elecrical

[WILDPIG]

can bus electrical-- can some one clue me in on this system bmw uses? basic differences between can/bus vs fused?

[deilenberger]

can bus electrical-- can some one clue me in on this system bmw uses? basic differences between can/bus vs fused?

It's a bit of a complex subject. There were some good writeups on it at a few other websites - which if I find - I'll pass along.

Basics - the CANBUS system uses intelligent devices that talk to each other over a network (CANBUS network). The devices can transfer information and commands between each other. CANBUS actually refers to the network protocol used - but it's become used as a generic term for the new wiring designs.

With CANBUS there are several bigger modules (devices) such as the instrument pod, the engine controller, the brake/ABS controller and the body controller, plus some smaller ones like the alarm option. There are no fuses since all switched devices are controlled by the body controller (ZFE) - which will sense if there is an excessive current draw and shut that circuit off. It resets the circuit when the power is cycled off and on. Different devices talk to each other - simplifying control (the ABS controller talks to the speedo/instrument cluster to determine speed, and if you have DSC - control can be passed to the engine controller to control wheel-spin.. etc. etc..)

The big plus for the CANBUS system is simplicity of the wiring harness and the ability to do things that would have required bunches of wires - now being done with only a few wires.

The downside is - it's harder to add circuits to the system. The usual and IMHO best way to do so is with an auxiliary fuse box, which can be on switched power using a relay switched by the ZFE (body) module. The big upside is - hacking up the wiring harness to add/modify things should be a thing of the past, and if it is hacked up and something goes wrong - it's not likely to smoke the harness, as used to happen on fused bikes (especially BMWs that had quite a few high-current unfused circuits..)

IMHO - it's a GOOD THING. If I can find the articles (Motorcycle Consumer news had one, and I believe the BMW Owners News) - I'll pass them along.

[celticus]

Don, What do you mean by ZFE (body) module?
Mark

[deilenberger]

Don, What do you mean by ZFE (body) module?
Mark

The modules are referred to by BMW with 3-letter acronyms. Don't remember what ZFE stands for - but it's the central body control module - ie - replacing the old electrical box on older bikes (does switching and current limiting).

[deilenberger]

Found the article by an old friend - Anton Largiader..

http://www.bmwra.org/otl/canbus/

That should make it a tiny bit clearer..

[MJB]

Don

I am new to the R1200R.
Actually have only had the bike for about a week.............so far great.
I am planning on installing additional electrical accessories such as additional front light and rear lighting similar to your bike.
Also possible electrical for a heated vest, and I would not mind installing an outlet such as an accessory plug to charge a cell phone.

I believe there is an accessory that I can purchase which would be installed under the seat to which I then attach my accessories too.
Something like a "Fuse Box" with about 4-6 outlets.

I am not as handy as you are in tapping into the electrical system.
I would have the dealer install the "Fuse Box" and then I could possibly install the accessories as I purchase them


Any suggestions?


Michael

[deilenberger]

Michael - sounds like a good plan. CycleGadgets probably has everything you need: http://www.cyclegadgets.com/Products/?cat=ELECT - the PowerLet sockets work well, and the Centech fusebox is a favorite.

I think it should work out fine..

[WILDPIG]

WELL MY NEW 08 R12 OUGHTA BE HERE IN NC BY THE 25TH--- GOT THE TINTED SPORT WIND SHIELD,, FULL GIVI.... AN A FEW OTHER ODDS N ENDS...............AN EXTRA POWER PT................. NOW ALL I NEED TO DO IS GET RID OF THOSE MIRRORS-- BUT DAM RIZAMA'S ARE OUT RAGEOUS IN PRICE.............

[NeilS]

Many years ago I read a wonderful book with a title something like "How to Repair Your Foreign Car--A Manual for the Beginner, Your Wife, and the Mechanically Inept." One of the chapters told of the "national" characteristics of each country's vehicles. For the Germans, the attitude was, "How dare you, with your crude tools and your pittance of knowledge, meddle with this flawless product of The Master Race?"

While the theory of the CANbus is sound, and it recognizes the fact that, these days, silicon is cheaper than copper, I think the fundamental reason BMW uses it is that they believe their customers are too stupid to successfully modify their bikes' electrical systems. Since I am 1) an electrical engineer, and 2) not a member of The Master Race, I resent this attitude. Definitely NOT a good thing.

[deilenberger]

Since I am 1) an electrical engineer, and 2) not a member of The Master Race, I resent this attitude. Definitely NOT a good thing.

As an EE - isn't simplicity better for both efficiency and reliability? I have no problem adding my own fuse box and simply working off that. I much prefer that to trying to fix a harness that someone else has hacked up (especially with those GD "Scotchlok" taps..)

I picked up a spare harness for my R (it was one of those "too good a buy to pass up.. and I really didn't intend to buy it" things on Ebay..) and it's amazingly simple and light compared to a K75S harness (which I've had the pleasure of replacing after it went up in smoke due to modifications made by a mechanic..) To add on to the R - all you need is a Centech fuse box - and if you want switched and non-switched fuses - the split one and a single relay. It fits nicely under the seat, is easily accessable and has more holes for connecting things than even I can imagine connecting.

I like CanBus - but my background was basic physics not EE.. so we probably have a different perspective on it..

[famousperson]

WELL MY NEW 08 R12 OUGHTA BE HERE IN NC BY THE 25TH--- GOT THE TINTED SPORT WIND SHIELD,, FULL GIVI.... AN A FEW OTHER ODDS N ENDS...............AN EXTRA POWER PT................. NOW ALL I NEED TO DO IS GET RID OF THOSE MIRRORS-- BUT DAM RIZAMA'S ARE OUT RAGEOUS IN PRICE.............

What's an "extra power PT?"

[NeilS]

Well, I guess it depends on how you define efficiency and reliability. Weight? Definitely. Cost? I'm not so sure. What's the cost of the software development divided among a relatively small number of motorcycles? Reliability? Those weatherproof automotive connectors are pretty reliable these days (clearly not the case for the Scotchloks), but what about software reliability?

I'm not complaining about the CANbus, just this particular application for it. I think it's perfectly fine for a "closed" system. But now we're back to attitude. I've never thought of my cars and bikes as closed systems, and the manufacturers, increasingly, do.

[MJB]

Michael - sounds like a good plan. CycleGadgets probably has everything you need: http://www.cyclegadgets.com/Products/?cat=ELECT - the PowerLet sockets work well, and the Centech fusebox is a favorite.

I think it should work out fine..

Don

Thanks for the info....I will look into the Centech Fuse Box.
Looks simple and clean...

Michael