Customizable Navigation Bar Holder / GPS Bar Clamp

A customizable two-piece navigation bar holder for motorcycle GPS, phone, tablet and DMD-style mounts.

This model is designed as a parametric OpenSCAD / MakerWorld Customizer file. You can adjust the bar diameter, clamp tolerance, block size, bolt spacing, nut pockets and corner radius directly in the MakerWorld customizer.

Key Features

• Fully customizable bar diameter
• Designed for navigation bars, GPS bars and handlebar-style mounting points
• Bar runs through the short side of the block
• Two-piece clamp design: front and back part
• Both parts are placed print-ready with the groove facing upward
• M4 bolt holes
• Optional M4 hex nut pockets in the back part
• Rounded corners
• Adjustable clamp undersize for a tighter or looser fit
• Suitable for common adventure motorcycle navigation bars

Common Diameter Examples

Recommended starting values:

•  BMW / adventure GPS bar: 
  • Bar_Diameter = 12.0
  • Clamp_Undersize = 0.30
  • Hardware
    • M4 Bolt 25mm
    • M4 nyloc nuts
• Some BMW navigation bars: 
  • Bar_Diameter = 16.0
  • Clamp_Undersize = 0.30
  • Hardware
    • M4 Bolt 30mm
    • M4 nyloc nuts

Always measure your own bar with calipers before printing. Small differences matter for clamp fit.

Important Assembly Note

Both parts are shown in print orientation with the bar groove facing upward.

For assembly:

1. Place the back part against the navigation bar.
2. Flip the front part over.
3. Put the front part over the bar.
4. Insert the M4 bolts.
5. Tighten gradually and evenly.

The two half-round grooves will clamp around the bar.

Parameters

Main customizer parameters:

Bar_Diameter

Nominal diameter of your motorcycle navigation bar.
 

Bar_Offset_X

Moves the bar groove left or right from the center of the block.
This is useful when the navigation bar needs to sit slightly off-center.
Default value: 0.0 mm

Range: -10 mm to +10 mm

Clamp_Undersize

Reduces the actual groove diameter for a tighter clamp.

Example: Bar_Diameter = 12.0 and Clamp_Undersize = 0.30 creates an effective 11.7 mm clamp.

Block_Length

Overall length of the clamp block.

Block_Width

Overall width of the clamp block.

Half_Thickness

Thickness of each half.

Set to 0 for automatic thickness.

Corner_Radius

Controls the rounded corners.

Bolt Parameters

Bolt_Size
Selects the bolt size used for the clamp.
Options: M3, M4, M5
The model automatically adjusts the bolt hole diameter and nut pocket size based on this setting.

Bolt_Clearance
Adds extra clearance to the selected bolt diameter.
Example:
Bolt_Size = M4
Bolt_Clearance = 0.5
This creates a 4.5 mm bolt hole.

Increase this value if your printer makes holes too tight.

Manual_Hole_Diameter
Manual override for the bolt hole diameter.
Set this value to 0 to use automatic hole sizing based on Bolt_Size and Bolt_Clearance.
Use this only if you want full manual control over the hole diameter.

Hole_Spacing_X
Horizontal spacing between the left and right bolt holes.
Measured center-to-center.

Hole_Spacing_Y
Vertical spacing between the upper and lower bolt holes.
Measured center-to-center.
Back Nut Pocket Parameters

Nut_Pockets
Enables or disables hexagonal nut pockets in the back part.
Options:
true
Adds hex nut pockets to the back part.
false
Creates normal through-holes only.

Nut_Pocket_Clearance
Adds extra clearance to the automatic nut pocket size.
Increase this value if your nuts are too tight.
Decrease this value if your nuts are too loose.

Manual_Nut_Flat_To_Flat
Manual override for the hex nut pocket size.
Measured flat-to-flat.
Set this value to 0 to use automatic sizing based on Bolt_Size and Nut_Pocket_Clearance.

Manual_Nut_Depth
Manual override for the hex nut pocket depth.
Set this value to 0 to use automatic depth based on Bolt_Size.
Increase this value if your nuts sit proud of the surface.
Advanced Parameters

Preview_Cutaway
Creates a cutaway preview to inspect the internal groove and holes.
Options: false

Normal printable model.

true

Cutaway preview mode.

Use false before exporting for printing.

Facet_Count

Controls the smoothness of circular features such as the bar groove, bolt holes and nut pockets.
Options: 32, 48, 64, 96, 128
Recommended value: 96

Higher values create smoother curves but may generate larger files.

Print Settings

Recommended material:

• PETG
• ASA
• ABS

• PETG-CF

   

Suggested settings:

• 4–6 walls/perimeters
• 40–60% infill
• 0.2 mm layer height
• Print both parts with the groove facing upward

Use supports only if your slicer requires them for the nut pockets

For motorcycle use, avoid PLA because heat and sunlight can deform the part.

Hardware

Recommended hardware:

• 4x M4 bolts
• 4x M4 nuts or nyloc nuts
• Optional washer under bolt heads
• Optional thin rubber strip or double-sided tape around the bar for extra grip

Disclaimer

This is a DIY 3D printed motorcycle accessory. Use at your own risk. Check fitment and strength before riding. Re-check bolt tightness after the first ride and inspect the part regularly for cracks or wear.

Credits

Created as a customizable navigation bar holder for motorcycle GPS / DMD-style mounting setups.