CANbus electrical system

[Marvin2Shoes]

After viewing many YouTube videos on the subject and hearing anecdotal accounts of motorcycle experts I have heard a unanimous message that "CANbus electrical systems reduce the amount of wiring in a vehicle while allowing multiple components to receive information from a single sensor"
The second part of this is true... A sensor can send information to multiple other components but only very few sensors take advantage of this e.g. rear wheel speed sensor used for speedo and ABS. Reduce the wiring? Hah! Have any of you pulled the R1200 harness out and looked at it close up? The four large connectors used for the ECU and the ZFE unit would be more at home in a supercomputer than a motorcycle!
The amount of wire I pulled from the R1200 harness was mind boggling... so much for 'saving on wiring'.
The CANbus is all about moving servicing into dealerships and NOTHING about helping the motorcycle enthusiast to maintain their pride and joy.
The majority of faults shown by canbus are difficult to clarify and some are downright baffling. The regularity with which poor grounding and electrical noise disrupt the system renders it permanently in the category of "not if you want reliable electrics".
This is a problem for the longevity of this mechanical wonder.
I can see the only way that the R1150 models and later are going to become classic motorcycles is if they have a reliable electrical system transplanted. To this end I have been working on a replacement wiring harness. Its design is almost complete and for those of you still reading, can be viewed here (post# 63617):

https://speeduino.com/forum/viewtopic.php?t=5967

Please let me know how the readability of this diagram compares with the one in the Haynes manual.
All wiring will be completed in Tefzel wire with Deutsch connectors and wrapped in double wall, adhesive-lined heatshrink and 3M vulcanising rubber tape. All major electrical components and sensors have been swapped for easily sourced, quality aftermarket options with only the Throttle Position Sensor, Crank Sensor and Camshaft Sensor being original BMW parts at this point. The dual spark system with original (updated} coils is being kept. An aftermarket gear selection display is being sorted. A GPS speedo is being implemented to show ACTUAL speed. FM radio and blown bulb warnings will NOT be implemented. LED bulbs will be used all round (without special canbus friendly nonsense bulbs or annoying warnings).
Electrically actuated air intake will be software controlled (two stepper motors on throttle body will be relegated to the dustbin.
Original injectors are high impedance and are therefore compatible with aftermarket ECU's without extra work needed.

The airbox is MASSIVE and has been removed. That is where part of the 25 litre fuel tank should have resided to get the centre of gravity lower. The lithium battery (about 1kg) will be located under a hatch where the fuel cap used to be along with the much smaller ECU, coil driver, breakers and air-filter for fan cooled ECU/Coil driver.

All circuit protection will be replaced by manually resettable circuit breakers to alleviate side-of-the-road breakdowns which are repairable but not able to be completed due to a lack of available spare fuses. It also fixes problems caused by black box technology where if one function ceases to operate the whole black-box worth hundreds of dollars doesn't need to be replaced.

If by now you have smoke coming out your ears at the suggestion that BMW purposefully built obsolescence into their electrical systems then I'll give you a few more years for the realisation to sink in. It will become apparent to you when your ABS throws 'pressure sensor errors' causing your brake light to stay on and your cruise control to become non-operational until you pull up at the side of the road, power down & restart to get it working again and be told you're up for a third of the value of the bike to fix it. Sounds more like a Microsoft operating system sold by a scammer than a motorcycle, huh?

If anyone is interested please say hi and have a chat as this project has been a real learning curve and has had many pitfalls along the way. It is becoming quite outside my comfort zone with the move into ECU parameter programming for which there have been, to my knowledge, no R1200 bikes subject to the modification to-date and only one K bike. Please let me know if you have seen a R1200 that has been modified electronically as a community will keep these quirky bikes on the road long-term and the more information given & received will speed up that outcome.

[Doctor T]

This and your link are very interesting. Seem like a long job and would love to see the picture as you go. Good luck

[Marvin2Shoes]

The engine is now suspended in a frame on wheels for ease of handling.
It still needs a flexible exhaust gas removal option and a better mount for the fuel tank.

20230912_092927[1].jpg (478.25 KiB) Viewed 2022 times

[Marvin2Shoes]

The engine is running on Speeduino ECU and it only took me 6 months lol

[Marvin2Shoes]

Here is the most up-to-date wiring diagram:
https://speeduino.com/forum/viewtopic.p ... 876#p65876

[burridge01]

I doff my cap to you Marvin,always good posts.How you haven't burnt the bike is testament to your determination

[TJRL]

I have always thought that CANbus was a great idea but not so good in practise.

If I remember correctly in its basic form CANbus is just four wires for the whole loom; positive, negative and 2x low voltage data wires. But no one seems to have actually built a vehicle like that.

Also, IIRC, back in the day Hornby trains tried to go CANbus replacing the variable 12v in the track (to control the train's speed) with a data signal "added" over a constant 20v. The ideas was that trains could be on the same track going at different speeds or even in different directions and things like lighting in the carriages would stay on even if the trains was stationary. Great in principle but took them ages to get the bugs out.

[Marvin2Shoes]

I doff my cap to you Marvin,always good posts.How you haven't burnt the bike is testament to your determination

The determination required to deny myself the ecstatic relief of a beemer conflagration is gradually waning.

[Marvin2Shoes]

I have always thought that CANbus was a great idea but not so good in practise.
If I remember correctly in its basic form CANbus is just four wires for the whole loom.

Add data into an unshielded system that can be affected by any RFI event in a world chock full of RFI... what could possibly go wrong?
If you want the battery to send "hello world" to a light bulb it would be simple wiring. Then we add ECU, power distribution systems and assorted third party afterthoughts and the whole thing becomes a study in unnecessary complication.
Sometimes simple is just simpler.
CANbus is about to morph into an encrypted data system that won't be accessible to the end user. Companies like BMW, Apple and John Deer are absolutely going to use these technologies to lock us all out of our own servicing.
I welcome anyone to argue against this but please make sure you spell my name right when, after it all happens, you quote my words

[Doctor T]

Fuses and direct wiring was so simple