diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 260f0fcf2..b91728f5a 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -1185,6 +1185,9 @@ MainWindow::tabChanged(int index)
 {
     criticalPowerWindow->setActive(index == 2);
     performanceManagerWindow->setActive(tabWidget->widget(index) == performanceManagerWindow);
+#ifdef GC_HAVE_QWTPLOT3D
+    modelWindow->setActive(tabWidget->widget(index) == modelWindow);
+#endif
 }
 
 void
diff --git a/src/ModelPlot.cpp b/src/ModelPlot.cpp
index d09b0ea2b..ddeefe0d0 100644
--- a/src/ModelPlot.cpp
+++ b/src/ModelPlot.cpp
@@ -196,14 +196,12 @@ class ModelDataProvider : public Function
         QString describeType(int, bool);
         double maxz, minz;
         double cranklength; // used for CPV/AEPF calculation
+        bool useMetricUnits;
 };
 
 double
 ModelDataProvider::pointType(const RideFilePoint *point, int type)
 {
-    boost::shared_ptr<QSettings> settings = GetApplicationSettings();
-    bool metric = settings->value(GC_UNIT).toString() == "Metric";
-
     // return the point value for the given type
     switch(type) {
 
@@ -211,13 +209,13 @@ ModelDataProvider::pointType(const RideFilePoint *point, int type)
         case MODEL_CADENCE : return point->cad;
         case MODEL_HEARTRATE : return point->hr;
         case MODEL_SPEED :
-            if (metric == true){
+            if (useMetricUnits == true){
                 return point->kph;
             }else {
                 return point->kph * MILES_PER_KM;
             }
         case MODEL_ALT :
-            if (metric == true){
+            if (useMetricUnits == true){
                 return point->alt;
             }else {
                 return point->alt * FEET_PER_METER;
@@ -225,7 +223,7 @@ ModelDataProvider::pointType(const RideFilePoint *point, int type)
         case MODEL_TORQUE : return point->nm;
         case MODEL_TIME : return point->secs;
         case MODEL_DISTANCE :
-            if (metric == true){
+            if (useMetricUnits == true){
                 return point->km;
             }else {
                 return point->km * MILES_PER_KM;
@@ -249,9 +247,6 @@ ModelDataProvider::pointType(const RideFilePoint *point, int type)
 QString
 ModelDataProvider::describeType(int type, bool longer)
 {
-    boost::shared_ptr<QSettings> settings = GetApplicationSettings();
-    bool metric = settings->value(GC_UNIT).toString() == "Metric";
-
     // return the point value for the given type
     if (longer == true) {
         switch(type) {
@@ -260,13 +255,13 @@ ModelDataProvider::describeType(int type, bool longer)
             case MODEL_CADENCE : return ("Cadence (rpm)");
             case MODEL_HEARTRATE : return ("Heartrate (bpm)");
             case MODEL_SPEED :
-                if (metric == true){
+                if (useMetricUnits == true){
                      return ("Speed (kph)");
                 }else {
                      return ("Speed (mph)");
                 }
             case MODEL_ALT :
-                  if (metric == true){
+                  if (useMetricUnits == true){
                       return ("Altitude (meters)");
                   }else {
                       return ("Altitude (feet)");
@@ -274,7 +269,7 @@ ModelDataProvider::describeType(int type, bool longer)
             case MODEL_TORQUE : return ("Torque (N)");
             case MODEL_TIME : return ("Elapsed Time (secs)");
             case MODEL_DISTANCE :
-                if (metric == true){
+                if (useMetricUnits == true){
                     return ("Elapsed Distance (km)");
                 }else {
                     return ("Elapsed Distance (mi)");
@@ -324,6 +319,15 @@ ModelDataProvider::describeType(int type, bool longer)
  *----------------------------------------------------------------------*/
 ModelDataProvider::ModelDataProvider (BasicModelPlot &plot, ModelSettings *settings) : Function(plot)
 {
+    // get application settings
+    cranklength = 0.0;
+    useMetricUnits = false; // the default for Non-Europeans ;-)
+    boost::shared_ptr<QSettings> appsettings = GetApplicationSettings();
+    if (appsettings) {
+        cranklength = appsettings->value(GC_CRANKLENGTH).toDouble() / 1000.0;
+        useMetricUnits = appsettings->value(GC_UNIT).toString() == "Metric";
+    }
+
     // if there are no settings or incomplete settings
     // create a null data plot
     if (settings == NULL || settings->ride == NULL || settings->ride->ride() == NULL ||
@@ -336,11 +340,6 @@ ModelDataProvider::ModelDataProvider (BasicModelPlot &plot, ModelSettings *setti
         return;
     }
 
-    cranklength = 0.0;
-    boost::shared_ptr<QSettings> appsettings = GetApplicationSettings();
-    if (appsettings) {
-        cranklength = appsettings->value(GC_CRANKLENGTH).toDouble() / 1000.0;
-    }
 
     // if its not setup or no settings exist default to 175mm cranks
     if (cranklength == 0.0) cranklength = 0.175;
diff --git a/src/ModelWindow.cpp b/src/ModelWindow.cpp
index e683b0162..f0c679e14 100644
--- a/src/ModelWindow.cpp
+++ b/src/ModelWindow.cpp
@@ -46,7 +46,7 @@ ModelWindow::addStandardChannels(QComboBox *box)
     //box->addItem(tr("Longitude"), MODEL_LONG); //XXX weird values make the plot ugly
 }
 
-ModelWindow::ModelWindow(MainWindow *parent, const QDir &home) : QWidget(parent), home(home), main(parent)
+ModelWindow::ModelWindow(MainWindow *parent, const QDir &home) : QWidget(parent), home(home), main(parent), active(false)
 {
     // Layouts
     QVBoxLayout *mainLayout = new QVBoxLayout;
@@ -182,11 +182,17 @@ ModelWindow::ModelWindow(MainWindow *parent, const QDir &home) : QWidget(parent)
     connect(zpane, SIGNAL(valueChanged(int)), this, SLOT(setZPane(int)));
 }
 
+void
+ModelWindow::setActive(bool active)
+{
+    this->active = active;
+    if (active) setData(true);
+}
 void
 ModelWindow::rideSelected()
 {
     ride = main->rideItem();
-    setData(true);
+    if (active) setData(true);
 }
 
 void
diff --git a/src/ModelWindow.h b/src/ModelWindow.h
index 4a2a205da..0455ba109 100644
--- a/src/ModelWindow.h
+++ b/src/ModelWindow.h
@@ -52,6 +52,7 @@ class ModelWindow : public QWidget
     public:
 
         ModelWindow(MainWindow *, const QDir &);
+        void setActive(bool);
 
     public slots:
         void rideSelected();
@@ -75,6 +76,7 @@ class ModelWindow : public QWidget
         QDir home;
         MainWindow *main;
         bool useMetricUnits;
+        bool active;
 
         bool dirty;             // settings changed but not reploted
         ModelSettings settings; // last used settings