Alternative wiring R80 G/S

Stevesplatto

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Hi all,
Need to rewire my G/S. Thought about getting a factory main loom and making the sub looms myself.. Looking at my loom there seems to be a lot of unnecessary wiring. That loom to the front light is a weak spot too (repaired it twice already).
Thinking if I swapped out all the BM switchgear for something more substantial I could loose the relays. I'd need to up the wire sizes off course but no bad thing I think.
Anyone got any leads for a simplified airhead wiring diagram?
Has anyone built a custom loom for these?

Cheers
Steve
 
Try the Old School Airheads forum over on ADV Riders - I recall some topics on there from guys who have fitted some form of electronicly switching distribution board next to the battery.

In my experience the current BMW switchgear is unbranded rubbish and you will be lucky if it survives more than a few weeks, so alternative switchgear is the way to go- good cheap stuff is easy to find these days, unless of course you buy BMW genuine parts.
 
I rewired my friend's R65 café racer earlier this year. Started with a copy of the original wiring diagram from a Haynes manual and just deleted all the excess wiring with tip-ex including diode board and sparks. Made a new copy of the diagram then added the recommended Boyer and Electrex World Regulator/Rectifier connections. Easy! Only one small fire. The only mistake was that the sub-frame didn't earth properly to the after powder coating so we had to clean the contacts and add an extra earth cable for security.

Retain the original wire colours wherever possible and all wiring stuff available from Vehicle Wiring Products. Buy the proper ratchet crimp tool and avoid solder where possible.

It does take a while to do and costs more than you'd think in consumables if done right. Because we were changing lights, ignition, switches, charging it made sense but if it was a standard bike, I'd fork out for a standard loom myself. The price of a new loom for my '93 GS is crazy money but more reasonable for the earlier bikes.
 
Thanks for the replies.
My goal is to simplify the wiring as much as possible:
On/Off ignition switch and start by side panel (less wiring to H/L)
Toggle switch for the lights.
Lose all extraneous wiring.
Probably keep the handlebar switches (not great but the alternatives in the vehicle wiring shops I've seen so far are worse..)
Got all the crimping kit (I'm a sparks). Thinking of using uninsulated crimps with a touch of solder for luck.
cheers
s
 
i have done a bit of wiring on airheads, although my aims were slightly different. as well as simplify the wiring, i wanted all the components bmw stuffs in the headlight moved elsewhere. also, i wanted as much of the wiring fused as possible. bmw leave a huge amount unfused as standard. unfortunately, although i have simplified some bits, i have ended up with more relays :blast

i think the switches are fine, and in the models i've worked on, the main/dip is not even relayed as standard.

if you crimp wires properly, and most amateurs and bike pros don't, you don't need to solder them as well. if you're not experienced at soldering, you may well make the joint worse.

for real simplicity and to enable the use clean, simple switchgear, something like this is probably the answer, though i've not used one.

http://motogadget.com/en/electrics/...m-unit-digit-tastersteuerung-u-sicherung.html
 
I've made a few custom looms over the years. To do it properly isn't cheap and to be honest it's cheaper to buy a genuine one.
 
The Motogadget v2 and M Button switch is the setup I was thinking of - if you buy them both there is little else you need apart from the final wire from the v2 to the item, and it can send two signals down the one wire so even they are reduced.

And it will be cheaper than a harness, relays, fuses and and switches at BMW prices.
 
Thanks for the replies.
My goal is to simplify the wiring as much as possible:
On/Off ignition switch and start by side panel (less wiring to H/L)
Toggle switch for the lights.
Lose all extraneous wiring.
Probably keep the handlebar switches (not great but the alternatives in the vehicle wiring shops I've seen so far are worse..)
Got all the crimping kit (I'm a sparks). Thinking of using uninsulated crimps with a touch of solder for luck.
cheers
s

Hey Steve.
I have replaced a lot of the wiring on my 1991 R80GS. I'm a sparky too so wasn't that fussed with it. The way they wired from the factory is in my opinion ridiculous. It had about 30 bloody earth wires. I lost a few of my relays & kept what I thought to be useful - not much!
I don't have a key (not worried about it getting stolen) just a toggle on off switch on the side of a custom battery box that sits up under the seat. I lost the big battery & put in a small motobatt one.
I used a cheap generic off/run switch on the bars. I got rid of all the BMW controls & put on a tomaselli dual cable throttle, KLR brake setup & clutch lever I had lying around with it's great easy generic switches.
I shifted my main earth off the gearbox & onto the frame I think where the battery box used to be. I also got rid of the speedo etc & wired in a cheap danmoto speedo but used the park lamp in the generic cheap round headlite in parallel with the gen lite on the LED display as the exciter for the alternator.
I used whatever wiring i had at the time so nothings really colour coded however there are so few wires running now I can pretty much pick what they are.
Needless to say I'm more of a KLR owner than a BMW owner but I can live with that.

Hope this helps
 
Thanks for the replies everyone.
I also want to lose as many wires going to the headlight as possible to eliminate the weak spot where the loom enters the cowling.
Motogadget device looks excellent but mucho bucks :-/.
Looking for quality generic switching but most I've found don't look all that convincing.
Found an excellent supplier for loom accessories:
http://kojaycat.co.uk
cheers
Steve
 
I'm using the M unit and M lock on the Caff Racer, some very interesting pieces of kit!

All relays and fuses disappeared, not cheap but well worth while particularly as it is ALL LED.
 
Hi.
Trying to semplify an existing 1981 G/S wiring.
I really do not understand why BMW built such a complicated charging wiring with separated rectifier and regulator.
I'm thinking to replace the charging circuit with a simple integrated regulator from any other motorcycle out there (may be an Harley-Davidson oem part).
 
Does anybody ever tryed this way? Connecting only the 3 main wires from alternator directly to the rectifier/regulator inputs :unsure:
 
Hi.
Trying to semplify an existing 1981 G/S wiring.
I really do not understand why BMW built such a complicated charging wiring with separated rectifier and regulator.
I'm thinking to replace the charging circuit with a simple integrated regulator from any other motorcycle out there (may be an Harley-Davidson oem part).
IMHO,there is no simpler wiring harness ever fitted to a motorcycle than the set up on a g/s,
Assuming of course you intend to retain oem switch gear etc.
The charging system is on a separate subloom any way.
If you chose to use a 5 wire reg/rec just connect the 3 phases direct to the unit.
Again,can’t really see a single advantage to this set up on a standard bike
 
Hi.
Trying to semplify an existing 1981 G/S wiring.
I really do not understand why BMW built such a complicated charging wiring with separated rectifier and regulator.
I'm thinking to replace the charging circuit with a simple integrated regulator from any other motorcycle out there (may be an Harley-Davidson oem part).
Because it was designed 50 years ago Maybe even more and it works! And contrary to the allegedly superior Jap bikes who burn out regulators "frequently"

You know when it is charging when the light illuminates with ignition on and goes off over about a 1000rpm and if it does not go out or does not come on with ignition then you KNOW it has a problem Plus it feeds back to the Battery by a main cable thereby reducing main loom loading!
 
As an addition to the above,
Nearly every single bike that utilises the 5 wire reg / rec suffers from burnt /overheated wiring
Or if the perpetrator is quite often stupid enough to try and hide the Reg Rect unit because of Aesthetics!!

This modern world annoys me with the Form over function mentality!
 


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