5223..e17fea7b6c 100644
--- a/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/ReconcilerUtils.java
+++ b/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/ReconcilerUtils.java
@@ -12,6 +12,7 @@
 
 import io.fabric8.kubernetes.api.builder.Builder;
 import io.fabric8.kubernetes.api.model.HasMetadata;
+import io.fabric8.kubernetes.client.CustomResource;
 import io.fabric8.kubernetes.client.KubernetesClientException;
 import io.fabric8.kubernetes.client.utils.Serialization;
 import io.javaoperatorsdk.operator.api.reconciler.Constants;
@@ -103,7 +104,9 @@ public static Object getSpec(HasMetadata resource) {
 
   public static Object setSpec(HasMetadata resource, Object spec) {
     try {
-      Method setSpecMethod = resource.getClass().getMethod("setSpec", spec.getClass());
+      Class<? extends HasMetadata> resourceClass = resource.getClass();
+      Method setSpecMethod =
+          resource.getClass().getMethod("setSpec", getSpecClass(resourceClass, spec));
       return setSpecMethod.invoke(resource, spec);
     } catch (NoSuchMethodException | InvocationTargetException | IllegalAccessException e) {
       throw new IllegalStateException("No spec found on resource", e);
@@ -167,4 +170,13 @@ private static boolean matchesResourceType(String resourceTypeName,
     return false;
   }
 
+  // CustomResouce has a parameterized parameter type
+  private static Class getSpecClass(Class<? extends HasMetadata> resourceClass, Object spec) {
+    if (CustomResource.class.isAssignableFrom(resourceClass)) {
+      return Object.class;
+    } else {
+      return spec.getClass();
+    }
+  }
+
 }
diff --git a/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/ReconcilerUtilsTest.java b/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/ReconcilerUtilsTest.java
index 1bdad72c76..ebce136775 100644
--- a/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/ReconcilerUtilsTest.java
+++ b/operator-framework-core/src/test/java/io/javaoperatorsdk/operator/ReconcilerUtilsTest.java
@@ -98,6 +98,19 @@ void setsSpecWithReflection() {
     assertThat(deployment.getSpec().getReplicas()).isEqualTo(1);
   }
 
+  @Test
+  void setsSpecCustomResourceWithReflection() {
+    Tomcat tomcat = new Tomcat();
+    tomcat.setSpec(new TomcatSpec());
+    tomcat.getSpec().setReplicas(5);
+    TomcatSpec newSpec = new TomcatSpec();
+    newSpec.setReplicas(1);
+
+    ReconcilerUtils.setSpec(tomcat, newSpec);
+
+    assertThat(tomcat.getSpec().getReplicas()).isEqualTo(1);
+  }
+
   @Test
   void loadYamlAsBuilder() {
     DeploymentBuilder builder =
@@ -134,7 +147,19 @@ void handleKubernetesExceptionShouldThrowMissingCRDExceptionWhenAppropriate() {
   @Group("tomcatoperator.io")
   @Version("v1")
   @ShortNames("tc")
-  private static class Tomcat extends CustomResource<Void, Void> implements Namespaced {
+  private static class Tomcat extends CustomResource<TomcatSpec, Void> implements Namespaced {
+
+  }
+
+  private class TomcatSpec {
+    private Integer replicas;
+
+    public Integer getReplicas() {
+      return replicas;
+    }
 
+    public void setReplicas(Integer replicas) {
+      this.replicas = replicas;
+    }
   }
 }