diff --git a/eos/saveddata/module.py b/eos/saveddata/module.py
index a44f8d135..a94a684e0 100644
--- a/eos/saveddata/module.py
+++ b/eos/saveddata/module.py
@@ -199,6 +199,10 @@ class Module(HandledItem, HandledCharge, ItemAttrShortcut, ChargeAttrShortcut):
         if self.owner:
             return self.owner.modules.index(self)
 
+    @property
+    def isCapitalSize(self):
+        return self.getModifiedItemAttr("volume", 0) >= 4000
+
     @property
     def hpBeforeReload(self):
         """
@@ -418,6 +422,11 @@ class Module(HandledItem, HandledCharge, ItemAttrShortcut, ChargeAttrShortcut):
         if isinstance(fit.ship, Citadel) and len(fitsOnGroup) == 0 and len(fitsOnType) == 0:
             return False
 
+        # EVE doesn't let capital modules be fit onto subcapital hulls. Confirmed by CCP Larrikin that this is dictated
+        # by the modules volume. See GH issue #1096
+        if (fit.ship.getModifiedItemAttr("isCapitalSize", 0) != 1 and self.isCapitalSize):
+            return False
+
         # If the mod is a subsystem, don't let two subs in the same slot fit
         if self.slot == Slot.SUBSYSTEM:
             subSlot = self.getModifiedItemAttr("subSystemSlot")
diff --git a/gui/builtinContextMenus/metaSwap.py b/gui/builtinContextMenus/metaSwap.py
index b2a128ce0..950a9be8e 100644
--- a/gui/builtinContextMenus/metaSwap.py
+++ b/gui/builtinContextMenus/metaSwap.py
@@ -179,8 +179,8 @@ class MetaSwap(ContextMenu):
             elif isinstance(selected_item, Implant):
                 for idx, implant_stack in enumerate(fit.implants):
                     if implant_stack is selected_item:
-                        sFit.removeImplant(fitID, idx)
-                        sFit.addImplant(fitID, item.ID, False)
+                        sFit.removeImplant(fitID, idx, False)
+                        sFit.addImplant(fitID, item.ID, True)
                         break
 
         wx.PostEvent(self.mainFrame, GE.FitChanged(fitID=fitID))
diff --git a/service/fit.py b/service/fit.py
index f44109d16..b14250f17 100644
--- a/service/fit.py
+++ b/service/fit.py
@@ -276,7 +276,7 @@ class Fit(object):
             self.recalc(fit)
         return True
 
-    def removeImplant(self, fitID, position):
+    def removeImplant(self, fitID, position, recalc=True):
         pyfalog.debug("Removing implant from position ({0}) for fit ID: {1}", position, fitID)
         if fitID is None:
             return False
@@ -284,7 +284,8 @@ class Fit(object):
         fit = eos.db.getFit(fitID)
         implant = fit.implants[position]
         fit.implants.remove(implant)
-        self.recalc(fit)
+        if recalc:
+            self.recalc(fit)
         return True
 
     def addBooster(self, fitID, itemID, recalc=True):