diff --git a/maas/files/curtin_userdata_amd64_generic_trusty b/maas/files/curtin_userdata_amd64_generic_trusty
index b644934..0cc4a7d 100644
--- a/maas/files/curtin_userdata_amd64_generic_trusty
+++ b/maas/files/curtin_userdata_amd64_generic_trusty
@@ -25,7 +25,7 @@
 {% if cluster.saltstack_repo_trusty.startswith('deb') %}
   {%- set saltstack_repo = cluster.saltstack_repo_trusty -%}
 {%- else %}
-  {%- set saltstack_repo = 'deb [arch=amd64]' + cluster.saltstack_repo_trusty -%}
+  {%- set saltstack_repo = 'deb [arch=amd64] ' + cluster.saltstack_repo_trusty -%}
 {%- endif %}
   apt_01_set_repo: ["curtin", "in-target", "--", "sh", "-c", "echo '{{ saltstack_repo }}' >> /etc/apt/sources.list.d/mcp_saltstack.list"]
   apt_03_update: ["curtin", "in-target", "--", "apt-get", "update"]
diff --git a/maas/files/curtin_userdata_amd64_generic_xenial b/maas/files/curtin_userdata_amd64_generic_xenial
index 8c60529..82beaea 100644
--- a/maas/files/curtin_userdata_amd64_generic_xenial
+++ b/maas/files/curtin_userdata_amd64_generic_xenial
@@ -25,7 +25,7 @@
 {% if cluster.saltstack_repo_xenial.startswith('deb') %}
   {%- set saltstack_repo = cluster.saltstack_repo_xenial -%}
 {%- else %}
-  {%- set saltstack_repo = 'deb [arch=amd64]' + cluster.saltstack_repo_xenial -%}
+  {%- set saltstack_repo = 'deb [arch=amd64] ' + cluster.saltstack_repo_xenial -%}
 {%- endif %}
   apt_01_set_repo: ["curtin", "in-target", "--", "sh", "-c", "echo '{{ saltstack_repo }}' >> /etc/apt/sources.list.d/mcp_saltstack.list"]
   apt_03_update: ["curtin", "in-target", "--", "apt-get", "update"]
diff --git a/maas/files/curtin_userdata_arm64_generic_xenial b/maas/files/curtin_userdata_arm64_generic_xenial
index 3d6b34b..af9a047 100644
--- a/maas/files/curtin_userdata_arm64_generic_xenial
+++ b/maas/files/curtin_userdata_arm64_generic_xenial
@@ -25,7 +25,7 @@
 {% if cluster.saltstack_repo_xenial.startswith('deb') %}
   {%- set saltstack_repo = cluster.saltstack_repo_xenial -%}
 {%- else %}
-  {%- set saltstack_repo = 'deb [arch=amd64]' + cluster.saltstack_repo_xenial -%}
+  {%- set saltstack_repo = 'deb [arch=amd64] ' + cluster.saltstack_repo_xenial -%}
 {%- endif %}
 {#- NOTE: Re-use amd64 repos on arm64 since most packages are arch independent #}
   apt_01_set_repo: ["curtin", "in-target", "--", "sh", "-c", "echo '{{ saltstack_repo }}' >> /etc/apt/sources.list.d/mcp_saltstack.list"]