• Warning!!

    Riding a tuned or deristricted EMTB is not a trivial offence and can have serious legal consequences. Also, many manufacturers can detect the use of a tuning device or deristricting method and may decline a repair under warranty if it was modified from the intended original specification. Deristricting EMTB's can also add increased loads for motors and batteries. Riding above the local law limit may reclassify the bike as a low-powered bike, requiring insurance, registration and a number plate.

    Be aware of your local country laws. Many laws prohibit use of modified EMTB's. It is your responsibility to check local laws. Ignoring it, has potential implications to trail access, and risk of prosecution in the event of an accident.

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    We advise members great caution. EMTB Forums accepts no liability for any content or advice given here. 


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

manu.w

Member
Aug 5, 2023
94
40
belgium
Asked in two dealers if they would check with the Bosch Diagnostic Tool, both refused because I didn’t buy the bike from them!
What the f, so anti commercial , they could ask a few euros for it (their valuable time behind a pc)…
 

AlumiPro

Active member
May 1, 2023
211
170
California
I didn’t feel comfortable probing inside the tiny Bosch outlet ports so I cut the shrink tube back on the Megabobra so could easily meter the voltage at that point. With the Bosch turned on I am not getting any power(12v) from the LPP or HPP!….neither are turned on.

IMG_6374.jpeg
 

megabobra

Active member
Jul 24, 2022
264
267
Australia
I wouldn’t know……my bike isn’t sold in any stores, only online.
I’ll have to call the local bike shop that sells Trek 😬
I’ve heard it’s a royal pain to get a Bosch port powered on!

That's OK, I did the same when taking my Voima into a local Trek store. They asked some questions about why I wanted to turn on the LPP, but otherwise were happy to go ahead and do it once they'd done a training module to work out how to!
 

AlumiPro

Active member
May 1, 2023
211
170
California
That's OK, I did the same when taking my Voima into a local Trek store. They asked some questions about why I wanted to turn on the LPP, but otherwise were happy to go ahead and do it once they'd done a training module to work out how to!
So what was your reason for wanting the LPP turned on?
 

manu.w

Member
Aug 5, 2023
94
40
belgium
Alternative just ask then to activate the light ports, and if they ask you why 🤪, tell them whatever they want to hear…
 

Patcho

Member
Aug 28, 2023
7
2
Netherlands
Hello everyone, apologies for my "no knowledge".
I got a new cube STEREO HYBRID 140 HPC 2023 2 weeks ago. I'm assuming this bike also uses a magnet. If I use this module, will it go faster? Everywhere I look for a chip I read that people keep having problems with the bosch smart system, Thanks! :)
 
Last edited:

megabobra

Active member
Jul 24, 2022
264
267
Australia
Hello everyone, apologies for my "no knowledge".
I got a new cube STEREO HYBRID 140 HPC 2023 2 weeks ago. I'm assuming this bike also uses a magnet. If I use this module, will it go faster? Everywhere I look for a chip I read that people keep having problems with the bosch smart system, Thanks! :)
Hi Patcho, this device will increase the assistance speed on bosch gen4 motors with rim magnet. You'll need to confirm if your bike uses a rim magnet first, it'll be on the valve of the rear wheel. If so, then have a read through the tutorial linked in the first post and finally, post a photo of your completed megabobra!
 

Patcho

Member
Aug 28, 2023
7
2
Netherlands
Hi Patcho, this device will increase the assistance speed on bosch gen4 motors with rim magnet. You'll need to confirm if your bike uses a rim magnet first, it'll be on the valve of the rear wheel. If so, then have a read through the tutorial linked in the first post and finally, post a photo of your completed megabobra!
I think mine is not on the valve :(

csm_stereo_140_hybrid_my22_speed_sensor_kstich_desktop_22cb1e196e_2.jpg
 

tatane

Member
Jun 25, 2023
59
41
Southern France
"enable all the ports" might not be the best idea tbh ... enabling the lights ports (at least on the EU regulated ones) get the engine to keep a battery reserve for the lights in case you have to pedal back home in the night ... meaning you lose ~5-10% of your battery capacity to that, regardless of having any actual lights plugged in
 

AlumiPro

Active member
May 1, 2023
211
170
California
"enable all the ports" might not be the best idea tbh ... enabling the lights ports (at least on the EU regulated ones) get the engine to keep a battery reserve for the lights in case you have to pedal back home in the night ... meaning you lose ~5-10% of your battery capacity to that, regardless of having any actual lights plugged in
I’ve heard about that.
I just want the LPP turned on. But I want to walk in to the local Trek/Bosch dealer with the best possible response to why I want it turned on, on my non Trek bike……hoping they don’t just kick me out!
 

bail0ut

Member
Jul 31, 2023
7
9
UK
What are all the parts they enabled?
What was your reason you said to them for wanting to enable the parts? (Parts meaning: the Bosch outlet plugs?)
I simply asked for both lights and LPP ports to be enabled. They didn’t quiz me about the LPP use case.
Interestingly he also reset the service timer back to 365 days (the bike is two months old) which was nice but has now got my thinking what will I do this time next year when it’s flagging up a service.
 

Wart

New Member
Sep 3, 2023
1
0
Germany
For those who have been following the existing Derestricting bosch smart system thread, this will be old news, but I figured it be a good idea to branch the build of the Megabobra device into its own thread to manage questions without cluttering the existing topic.


Quick Refresher:

The Megabobra device is an arduino-based open source derestricter for the bosch smart system with rim magnet. It uses a small electromagnet to replace the rim magnet, allowing the existing speed limit to be lifted to a value of your choice. The build needs some soldering experience but nothing too complicated once your source the components.

I've put together a detailed build guide here.

Some FAQ:
  • YES it will disrupt your total trip distance and odometer, but it's a simple multiplication to get the true figures. ie reported trip distance * chosen multiplier = true trip distance.
  • YES it should work on setups without the rim sensor. Instead of positioning the elctromagnet against the motor case, position it against the speed sensor.
  • Total power usage when the magnet is firing is ~2.4watts, and negligible when it's not firing (ie when the bike is stationary). Magnet is firing only around 8% of the time.

Assembled Option:

For those who would prefer to purchase a pre-assembled Megabobra device, I'll be offering a small batch of ready to install systems as outlined int the post bel
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
@megabobra
Hi. I’m from Germany. Have Focus2 6.8 rim magnet. Can I also have your unlocker set? Grettings. @megabobra
 

littleleye

New Member
Jun 25, 2023
11
4
the Netherlands
Thanks again for the reply!

Unfortunately, I cannot disable location independent of apps on Apple.
When out of setup mode I tried turning my wheel which does provide a speed constantly (whether it is accurate is hard to determine).
Of course when riding my bike I powered down my entire phone to avoid any connection with GPS. The speed was measured with my exercise watch with GPS.
Still I get the speed sensor error, despite it was in the exact location it was running for 5min in setup mode. I don’t suspect it is due to cycling with the bike, but due to slight movement of the coil and cables while assembling the motor into the frame again. Hence looking for an option with less sensitive coil placement. Going to give the factory elektromagnet a try.
Will update in a few weeks, once I have received everything.
Update:
I have changed the electromagnet and positioned it back on the motor. Positioning is a lot easier with a smaller diameter coil. Again, I was able to determine the detection range of the hall sensor, positioned the electromagnet nicely in the middle. I got a perfectly stable speed for a kilometers while in setup mode. Thereafter, I went out of set-up mode, spin my wheel and also got a good speed read.
Mounted the motor back on my bike, cycled a few hundred meters with my phone off before I got the sensor error again :(. I have tried cycling at a low speed (<25k/h - so below the legal limit) and at a faster speed (>28km/h - above the legal limit). Both result in the error within a few hundred meters. I have no clue anymore why the system is not working as intended.

Looking at the Eplus derestrict device, they also mention that their device is not compatible with the regular Bosch Performance line (Only for the CX, CX race and Cargo line) Eplus Website. So, it seems there is a difference in the regular Performance line making it more difficult to derestrict.

I give up at this point. If there is someone that wants to buy the Megabobra from me let me know, I only changed the elektromagnet. Everything else is "original". Be aware that the height of the elektromagnet is 20 mm, make sure you have sufficient clearance on your bike. See pictures. I secured the magnet with hot glue, which worked perfectly.

IMG_0839.jpeg IMG_0837.jpeg IMG_0836.jpeg
 

megabobra

Active member
Jul 24, 2022
264
267
Australia
Update:
I have changed the electromagnet and positioned it back on the motor. Positioning is a lot easier with a smaller diameter coil. Again, I was able to determine the detection range of the hall sensor, positioned the electromagnet nicely in the middle. I got a perfectly stable speed for a kilometers while in setup mode. Thereafter, I went out of set-up mode, spin my wheel and also got a good speed read.
Mounted the motor back on my bike, cycled a few hundred meters with my phone off before I got the sensor error again :(. I have tried cycling at a low speed (<25k/h - so below the legal limit) and at a faster speed (>28km/h - above the legal limit). Both result in the error within a few hundred meters. I have no clue anymore why the system is not working as intended.

Looking at the Eplus derestrict device, they also mention that their device is not compatible with the regular Bosch Performance line (Only for the CX, CX race and Cargo line) Eplus Website. So, it seems there is a difference in the regular Performance line making it more difficult to derestrict.

I give up at this point. If there is someone that wants to buy the Megabobra from me let me know, I only changed the elektromagnet. Everything else is "original". Be aware that the height of the elektromagnet is 20 mm, make sure you have sufficient clearance on your bike. See pictures. I secured the magnet with hot glue, which worked perfectly.

View attachment 124042 View attachment 124043 View attachment 124044

Very sorry to hear this, and apologies for my oversight on the motor type - I'll update the first post to mention this is specifically for the CX range. Reach out to me directly if you prefer, I'm happy to refund your payment.
 

megabobra

Active member
Jul 24, 2022
264
267
Australia
Hi. I’m from Germany. Have Focus2 6.8 rim magnet. Can I also have your unlocker set? Grettings. @megabobra
Hi Wart,
I haven't got plans for another batch at the moment as there simply are not enough numbers. That and of course given Littleleye's experience above, I'm reluctant to accept any further payments until there's some confirmation of successful use of the devices. I'll note your name down regardless and will reach out if anything changes.

In the meantime, you can have a go a building the device according to the tutorial in the first post. Please reach out if you have any questions.
 

Canyon

Not the real Canyon
Jul 28, 2023
7
4
Belgium
Update:
I have changed the electromagnet and positioned it back on the motor. Positioning is a lot easier with a smaller diameter coil. Again, I was able to determine the detection range of the hall sensor, positioned the electromagnet nicely in the middle. I got a perfectly stable speed for a kilometers while in setup mode. Thereafter, I went out of set-up mode, spin my wheel and also got a good speed read.
Mounted the motor back on my bike, cycled a few hundred meters with my phone off before I got the sensor error again :(. I have tried cycling at a low speed (<25k/h - so below the legal limit) and at a faster speed (>28km/h - above the legal limit). Both result in the error within a few hundred meters. I have no clue anymore why the system is not working as intended.

Looking at the Eplus derestrict device, they also mention that their device is not compatible with the regular Bosch Performance line (Only for the CX, CX race and Cargo line) Eplus Website. So, it seems there is a difference in the regular Performance line making it more difficult to derestrict.

I give up at this point. If there is someone that wants to buy the Megabobra from me let me know, I only changed the elektromagnet. Everything else is "original". Be aware that the height of the elektromagnet is 20 mm, make sure you have sufficient clearance on your bike. See pictures. I secured the magnet with hot glue, which worked perfectly.

View attachment 124042 View attachment 124043 View attachment 124044
Damn, then I got the same problem....I have also just a regular performance line. I wanted to install the device this week but it seems that I am going to sell my device to 😕
 

ready13

New Member
Sep 7, 2023
4
4
USA
Damn, then I got the same problem....I have also just a regular performance line. I wanted to install the device this week but it seems that I am going to sell my device to 😕
Dang Canyon, I'm really sorry to hear this. If you decide to sell, I'd be interested to purchase yours. I have been meaning to build one but havent found the time. I have a good friend who is a bosch tech (and pro-tuning) looking for work arounds. He is working on telling me why performance line may have this issue while CX may not. So far, he is under the impression that likely CX motors will see the same issues down the line, we will see.
 

littleleye

New Member
Jun 25, 2023
11
4
the Netherlands
Dang Canyon, I'm really sorry to hear this. If you decide to sell, I'd be interested to purchase yours. I have been meaning to build one but havent found the time. I have a good friend who is a bosch tech (and pro-tuning) looking for work arounds. He is working on telling me why performance line may have this issue while CX may not. So far, he is under the impression that likely CX motors will see the same issues down the line, we will see.
@ready13 , my device is also available for purchase as mentioned above if you are interested.
 

megabobra

Active member
Jul 24, 2022
264
267
Australia
Damn, then I got the same problem....I have also just a regular performance line. I wanted to install the device this week but it seems that I am going to sell my device to 😕

That's a real shame. There's quite a few in the thread who have been looking for a device so they might snap it up.

@scm007, @John-E, @yomoe, @Spagnol
If you haven't been following, the devices aren't working with the standard performance line models, only the CX. So if you're still looking for one of my prebuilt devices and have a CX version motor, reach out to Canyon.
 

littleleye

New Member
Jun 25, 2023
11
4
the Netherlands
Im from the netherlands, you think i can use it on my bike? The magnet is on the breakdisk CUBE STEREO HYBRID 140 HPC TM 750 FLAS/OLI 2023 S - CUBE Stores Nederland
@Patcho, yes it should work. You have a regular speed sensor (no rim sensor).

See first post from megabobra:
For those who have been following the existing Derestricting bosch smart system thread, this will be old news, but I figured it be a good idea to branch the build of the Megabobra device into its own thread to manage questions without cluttering the existing topic.


Quick Refresher:

The Megabobra device is an arduino-based open source derestricter for the bosch smart system with rim magnet . It's tested and working with the Performance Line CX range of motors only - please note it is not working with the standard Performance Line range (non-CX). It uses a small electromagnet to replace the rim magnet, allowing the existing speed limit to be lifted to a value of your choice. The build needs some soldering experience but nothing too complicated once your source the components.

I've put together a detailed build guide here.

Some FAQ:
  • YES it will disrupt your total trip distance and odometer, but it's a simple multiplication to get the true figures. ie reported trip distance * chosen multiplier = true trip distance.
  • YES it should work on setups without the rim sensor. Instead of positioning the elctromagnet against the motor case, position it against the speed sensor.
  • Total power usage when the magnet is firing is ~2.4watts, and negligible when it's not firing (ie when the bike is stationary). Magnet is firing only around 8% of the time.

Assembled Option:

For those who would prefer to purchase a pre-assembled Megabobra device, I'll be offering a small batch of ready to install systems as outlined int the post below.

According to megabobra, you should position the elektromagnet against the speed sensor. So you have to:
- Move the current speedsensor somewhere close to the motor or lengthen the cable of the elektromagnet so you can please the speedsensor wherever you want.
- Place the sensor of the Megabobra on the place of the original speedsensor (so it can register the revolutions of your wheel).
- Place the elektromagnet against the original speed sensor.
 

ready13

New Member
Sep 7, 2023
4
4
USA
@ready13 , my device is also available for purchase as mentioned above if you are interested.
Littleleye, sorry I somehow missed yours was also for sale. If Patcho hasnt already purchased, Id definitely consider. What would be total cost with shipping to US? I tried to send you a PM but am unable (account too new perhaps?). Try to send me one if you are able and we can move from there.
 

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