rockfordhayes
New member
In a quest to find a security solution for the 4-Button GPS Cradle on my 2013 RT (Camhead), I ended up with a hybrid solution. By “hybrid” I mean a combination of an off-the-shelf product, along with some minor fabrication. Here’s the story:
The solution begins with a product called Zumo Lock. This is a quality locking mechanism produced by a company of the same name, in the Netherlands. They actually make three different versions for three distinct Garmin Zumo models: the 660, 59x, and 3xx. I ordered the 59x version. (The NUVI 660 is most closely related to the BMW GPS units. But in examining the images of the locking units, I determined the 59x version was best suited to the modifications I had in mind.)
Here’s a photo of the lock, including a blue RAM Mount accessory w/knob. You can order with or without this locking accessory; it is not needed for our application -
This lock is designed to install against the back of the Cradle. When engaged by the barrel key, a small stainless hasp comes up around the plastic release button – preventing you from being able to push it. It’s fairly straight forward and easy to install. HOWEVER, while I am certain it works perfectly for the Garmin units its designed for, it WILL NOT WORK on the BMW 4-button Cradle – at least, not out of the box – the locking hasp can’t engage the button. With the Zumo Lock 59x version, the hasp misses the button by about 1/4 inch. Additionally, the mounting holes are too small, and the hasp makes inappropriate contact with the back side of the Nav.
To remedy that, I cooked up a solution that involves a bit of modest machining to the locking unit, and drilling a very small, precise, hole into the end of the plastic release button – so it could accept an extension screw. To accomplish the drilling, I had to disassemble the cradle.
Here are the details for these two procedures:
1. There are two modifications to the locking mechanism. First, the 4 mounting holes need to be enlarged to accommodate the four OEM steal spacers that are located at the back of the Cradle. I used a 13/64" bit to get the job done, then carefully de-burred the holes. These plates are made of stainless steel, which has been black powder coated – so even after the holes have been drilled out there is no chance they will rust or corrode. Second, the outer arc of the stainless hasp needs to be carefully ground down so it clears the back side of the GPS unit – removal of just 1mm of material is adequate. Otherwise, the hasp rubs right up against the GPS. I de-burred the hasp after grinding, and used a small drop of blue locktite when reinstalling it on the lock mechanism. (One may also have to fine tune the opening of the hasp, depending on fitment.)
2. There is just one modification to the Cradle, but it is a critical one. I drilled a 1/16” hole about 1/2 inch deep into the end of the plastic release button. To do so successfully, I had to remove the button from the Cradle. It’s not very difficult to do, but disassembly does require some patience and care. I removed the numerous tiny screws on the rear of the Cradle, and carefully opened the back. I took great care to ensure the whole thing didn’t fly apart. The button itself was still held in place by the actuator spring. I was careful to prevent the spring from flying off. I used a machinist vice to secure the button vertically, and used my drill press to precisely make the hole. Then I reassembled the Cradle.
I then installed the locking mechanism as part of reattaching the Cradle to its mount, using some longer 40 mm stainless screws and four small 6.35 mm nylon spacers. The longer screws and spacers help move the Cradle/Lock assembly back away from the windscreen - to prevent contact when the screen is fully lowered.
For that tiny hole I just made in the button, I bought a very small stainless steel screw w/ washer & nut. I found this hardware at one of the larger ACE stores in my area – they have an expansive threaded fastener selection. The screw itself is a Slotted Pan Head 1-72 x 1/2”. The washer is a No. 3 size (two sizes larger than screw, to provide a larger outer surface area). I put the washer and nut on the screw, used a miniscule amount of blue locktite, and tightened the nut. Finally, I inserted this screw into the button (it is pretty much self-threading) and adjusted it to properly engage with the locking mechanism.
Here are a few photos of the completed project-
Unlocked
Locked
Front
Behind
The Zumo Lock is not cheap – $83.43 US shipped, when I bought mine in March. And, this is certainly not a bullet proof security solution – especially for a $900 piece of hi-tech roughly the size of a bar of soap. But, it does allow me to leave the GPS on the bike long enough for a restroom break, etc. I still remove and secure the Nav VI if I’m gonna be away from the bike for more than a few minutes.
Zumo Lock Website: https://www.zumolock.com/index.php/en/
Anyway, I hope other’s find this info useful…
The solution begins with a product called Zumo Lock. This is a quality locking mechanism produced by a company of the same name, in the Netherlands. They actually make three different versions for three distinct Garmin Zumo models: the 660, 59x, and 3xx. I ordered the 59x version. (The NUVI 660 is most closely related to the BMW GPS units. But in examining the images of the locking units, I determined the 59x version was best suited to the modifications I had in mind.)
Here’s a photo of the lock, including a blue RAM Mount accessory w/knob. You can order with or without this locking accessory; it is not needed for our application -
This lock is designed to install against the back of the Cradle. When engaged by the barrel key, a small stainless hasp comes up around the plastic release button – preventing you from being able to push it. It’s fairly straight forward and easy to install. HOWEVER, while I am certain it works perfectly for the Garmin units its designed for, it WILL NOT WORK on the BMW 4-button Cradle – at least, not out of the box – the locking hasp can’t engage the button. With the Zumo Lock 59x version, the hasp misses the button by about 1/4 inch. Additionally, the mounting holes are too small, and the hasp makes inappropriate contact with the back side of the Nav.
To remedy that, I cooked up a solution that involves a bit of modest machining to the locking unit, and drilling a very small, precise, hole into the end of the plastic release button – so it could accept an extension screw. To accomplish the drilling, I had to disassemble the cradle.
Here are the details for these two procedures:
1. There are two modifications to the locking mechanism. First, the 4 mounting holes need to be enlarged to accommodate the four OEM steal spacers that are located at the back of the Cradle. I used a 13/64" bit to get the job done, then carefully de-burred the holes. These plates are made of stainless steel, which has been black powder coated – so even after the holes have been drilled out there is no chance they will rust or corrode. Second, the outer arc of the stainless hasp needs to be carefully ground down so it clears the back side of the GPS unit – removal of just 1mm of material is adequate. Otherwise, the hasp rubs right up against the GPS. I de-burred the hasp after grinding, and used a small drop of blue locktite when reinstalling it on the lock mechanism. (One may also have to fine tune the opening of the hasp, depending on fitment.)
2. There is just one modification to the Cradle, but it is a critical one. I drilled a 1/16” hole about 1/2 inch deep into the end of the plastic release button. To do so successfully, I had to remove the button from the Cradle. It’s not very difficult to do, but disassembly does require some patience and care. I removed the numerous tiny screws on the rear of the Cradle, and carefully opened the back. I took great care to ensure the whole thing didn’t fly apart. The button itself was still held in place by the actuator spring. I was careful to prevent the spring from flying off. I used a machinist vice to secure the button vertically, and used my drill press to precisely make the hole. Then I reassembled the Cradle.
I then installed the locking mechanism as part of reattaching the Cradle to its mount, using some longer 40 mm stainless screws and four small 6.35 mm nylon spacers. The longer screws and spacers help move the Cradle/Lock assembly back away from the windscreen - to prevent contact when the screen is fully lowered.
For that tiny hole I just made in the button, I bought a very small stainless steel screw w/ washer & nut. I found this hardware at one of the larger ACE stores in my area – they have an expansive threaded fastener selection. The screw itself is a Slotted Pan Head 1-72 x 1/2”. The washer is a No. 3 size (two sizes larger than screw, to provide a larger outer surface area). I put the washer and nut on the screw, used a miniscule amount of blue locktite, and tightened the nut. Finally, I inserted this screw into the button (it is pretty much self-threading) and adjusted it to properly engage with the locking mechanism.
Here are a few photos of the completed project-
Unlocked
Locked
Front
Behind
The Zumo Lock is not cheap – $83.43 US shipped, when I bought mine in March. And, this is certainly not a bullet proof security solution – especially for a $900 piece of hi-tech roughly the size of a bar of soap. But, it does allow me to leave the GPS on the bike long enough for a restroom break, etc. I still remove and secure the Nav VI if I’m gonna be away from the bike for more than a few minutes.
Zumo Lock Website: https://www.zumolock.com/index.php/en/
Anyway, I hope other’s find this info useful…
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