A while back, I got a no-name CarPlay receiver for my motorcycle. It’s been working well. I like being able to see maps, to control the music, and to operate garage doors without getting my phone out of my pocket.

It has been mounted on my handlebars with a RAM mount. I really like RAM mounts, and have used them for many things on many motorcycles over the years. However, I don’t need to reposition this device, so the flexibility of the ball-and-socket arm system is wasted. The mount is also a bit bulky, which is awkward because the place I want it is basically right over my handlebar clamp.

A black plastic contraption is mounted on the handlebars of a motorcycle using RAM ball-and-socket joints

So let’s machine a new mount! The first step was taking off the original and measuring it. The only critical measurements are the placements of the bolts that hold the clamp on, so I used a flatbed scanner and a ruler to digitize it and took measurements off of that.

The factory clamp is black and shiny aluminum. It is mounted using four bolts and clamps the handlebars down to the front of the bike. A scan of the bottom of the bracket. The four bolt holes are visible, along with the semi-circle that holds the bar tubing. There is a ruler in the scan, marked in inches for some strange reason

Next, I modeled up a minimal version and 3D Printed it. It fit reasonably well, so it was time to design a real one.

A simplified version of the factory clamp next to the factory clamp. The simplified version is basically four bolt holes and a spacer bar. The simplified version does fit on the bike

The back of the unit is frustratingly not flat, which you may remember from the mount for the other bike. A complicated flat shape is screwed on to the back of a device. There are multiple cutouts to accommodate various things hanging off of the device

That meant I’d need a platform with some standoff. I realized that I’d want to be able to adjust the position of the GPS on the mount, so I designed in some slots. By tightening the screws that connect the GPS side, it would be locked into place against the handlebar side.

CAD model of clamp and platform with slots in the clamp

I 3D printed this to test, and quickly discovered the flaw… it is impossible to tighten the screws on one part after you’ve attached the other to it. Oops.

After some thought, I came up with a plan: the platform would screw onto the clamp from the front. This would require a third setup on the mill, but that’s not too painful. I printed a version of this using captured nuts and it worked fine.

The 3d printed clamp is now substantially blockier. There are two horizontal cutouts in the front of it that hold hex nuts A front/top view, showing the bolts attaching through the front

Finally, something worth machining! I did this on a Haas Super Mini mill at ACC. This went pretty smoothly. I used a new-to-me toolpath (“Flow”) to run a ball-nosed endmill along the curve that grabs the handlebar. It seems to have plenty of grip. I manually tapped the bolt holes in the front.

A shiny block of aluminum with four bolt holes and an extra hole in the middle. It has been machined to have a spiral pattern and the bolt holes in the front are visible in a recess On the bottom side of the part, a subtle scalloping is visible on the U-shaped spaces where the handlebar tube goes

I did leave the slots in the first version of the platform, so that I could find the optimal placement of the GPS front-to-back. Too far forward and it would make it hard to see the speedometer. Too far backward and it hits the keys.

The back of the device has a 3D printed platform with two slots. Four bolts hold the platform to the back. A ruler is measuring how far the bolts are from the bottom, sensibly in mm

The speedometer and the CarPlay unit are both lit up. The CarPlay unit is showing an image of a motorcycle.

I’ve been riding around with it for a few weeks and my handlebars haven’t fallen off, so… success!