diff --git a/src/KOKKOS/fix_spring_self_kokkos.cpp b/src/KOKKOS/fix_spring_self_kokkos.cpp
index 9ba796b1ab..1b6d45ead7 100644
--- a/src/KOKKOS/fix_spring_self_kokkos.cpp
+++ b/src/KOKKOS/fix_spring_self_kokkos.cpp
@@ -79,6 +79,9 @@ void FixSpringSelfKokkos<DeviceType>::init()
 {
   FixSpringSelf::init();
 
+  if (kstyle != CONSTANT)
+    error->all(FLERR, "Fix spring/self/kk does not support variable spring constants (yet)");
+
   if (utils::strmatch(update->integrate_style,"^respa"))
     error->all(FLERR,"Cannot (yet) use respa with Kokkos");
 }
diff --git a/src/fix_spring_self.cpp b/src/fix_spring_self.cpp
index 797255c381..f8720a9217 100644
--- a/src/fix_spring_self.cpp
+++ b/src/fix_spring_self.cpp
@@ -32,8 +32,6 @@
 using namespace LAMMPS_NS;
 using namespace FixConst;
 
-enum { NONE, CONSTANT, EQUAL, ATOM };
-
 /* ---------------------------------------------------------------------- */
 
 FixSpringSelf::FixSpringSelf(LAMMPS *lmp, int narg, char **arg) :
diff --git a/src/fix_spring_self.h b/src/fix_spring_self.h
index e3220b8cfd..9699ca33f3 100644
--- a/src/fix_spring_self.h
+++ b/src/fix_spring_self.h
@@ -26,6 +26,7 @@ namespace LAMMPS_NS {
 
 class FixSpringSelf : public Fix {
  public:
+  enum { NONE, CONSTANT, EQUAL, ATOM };
   FixSpringSelf(class LAMMPS *, int, char **);
   ~FixSpringSelf() override;
   int setmask() override;