MEGABOBRA: Bosch Smart System Derestriction for Rim Magnet - DIY Project with Support

[littleleye]

Looks amazing, very professional. Keep up the good work!

 

[AlumiPro]

I’m ready to send a payment as soon as you send a bill.

 

[mav75]

Amazing can't wait!

 

[przemass]

I'm also interested, please contact with me

 

[Spagnol]

Finally, most of the components turned up for the first batch of Megabobras. Still waiting on the Bosch LPP cables, but the remaining parts are assembled and are waiting to drop the cables in.

There have been a few upgrades since the original tutorial. These models all now run on the RP2040 boards; more than 10x faster clock speed and less than half the size than the original Arduino Nanos. These devices now also feature the Setup mode jumper cable to assist with electromagnet placement.

Once the Bosch LPP cables are installed, these will be sealed up in heatshrink end caps. I'm finalising a manual to assist with setup and operation - this will be ready by the time the cables arrive.

Now is a good time to remind everyone that these devices, as with any which lift the assistance speed, are only for use on private property, may increase wear on your drive train and may void the warranty on your motor.

I'll begin reaching out to everyone directly by direct message in the order they expressed interest once the Bosch LPP cables have arrived.

View attachment 120859 View attachment 120860 View attachment 120861

Looks good . Looking forward to pay and receive mine

 

[bail0ut]

Hi @megabobra
Please add me to your list and contact me

 

[Canyon]

I've spent some time sourcing components that would be needed for this project and worked out some costing.

This would comprise all necessary components to install the Megabobra to replace the rim magnet, including the genuine Bosch LPP cable to plug into the motor:

• Arduino loaded with Megabobra code and additional electronic components soldered in place
  • Covered with double-wall heat shrink for protection
• Waterproof reed switch
• Hand wound electromagnet coil
• All wiring in place and secured
• Light weight plugs between components to assist with install
• Bosch LPP cable
• Magnet for disc rotor
• Some strips of double-sided tape for reed switch and coil
• Short install guide to assist with connection/placement/troubleshooting

Total cost per device would be 99USD/80GBP/90EUR or equivalent in your favourite currency. This include shipping worldwide. Payment by Paypal.

Now to manage expectations, this isn't a commercial product. The finish isn't going to be as nice as you might get in a product off the shelf simply because I don't have access to the customisation that large scale affords. For example, where the big companies might have a reed switch with custom-length cable for the perfect fit, I'll instead need to extend that cable myself to make it work. However, all builds would be carefully assembled and tested prior to going out, and I'd be happy to replace any that are not working.

The idea with this is that you unpack the device, feed the reed switch through the frame, position the coil, plug in the LPP and get going ASAP - probably an hour's install on the first run giving it's pretty tight around the motor on some frames?

IMPORTANT
Running from the LPP on the motor requires that port to be activated. If it's not already activated, you'll need to have your local dealer enable it. That's done through the USBC connection on the smart controller on your bars.

There's no integration with the Kiox display, so the display will work as before though all metrics will be offset by the multiplier value you choose. I've been running my device on Bosch's latest firmware version, but critically, ensure you're not using GPS when running the device - I've got no confirmation on this, but I would expect detection if GPS speed doesn't agree with sensor reported speed.

Assuming there's still interest now that you know the pricing, please like/reply to this if you're happy to go ahead so I can understand numbers for the components I'll need to bring in. Time frame wise, it would probably be 4-6 weeks before I can get any devices out due to the lead time with these required components. Ordering just be through Private Message where you can specify the required multiplier and wheel circumference for your setup.

Tagging a few who had expressed interest already: @littleleye @Lavouch @dlatch @timothe @Zave @przemass

I am also interested but how do I know if the LPP is active? I'm new on the forum and can't find it right away. grtz

 

[megabobra]

I am also interested but how do I know if the LPP is active? I'm new on the forum and can't find it right away. grtz

Hi Canyon,
I believe the LPP is disabled by default, so safe to say that if you haven't requested your dealer to turn it on, it's off. To confirm you could carefully probe the port with a multimeter and check for 12v, but it's very small in there. Best just to approach your dealer and ask for them to enable it to be safe.

 

[megabobra]

Apologies for the silence on the build of these devices lately, still waiting on the Bosch cables. Once they arrive it's a quick final point to solder them in place; all other components are completed.

Once complete, I'll post some final photos and begin reaching out to those first ten users by direct message to grab postal details. As a heads up, I also need your wheel circumference and, more importantly, your choice of multiplier to be initially programmed. This can always be changed in future with the code in the original tutorial.

Remember, the larger the multiplier, the greater the motor’s power consumption, the more likely the derestriction will be detected! Pedalling assisted at 50kph will draw significantly more power than at 25kph. Overtime, the motor may determine that power consumption to be unrealistic for the reported speed and return a detection error. Always use the lowest multiplier you can to reduce this risk. Below are some sample multipliers, showing their effect on max speed. The value you select doesn't have to be one listed but I suggest not going above 2.0 for the reason above.

Standard Max Speed​	Multiplier​	New Max Speed​
20 mph​	1.40​	28 mph​
20 mph​	1.60​	32 mph​
20 mph​	1.80​	36 mph​
25 kph​	1.40​	35 kph​
25 kph​	1.60​	40 kph​
25 kph​	1.80​	45 kph​
32 kph​	1.25​	40 kph​
32 kph​	1.40​	45 kph​
32 kph​	1.55​	50 kph​

 

[scm007]

I'm interested.

 

[Canyon]

Hi Canyon,
I believe the LPP is disabled by default, so safe to say that if you haven't requested your dealer to turn it on, it's off. To confirm you could carefully probe the port with a multimeter and check for 12v, but it's very small in there. Best just to approach your dealer and ask for them to enable it to be safe.

Thx Megabobra.
The Canyon service center says...This option is not provided in the software profile of the bike, so it cannot be activated afterwards. So I have to look for another solution.

 

[AlumiPro]

I’m waiting to receive my new Crestline RS 75/50, which will be my first Bosch powered ebike. (Currently ridding a Brose) I’m also in the first batch of 10, for this tune. Do I need to confirm this will work on the Crestline Bosch smart CX-Race motor, with rim magnet?….I was just figuring it would.

 

[megabobra]

Thx Megabobra.
The Canyon service center says...This option is not provided in the software profile of the bike, so it cannot be activated afterwards. So I have to look for another solution.

What a strange response from Canyon... I'd be checking at another dealer if you can, perhaps a Trek if there's one local to you? Otherwise, you could instead request one of the light ports to be activated, or the HPP (high power port). Same cable I believe?

 

[megabobra]

I’m waiting to receive my new Crestline RS 75/50, which will be my first Bosch powered ebike. (Currently ridding a Brose) I’m also in the first batch of 10, for this tune. Do I need to confirm this will work on the Crestline Bosch smart CX-Race motor, with rim magnet?….I was just figuring it would.

To be honest I'm not aware of anyone who has run it on the Race specifically, but I suspect the process will be exactly the same

 

[AlumiPro]

To be honest I'm not aware of anyone who has run it on the Race specifically, but I suspect the process will be exactly the same

So the motor just needs one of the unused ports to have power? And this may need to be turned on by Bosch?

 

[megabobra]

So the motor just needs one of the unused ports to have power? And this may need to be turned on by Bosch?

Exactly right yes; LPP, lights, HPP, doesn't really matter. I think with the lights ports there may be some built in logic to conserve the last few percent of battery power.

 

[AlumiPro]

Exactly right yes; LPP, lights, HPP, doesn't really matter. I think with the lights ports there may be some built in logic to conserve the last few percent of battery power.

Ok. One of these ports may already have power turned on, If I’m lucky?…. Since my Crestline will be shipped to me. Not picking it up from a Bosch dealer.

 

[megabobra]

Fingers crossed! Some bikes come with a small headlight/tail light, so they would turned on by default.

 

[megabobra]

Alright guys, Bosch cables turned up - now things can get going! I'll get messages out this evening. Photo below of a completed device mounted to its shipping board, along with the front cover of the user guide.

 

[littleleye]

Great! Can't wait to receive, mount and try out the MEGABOBRA! Looking forward to your message, I have al the details you need ready.

 

[AlumiPro]

Alright guys, Bosch cables turned up - now things can get going! I'll get messages out this evening. Photo below of a completed device mounted to its shipping board, along with the front cover of the user guide.

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Message sent.
How does the magnet stay in place?
Will it mount to Magura MDR-P rotors?

 

[mav75]

Hi all . I'm just wondering what is the best reason to give to the Bosch dealer when requesting LLP to be turned off ? Other than mind your own I'm sure you know how jobs worthy some guys can be eh ?

 

[Canyon]

Hi all . I'm just wondering what is the best reason to give to the Bosch dealer when requesting LLP to be turned off ? Other than mind your own I'm sure you know how jobs worthy some guys can be eh ?

you can say it is for a gps tracker. Tomorrow I will try to activate mine

 

[Mars2]

PAYPAL sent

 

[megabobra]

Hi all . I'm just wondering what is the best reason to give to the Bosch dealer when requesting LLP to be turned off ? Other than mind your own I'm sure you know how jobs worthy some guys can be eh ?

I requested it be turned on for a GPS tracking device that needed 12v. Or otherwise, you could mention that it's for a self-built shockwiz type device to help you tune your suspension?

 

[megabobra]

Message sent.
How does the magnet stay in place?
Will it mount to Magura MDR-P rotors?

The electromagnet is mounted inside the frame, either to the motor casing or the inner wall of the frame itself, just with some double-sided tape. It's light enough (only a few grams) that it doesn't need anything much to hold it in place.

The rotor magnet is just held to the brake rotor by its own magnetic force. I've had mine stuck on the side of a Sram HS2 rotor since day one and it hasn't moved. For some two-piece rotors that have central aluminium arms, you could either use glue or tape to attach the rotor. Or otherwise, you could use a spoke magnet!

 

[megabobra]

First five devices going out today. I'll reach out to each of you individually with tracking numbers.

 

[AlumiPro]

you can say it is for a gps tracker. Tomorrow I will try to activate mine

Any luck activating?

 

[manu.w]

Hello!
New to this forum, but an old user of a similar "man in the middle" pulse generator on a classic reed switch system.
About the (arduino) code, is there a github repo for sharing the magnetic pulse generation?
Thanks

 

[megabobra]

Hello!
New to this forum, but an old user of a similar "man in the middle" pulse generator on a classic reed switch system.
About the (arduino) code, is there a github repo for sharing the magnetic pulse generation?
Thanks

Hi Manu,
There's no github, but you can find the code in the tutorial post, linked in the first post in this thread. I've attached a copy here as well that's going on the Seeeduino devices I'm posting out.
Hope this helps!