diff --git a/lib/model/shifter_types.dart b/lib/model/shifter_types.dart
index 9d34111..cb57b6b 100644
--- a/lib/model/shifter_types.dart
+++ b/lib/model/shifter_types.dart
@@ -112,6 +112,7 @@ enum TrainerConnectionState {
   idle,
   connecting,
   pairing,
+  connected,
   discoveringFtms,
   ftmsReady,
   error,
@@ -131,6 +132,8 @@ class TrainerStatus {
         return 'Connecting';
       case TrainerConnectionState.pairing:
         return 'Pairing';
+      case TrainerConnectionState.connected:
+        return 'Connected';
       case TrainerConnectionState.discoveringFtms:
         return 'Discovering FTMS';
       case TrainerConnectionState.ftmsReady:
@@ -148,9 +151,11 @@ class TrainerStatus {
         case 2:
           return const TrainerStatus(state: TrainerConnectionState.pairing);
         case 3:
+          return const TrainerStatus(state: TrainerConnectionState.connected);
+        case 4:
           return const TrainerStatus(
               state: TrainerConnectionState.discoveringFtms);
-        case 4:
+        case 5:
           return const TrainerStatus(state: TrainerConnectionState.ftmsReady);
         default:
           return const TrainerStatus(state: TrainerConnectionState.idle);
@@ -160,7 +165,7 @@ class TrainerStatus {
     if (raw is List && raw.isNotEmpty) {
       final variant = raw.first;
       final value = raw.length > 1 ? raw[1] : null;
-      if (variant is int && variant == 5) {
+      if (variant is int && (variant == 5 || variant == 6)) {
         return TrainerStatus(
           state: TrainerConnectionState.error,
           errorCode: value is int ? value : null,
@@ -173,7 +178,7 @@ class TrainerStatus {
       if (entry != null) {
         final key = entry.key;
         final value = entry.value;
-        if ((key is int && key == 5) ||
+        if ((key is int && (key == 5 || key == 6)) ||
             (key is String && key.toLowerCase().contains('error'))) {
           return TrainerStatus(
             state: TrainerConnectionState.error,
@@ -191,6 +196,9 @@ class TrainerStatus {
       if (normalized.contains('pairing')) {
         return const TrainerStatus(state: TrainerConnectionState.pairing);
       }
+      if (normalized.contains('connected')) {
+        return const TrainerStatus(state: TrainerConnectionState.connected);
+      }
       if (normalized.contains('discover')) {
         return const TrainerStatus(
             state: TrainerConnectionState.discoveringFtms);
diff --git a/lib/pages/device_details_page.dart b/lib/pages/device_details_page.dart
index f8dd297..4b5418f 100644
--- a/lib/pages/device_details_page.dart
+++ b/lib/pages/device_details_page.dart
@@ -62,6 +62,7 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
   bool _hasLoadedGearRatios = false;
   String? _gearRatiosError;
   List<double> _gearRatios = const [];
+  int _defaultGearIndex = 0;
 
   @override
   void initState() {
@@ -245,20 +246,28 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
     }
 
     setState(() {
-      _gearRatios = result.unwrap();
+      final data = result.unwrap();
+      _gearRatios = data.ratios;
+      _defaultGearIndex = data.defaultGearIndex;
       _isGearRatiosLoading = false;
       _hasLoadedGearRatios = true;
       _gearRatiosError = null;
     });
   }
 
-  Future<String?> _saveGearRatios(List<double> ratios) async {
+  Future<String?> _saveGearRatios(
+      List<double> ratios, int defaultGearIndex) async {
     final shifter = _shifterService;
     if (shifter == null) {
       return 'Status channel is not ready yet.';
     }
 
-    final result = await shifter.writeGearRatios(ratios);
+    final result = await shifter.writeGearRatios(
+      GearRatiosData(
+        ratios: ratios,
+        defaultGearIndex: defaultGearIndex,
+      ),
+    );
     if (result.isErr()) {
       return 'Could not save gear ratios: ${result.unwrapErr()}';
     }
@@ -269,6 +278,9 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
 
     setState(() {
       _gearRatios = List<double>.from(ratios);
+      _defaultGearIndex = ratios.isEmpty
+          ? 0
+          : defaultGearIndex.clamp(0, ratios.length - 1).toInt();
       _hasLoadedGearRatios = true;
       _gearRatiosError = null;
     });
@@ -495,6 +507,7 @@ class _DeviceDetailsPageState extends ConsumerState<DeviceDetailsPage> {
                     const SizedBox(height: 16),
                     GearRatioEditorCard(
                       ratios: _gearRatios,
+                      defaultGearIndex: _defaultGearIndex,
                       isLoading: _isGearRatiosLoading,
                       errorText: _gearRatiosError,
                       onRetry: _loadGearRatios,
diff --git a/lib/service/shifter_service.dart b/lib/service/shifter_service.dart
index 4de7d70..0892067 100644
--- a/lib/service/shifter_service.dart
+++ b/lib/service/shifter_service.dart
@@ -20,6 +20,8 @@ class ShifterService {
   Stream<CentralStatus> get statusStream => _statusController.stream;
 
   static const int _gearRatioSlots = 32;
+  static const int _defaultGearIndexOffset = _gearRatioSlots;
+  static const int _gearRatioPayloadBytes = _gearRatioSlots + 1;
   static const double _maxGearRatio = 255 / 64;
   static const int _gearRatioWriteMtu = 64;
 
@@ -56,7 +58,7 @@ class ShifterService {
     return writeCommand(UniversalShifterCommand.connectToDevice);
   }
 
-  Future<Result<List<double>>> readGearRatios() async {
+  Future<Result<GearRatiosData>> readGearRatios() async {
     final readRes = await _bluetooth.readCharacteristic(
       buttonDeviceId,
       universalShifterControlServiceUuid,
@@ -67,25 +69,43 @@ class ShifterService {
     }
 
     final raw = readRes.unwrap();
-    if (raw.length > _gearRatioSlots) {
+    if (raw.length > _gearRatioPayloadBytes) {
       return bail(
-        'Invalid gear ratio payload length: expected at most $_gearRatioSlots, got ${raw.length}',
+        'Invalid gear ratio payload length: expected at most $_gearRatioPayloadBytes, got ${raw.length}',
       );
     }
 
-    final normalizedRaw = List<int>.filled(_gearRatioSlots, 0, growable: false);
+    final normalizedRaw = List<int>.filled(
+      _gearRatioPayloadBytes,
+      0,
+      growable: false,
+    );
     for (var i = 0; i < raw.length; i++) {
       normalizedRaw[i] = raw[i];
     }
 
-    final ratios = normalizedRaw
-        .where((v) => v > 0)
-        .map((v) => _decodeGearRatio(v))
-        .toList(growable: false);
-    return Ok(ratios);
+    final ratios = <double>[];
+    for (var i = 0; i < _gearRatioSlots; i++) {
+      final value = normalizedRaw[i];
+      if (value == 0) {
+        break;
+      }
+      ratios.add(_decodeGearRatio(value));
+    }
+
+    final defaultIndexRaw = normalizedRaw[_defaultGearIndexOffset];
+    final defaultGearIndex = ratios.isEmpty
+        ? 0
+        : defaultIndexRaw.clamp(0, ratios.length - 1).toInt();
+    return Ok(
+      GearRatiosData(
+        ratios: ratios,
+        defaultGearIndex: defaultGearIndex,
+      ),
+    );
   }
 
-  Future<Result<void>> writeGearRatios(List<double> ratios) async {
+  Future<Result<void>> writeGearRatios(GearRatiosData data) async {
     final mtuResult =
         await _bluetooth.requestMtu(buttonDeviceId, mtu: _gearRatioWriteMtu);
     if (mtuResult.isErr()) {
@@ -93,12 +113,16 @@ class ShifterService {
           'Could not request MTU before writing gear ratios: ${mtuResult.unwrapErr()}');
     }
 
-    final payload = List<int>.filled(_gearRatioSlots, 0, growable: false);
+    final payload =
+        List<int>.filled(_gearRatioPayloadBytes, 0, growable: false);
+    final ratios = data.ratios;
     final limit =
         ratios.length < _gearRatioSlots ? ratios.length : _gearRatioSlots;
     for (var i = 0; i < limit; i++) {
       payload[i] = _encodeGearRatio(ratios[i]);
     }
+    payload[_defaultGearIndexOffset] =
+        limit == 0 ? 0 : data.defaultGearIndex.clamp(0, limit - 1).toInt();
 
     return _bluetooth.writeCharacteristic(
       buttonDeviceId,
@@ -177,3 +201,13 @@ class ShifterService {
     return raw / 64.0;
   }
 }
+
+class GearRatiosData {
+  const GearRatiosData({
+    required this.ratios,
+    required this.defaultGearIndex,
+  });
+
+  final List<double> ratios;
+  final int defaultGearIndex;
+}
diff --git a/lib/widgets/gear_ratio_editor_card.dart b/lib/widgets/gear_ratio_editor_card.dart
index 49ebc47..b77051e 100644
--- a/lib/widgets/gear_ratio_editor_card.dart
+++ b/lib/widgets/gear_ratio_editor_card.dart
@@ -17,6 +17,7 @@ class GearRatioPreset {
 class GearRatioEditorCard extends StatefulWidget {
   const GearRatioEditorCard({
     required this.ratios,
+    required this.defaultGearIndex,
     required this.isLoading,
     required this.onSave,
     required this.presets,
@@ -26,8 +27,10 @@ class GearRatioEditorCard extends StatefulWidget {
   });
 
   final List<double> ratios;
+  final int defaultGearIndex;
   final bool isLoading;
-  final Future<String?> Function(List<double> ratios) onSave;
+  final Future<String?> Function(List<double> ratios, int defaultGearIndex)
+      onSave;
   final List<GearRatioPreset> presets;
   final String? errorText;
   final VoidCallback? onRetry;
@@ -43,6 +46,13 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
   static const double _sliderPivotV = 1.00;
   static const Duration _animDuration = Duration(milliseconds: 280);
   static const Curve _animCurve = Cubic(0.2, 0.8, 0.2, 1.0);
+  static const int _maxGears = 32;
+  static const double _inlineAddRadius = 24;
+  static const double _editorTileOverlap = 20;
+
+  double get _inlineAddEdgeOffset => _inlineAddRadius + 2;
+
+  double get _editorTilesTopInset => _inlineAddEdgeOffset + _inlineAddRadius;
 
   bool _isExpanded = false;
   bool _isEditing = false;
@@ -54,20 +64,34 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
 
   List<double> _committed = const [];
   List<double> _draft = const [];
+  int _committedDefaultGearIndex = 0;
+  int _draftDefaultGearIndex = 0;
 
   @override
   void initState() {
     super.initState();
     _committed = List<double>.from(widget.ratios);
     _draft = List<double>.from(widget.ratios);
+    _committedDefaultGearIndex = _normalizeDefaultIndex(
+      widget.defaultGearIndex,
+      _committed.length,
+    );
+    _draftDefaultGearIndex = _committedDefaultGearIndex;
   }
 
   @override
   void didUpdateWidget(covariant GearRatioEditorCard oldWidget) {
     super.didUpdateWidget(oldWidget);
-    if (!_isEditing && !_listEquals(oldWidget.ratios, widget.ratios)) {
+    if (!_isEditing &&
+        (!_listEquals(oldWidget.ratios, widget.ratios) ||
+            oldWidget.defaultGearIndex != widget.defaultGearIndex)) {
       _committed = List<double>.from(widget.ratios);
       _draft = List<double>.from(widget.ratios);
+      _committedDefaultGearIndex = _normalizeDefaultIndex(
+        widget.defaultGearIndex,
+        _committed.length,
+      );
+      _draftDefaultGearIndex = _committedDefaultGearIndex;
     }
   }
 
@@ -183,7 +207,11 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
               if (!_isExpanded && !_isEditing && _committed.isNotEmpty)
                 Padding(
                   padding: const EdgeInsets.fromLTRB(14, 0, 14, 10),
-                  child: _compactRatioStrip(context, _committed),
+                  child: _compactRatioStrip(
+                    context,
+                    _committed,
+                    defaultGearIndex: _committedDefaultGearIndex,
+                  ),
                 ),
               AnimatedSize(
                 duration: _animDuration,
@@ -197,7 +225,12 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
                           runSpacing: 8,
                           children: [
                             for (var i = 0; i < _committed.length; i++)
-                              _ratioChip(context, i + 1, _committed[i]),
+                              _ratioChip(
+                                context,
+                                i + 1,
+                                _committed[i],
+                                isDefault: i == _committedDefaultGearIndex,
+                              ),
                           ],
                         ),
                       )
@@ -280,17 +313,15 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
                     switchInCurve: _animCurve,
                     switchOutCurve: Curves.easeInCubic,
                     transitionBuilder: _snappyTransition,
-                    child: Wrap(
-                      key: ValueKey('editors-$_gearLayoutVersion'),
-                      spacing: 8,
-                      runSpacing: 8,
-                      children: [
-                        for (var i = 0; i < _draft.length; i++)
-                          KeyedSubtree(
-                            key: ValueKey('editor-${i + 1}'),
-                            child: _buildGearEditor(context, i),
-                          ),
-                      ],
+                    child: Padding(
+                      padding: EdgeInsets.only(
+                        top: _editorTilesTopInset,
+                      ),
+                      child: Column(
+                        key: ValueKey('editors-$_gearLayoutVersion'),
+                        crossAxisAlignment: CrossAxisAlignment.stretch,
+                        children: _buildEditableGearTiles(context),
+                      ),
                     ),
                   ),
                 ),
@@ -314,73 +345,307 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
     );
   }
 
-  Widget _buildGearEditor(BuildContext context, int index) {
-    final ratio = _draft[index];
-    final sliderValue = _valueToSlider(ratio);
-    return ConstrainedBox(
-      constraints: const BoxConstraints(minWidth: 230, maxWidth: 280),
-      child: Container(
-        padding: const EdgeInsets.fromLTRB(10, 8, 10, 4),
-        decoration: BoxDecoration(
-          borderRadius: BorderRadius.circular(12),
-          color: Theme.of(context).colorScheme.surface.withValues(alpha: 0.7),
-          border: Border.all(
-            color: Theme.of(context)
-                .colorScheme
-                .outlineVariant
-                .withValues(alpha: 0.6),
+  List<Widget> _buildEditableGearTiles(BuildContext context) {
+    if (_draft.isEmpty) {
+      return [_buildStandaloneAddGearButton(context)];
+    }
+
+    final widgets = <Widget>[];
+    for (var i = 0; i < _draft.length; i++) {
+      final editor = KeyedSubtree(
+        key: ValueKey('editor-${i + 1}'),
+        child: _buildGearEditor(context, i),
+      );
+      if (i == 0) {
+        widgets.add(editor);
+      } else {
+        widgets.add(
+          Transform.translate(
+            offset: Offset(0, -i * _editorTileOverlap),
+            child: editor,
           ),
-        ),
-        child: Column(
-          crossAxisAlignment: CrossAxisAlignment.start,
-          children: [
-            Row(
-              children: [
-                Text(
-                  'Gear ${index + 1}',
-                  style: const TextStyle(fontWeight: FontWeight.w600),
-                ),
-                const Spacer(),
-                InkWell(
-                  borderRadius: BorderRadius.circular(6),
-                  onTap: () => _editRatioText(index),
-                  child: Padding(
-                    padding:
-                        const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
-                    child: Text(
-                      ratio.toStringAsFixed(2),
-                      style: const TextStyle(
-                        fontSize: 15,
-                        fontWeight: FontWeight.w700,
-                      ),
-                    ),
-                  ),
-                ),
-              ],
-            ),
-            Slider(
-              min: 0,
-              max: 1,
-              value: sliderValue,
-              onChanged: (value) {
-                setState(() {
-                  _draft[index] = _quantizeRatio(_sliderToValue(value));
-                });
-              },
-              onChangeEnd: (_) {
-                setState(() {
-                  if (_sortAscending) {
-                    _sortDraft(animate: true);
-                  }
-                });
-              },
-            ),
-          ],
+        );
+      }
+    }
+    return widgets;
+  }
+
+  Widget _buildStandaloneAddGearButton(BuildContext context) {
+    final canAdd = _draft.length < _maxGears;
+    return SizedBox(
+      width: double.infinity,
+      height: 118,
+      child: Center(
+        child: _buildInlineAddButton(
+          context,
+          afterIndex: -1,
+          canAdd: canAdd,
         ),
       ),
     );
   }
 
+  Widget _buildInlineAddButton(
+    BuildContext context, {
+    required int afterIndex,
+    required bool canAdd,
+    String? tooltip,
+  }) {
+    final theme = Theme.of(context);
+    return Tooltip(
+      message: canAdd ? 'Add gear' : 'Maximum $_maxGears gears reached',
+      child: Material(
+        type: MaterialType.transparency,
+        child: Ink(
+          width: _inlineAddRadius * 2,
+          height: _inlineAddRadius * 2,
+          decoration: ShapeDecoration(
+            shape: CircleBorder(
+              side: BorderSide(
+                color: theme.colorScheme.outlineVariant.withValues(alpha: 0.8),
+              ),
+            ),
+            color: theme.colorScheme.surface,
+            shadows: [
+              BoxShadow(
+                blurRadius: 12,
+                spreadRadius: 1,
+                color: Colors.black.withValues(alpha: 0.12),
+              ),
+            ],
+          ),
+          child: IconButton(
+            onPressed: canAdd ? () => _insertGearAfter(afterIndex) : null,
+            icon: const Icon(Icons.add),
+            iconSize: 22,
+            splashRadius: _inlineAddRadius,
+            tooltip: canAdd ? tooltip ?? 'Add gear' : null,
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildGearEditor(BuildContext context, int index) {
+    final theme = Theme.of(context);
+    final canAdd = _draft.length < _maxGears;
+    final ratio = _draft[index];
+    final sliderValue = _valueToSlider(ratio);
+    final isDefault = index == _draftDefaultGearIndex;
+    final borderColor = isDefault
+        ? theme.colorScheme.primary
+        : theme.colorScheme.outlineVariant.withValues(alpha: 0.6);
+    return Stack(
+      children: [
+        Padding(
+          padding: EdgeInsets.only(
+            right: _inlineAddEdgeOffset,
+            top: index == 0 ? _inlineAddEdgeOffset : 0,
+            bottom: _inlineAddEdgeOffset,
+          ),
+          child: ClipPath(
+            clipper: _GearEditorNotchClipper(
+              topNotchRadius: _inlineAddRadius + 2,
+              bottomNotchRadius: _inlineAddRadius + 2,
+            ),
+            child: Material(
+              color: theme.colorScheme.surface.withValues(alpha: 0.7),
+              borderRadius: BorderRadius.circular(12),
+              child: InkWell(
+                borderRadius: BorderRadius.circular(12),
+                onTap: () => _setDefaultGear(index),
+                child: Container(
+                  padding: const EdgeInsets.fromLTRB(10, 8, 10, 4),
+                  decoration: BoxDecoration(
+                    borderRadius: BorderRadius.circular(12),
+                    border: Border.all(
+                      color: borderColor,
+                      width: isDefault ? 1.6 : 1,
+                    ),
+                  ),
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Row(
+                        children: [
+                          Text(
+                            'Gear ${index + 1}',
+                            style: const TextStyle(fontWeight: FontWeight.w600),
+                          ),
+                          const SizedBox(width: 8),
+                          if (isDefault)
+                            Container(
+                              padding: const EdgeInsets.symmetric(
+                                horizontal: 8,
+                                vertical: 2,
+                              ),
+                              decoration: BoxDecoration(
+                                borderRadius: BorderRadius.circular(999),
+                                color: theme.colorScheme.primaryContainer,
+                                border: Border.all(
+                                  color: theme.colorScheme.primary.withValues(
+                                    alpha: 0.65,
+                                  ),
+                                ),
+                              ),
+                              child: Text(
+                                'default',
+                                style: theme.textTheme.labelSmall?.copyWith(
+                                  color: theme.colorScheme.onPrimaryContainer,
+                                  fontWeight: FontWeight.w700,
+                                ),
+                              ),
+                            ),
+                          const Spacer(),
+                          IconButton(
+                            visualDensity: VisualDensity.compact,
+                            tooltip: 'Delete gear',
+                            onPressed: () => _deleteGear(index),
+                            icon: const Icon(Icons.delete_outline),
+                          ),
+                          InkWell(
+                            borderRadius: BorderRadius.circular(6),
+                            onTap: () => _editRatioText(index),
+                            child: Padding(
+                              padding: const EdgeInsets.symmetric(
+                                horizontal: 8,
+                                vertical: 4,
+                              ),
+                              child: Text(
+                                ratio.toStringAsFixed(2),
+                                style: const TextStyle(
+                                  fontSize: 15,
+                                  fontWeight: FontWeight.w700,
+                                ),
+                              ),
+                            ),
+                          ),
+                        ],
+                      ),
+                      Slider(
+                        min: 0,
+                        max: 1,
+                        value: sliderValue,
+                        onChanged: (value) {
+                          setState(() {
+                            _draft[index] =
+                                _quantizeRatio(_sliderToValue(value));
+                          });
+                        },
+                        onChangeEnd: (_) {
+                          setState(() {
+                            if (_sortAscending) {
+                              _sortDraft(animate: true);
+                            }
+                          });
+                        },
+                      ),
+                    ],
+                  ),
+                ),
+              ),
+            ),
+          ),
+        ),
+        if (index == 0)
+          Positioned(
+            top: 0,
+            right: 0,
+            child: _buildInlineAddButton(
+              context,
+              afterIndex: index - 1,
+              canAdd: canAdd,
+              tooltip: 'Insert gear before',
+            ),
+          ),
+        Positioned(
+          bottom: 0,
+          right: 0,
+          child: _buildInlineAddButton(
+            context,
+            afterIndex: index,
+            canAdd: canAdd,
+            tooltip: 'Insert gear after',
+          ),
+        ),
+      ],
+    );
+  }
+
+  void _insertGearAfter(int index) {
+    if (_draft.length >= _maxGears) {
+      return;
+    }
+    final insertIndex = (index + 1).clamp(0, _draft.length);
+    final newRatio = _nextInsertedRatio(insertIndex);
+
+    setState(() {
+      final next = List<double>.from(_draft)..insert(insertIndex, newRatio);
+      _draft = next;
+      if (insertIndex <= _draftDefaultGearIndex) {
+        _draftDefaultGearIndex += 1;
+      }
+      _draftDefaultGearIndex = _normalizeDefaultIndex(
+        _draftDefaultGearIndex,
+        _draft.length,
+      );
+      if (_sortAscending) {
+        _sortDraft(animate: true);
+      } else {
+        _gearLayoutVersion++;
+      }
+      _stretchBase = null;
+    });
+  }
+
+  void _deleteGear(int index) {
+    if (_draft.isEmpty || index < 0 || index >= _draft.length) {
+      return;
+    }
+
+    setState(() {
+      final next = List<double>.from(_draft)..removeAt(index);
+      _draft = next;
+
+      if (_draft.isEmpty) {
+        _draftDefaultGearIndex = 0;
+      } else if (index < _draftDefaultGearIndex) {
+        _draftDefaultGearIndex -= 1;
+      } else if (index == _draftDefaultGearIndex) {
+        _draftDefaultGearIndex = index.clamp(0, _draft.length - 1);
+      }
+
+      _draftDefaultGearIndex = _normalizeDefaultIndex(
+        _draftDefaultGearIndex,
+        _draft.length,
+      );
+      _gearLayoutVersion++;
+      _stretchBase = null;
+    });
+  }
+
+  void _setDefaultGear(int index) {
+    if (index < 0 || index >= _draft.length) {
+      return;
+    }
+    setState(() {
+      _draftDefaultGearIndex = index;
+    });
+  }
+
+  double _nextInsertedRatio(int insertIndex) {
+    if (_draft.isEmpty) {
+      return _quantizeRatio(1.0);
+    }
+    if (insertIndex <= 0) {
+      return _quantizeRatio(_draft.first * 0.9);
+    }
+    if (insertIndex >= _draft.length) {
+      return _quantizeRatio(_draft.last * 1.1);
+    }
+    return _quantizeRatio((_draft[insertIndex - 1] + _draft[insertIndex]) / 2);
+  }
+
   Future<void> _editRatioText(int index) async {
     final controller = TextEditingController(
       text: _draft[index].toStringAsFixed(2),
@@ -493,6 +758,7 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
 
     setState(() {
       _draft = selected.ratios.map(_quantizeRatio).toList(growable: false);
+      _draftDefaultGearIndex = _normalizeDefaultIndex(0, _draft.length);
       if (_sortAscending) {
         _sortDraft(animate: true);
       }
@@ -500,11 +766,14 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
   }
 
   void _sortDraft({bool animate = false}) {
-    final sorted = _sorted(_draft);
-    if (animate && !_listEquals(_draft, sorted)) {
+    final sorted = _sortedWithDefault(_draft, _draftDefaultGearIndex);
+    final sortedValues = sorted.$1;
+    final sortedDefaultIndex = sorted.$2;
+    if (animate && !_listEquals(_draft, sortedValues)) {
       _gearLayoutVersion++;
     }
-    _draft = sorted;
+    _draft = sortedValues;
+    _draftDefaultGearIndex = sortedDefaultIndex;
   }
 
   void _enterEditMode() {
@@ -514,6 +783,10 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
       _stretchFactor = 1.0;
       _stretchBase = null;
       _draft = List<double>.from(_committed);
+      _draftDefaultGearIndex = _normalizeDefaultIndex(
+        _committedDefaultGearIndex,
+        _draft.length,
+      );
     });
   }
 
@@ -521,6 +794,10 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
     setState(() {
       _isEditing = false;
       _draft = List<double>.from(_committed);
+      _draftDefaultGearIndex = _normalizeDefaultIndex(
+        _committedDefaultGearIndex,
+        _draft.length,
+      );
       _stretchFactor = 1.0;
       _stretchBase = null;
     });
@@ -531,7 +808,10 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
       _isSaving = true;
     });
 
-    final message = await widget.onSave(List<double>.from(_draft));
+    final message = await widget.onSave(
+      List<double>.from(_draft),
+      _normalizeDefaultIndex(_draftDefaultGearIndex, _draft.length),
+    );
     if (!mounted) {
       return;
     }
@@ -540,6 +820,10 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
       _isSaving = false;
       if (message == null) {
         _committed = List<double>.from(_draft);
+        _committedDefaultGearIndex = _normalizeDefaultIndex(
+          _draftDefaultGearIndex,
+          _committed.length,
+        );
         _isEditing = false;
       }
     });
@@ -551,7 +835,12 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
     }
   }
 
-  Widget _ratioChip(BuildContext context, int gear, double ratio) {
+  Widget _ratioChip(
+    BuildContext context,
+    int gear,
+    double ratio, {
+    bool isDefault = false,
+  }) {
     final theme = Theme.of(context);
     return Container(
       padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
@@ -559,10 +848,17 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
         borderRadius: BorderRadius.circular(999),
         color: theme.colorScheme.surface.withValues(alpha: 0.7),
         border: Border.all(
-          color: theme.colorScheme.outlineVariant.withValues(alpha: 0.6),
+          color: isDefault
+              ? theme.colorScheme.primary
+              : theme.colorScheme.outlineVariant.withValues(alpha: 0.6),
+          width: isDefault ? 1.4 : 1,
         ),
       ),
-      child: Text('G$gear  ${ratio.toStringAsFixed(2)}'),
+      child: Text(
+        isDefault
+            ? 'G$gear  ${ratio.toStringAsFixed(2)}  default'
+            : 'G$gear  ${ratio.toStringAsFixed(2)}',
+      ),
     );
   }
 
@@ -570,6 +866,7 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
     BuildContext context,
     List<double> ratios, {
     bool showGearLabel = true,
+    int? defaultGearIndex,
   }) {
     final theme = Theme.of(context);
     return SizedBox(
@@ -588,13 +885,18 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
                     borderRadius: BorderRadius.circular(999),
                     color: theme.colorScheme.surface.withValues(alpha: 0.7),
                     border: Border.all(
-                      color: theme.colorScheme.outlineVariant
-                          .withValues(alpha: 0.55),
+                      color: i == defaultGearIndex
+                          ? theme.colorScheme.primary
+                          : theme.colorScheme.outlineVariant
+                              .withValues(alpha: 0.55),
+                      width: i == defaultGearIndex ? 1.3 : 1,
                     ),
                   ),
                   child: Text(
                     showGearLabel
-                        ? 'G${i + 1} ${ratios[i].toStringAsFixed(2)}'
+                        ? (i == defaultGearIndex
+                            ? 'G${i + 1} ${ratios[i].toStringAsFixed(2)} default'
+                            : 'G${i + 1} ${ratios[i].toStringAsFixed(2)}')
                         : ratios[i].toStringAsFixed(2),
                     style: theme.textTheme.bodySmall?.copyWith(
                       fontWeight: FontWeight.w600,
@@ -613,9 +915,34 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
     return ((clamped * 64).round() / 64.0).clamp(_sliderMin, _sliderMax);
   }
 
-  List<double> _sorted(List<double> values) {
-    final out = List<double>.from(values)..sort();
-    return out;
+  (List<double>, int) _sortedWithDefault(
+      List<double> values, int defaultIndex) {
+    final normalizedDefault =
+        _normalizeDefaultIndex(defaultIndex, values.length);
+    final decorated = List<_DraftGearEntry>.generate(
+      values.length,
+      (i) => _DraftGearEntry(
+        ratio: values[i],
+        isDefault: i == normalizedDefault,
+      ),
+      growable: false,
+    )..sort((a, b) => a.ratio.compareTo(b.ratio));
+
+    final sortedValues = decorated.map((entry) => entry.ratio).toList(
+          growable: false,
+        );
+    final sortedDefaultIndex = decorated.indexWhere((entry) => entry.isDefault);
+    return (
+      sortedValues,
+      _normalizeDefaultIndex(sortedDefaultIndex, sortedValues.length),
+    );
+  }
+
+  int _normalizeDefaultIndex(int index, int length) {
+    if (length <= 0) {
+      return 0;
+    }
+    return index.clamp(0, length - 1).toInt();
   }
 
   bool _listEquals(List<double> a, List<double> b) {
@@ -661,6 +988,69 @@ class _GearRatioEditorCardState extends State<GearRatioEditorCard> {
   }
 }
 
+class _DraftGearEntry {
+  const _DraftGearEntry({required this.ratio, required this.isDefault});
+
+  final double ratio;
+  final bool isDefault;
+}
+
+class _GearEditorNotchClipper extends CustomClipper<Path> {
+  const _GearEditorNotchClipper({
+    required this.topNotchRadius,
+    required this.bottomNotchRadius,
+  });
+
+  final double topNotchRadius;
+  final double bottomNotchRadius;
+
+  @override
+  Path getClip(Size size) {
+    final base = Path()
+      ..addRRect(
+        RRect.fromRectAndRadius(
+          Offset.zero & size,
+          const Radius.circular(12),
+        ),
+      );
+
+    if (topNotchRadius <= 0 && bottomNotchRadius <= 0) {
+      return base;
+    }
+
+    var clipped = base;
+    if (topNotchRadius > 0) {
+      final topNotch = Path()
+        ..addOval(
+          Rect.fromCircle(
+            center: Offset(size.width, 0),
+            radius: topNotchRadius,
+          ),
+        );
+      clipped = Path.combine(PathOperation.difference, clipped, topNotch);
+    }
+
+    if (bottomNotchRadius > 0) {
+      final bottomNotch = Path()
+        ..addOval(
+          Rect.fromCircle(
+            center: Offset(size.width, size.height),
+            radius: bottomNotchRadius,
+          ),
+        );
+      clipped = Path.combine(PathOperation.difference, clipped, bottomNotch);
+    }
+
+    return clipped;
+  }
+
+  @override
+  bool shouldReclip(covariant _GearEditorNotchClipper oldClipper) {
+    return oldClipper.topNotchRadius != topNotchRadius ||
+        oldClipper.bottomNotchRadius != bottomNotchRadius;
+  }
+}
+
 class _GearRatioGraph extends StatelessWidget {
   const _GearRatioGraph({required this.ratios, required this.compact});