Hi everyone,
My 86 K75 seems to be running a little rich.
There is a constant sooty deposit on the silencer.
is there a way to adjust the calibration of the air sensor ??
I've never heard of an instrument staying in perfect calibration for over 20 years.

Malcolm
Joburg
South Africa

Yes there is a a setting in the air flow meter.
Before touching it, I would first check the air filter and the fuel pressure.
A plugged air filter or a bad fuel pressure regulator (too much pressure) can create this problem too.
The bypass screw can be accessed without opening the air box. On the top of the housing for the air box/air filter you will find a small plastic cap. This is where you put the allen key to setup up the air bypass.

Hi Bert, Thanks for the info. The air filter is almost new, I'll check the fuel pressure. I suppose the other thing to check would be the air and coolant temperature sensors for any tweeking.
Despite the sooty deposit the bikes fuel consumption is OK.
I do a daily 75km round trip on the freeway, Joburg is about 1800m above sea level and the bike does almost 22km/l if I keep to about 100kph and drops to 19km/l if I travel at 120/130kph.

First I looked at your gas consumption and was amazed.
I had to look at your first post and saw that this is for the K75 and not the K1100. Your gas consumption is identical to mine on my 86 K75. I call my K100 the glutton or the pig. I cannot get under 16km/l and this when riding at 90-100 kph.
Considering the altitude that you ride, I would agree that an adjustment could be done.
Unless you have the equipment to analyse your exhaust, you should gradually modify the setup by opening the bypass by 1/4 turn and riding for a week. Check the spark plugs after the week and see if it's enough.

Bert

Hi Bert, There is very little difference between the fuel consumption of my K11 and K75. The K11 is actually slighty better on a long run at 120-140kph. The K11 will start to guzzle the gas when running at 160-180, dropping to around 16-17l/km.
The K11 dosent have the slightest trace of soot on the exaust.

Malcolm

With regards to the altitude, some of the bikes came with an 'altitude plug' to correct the settings. Maybe you should be looking a bit more in that direction?

My don't have the altitude plug, already looked at that.

So maybe you should try to fit one.

I've always assumed that as it isnt fitted then my EFI brain dosent support it. But we all know about assumption.
Its something else to look into.

Just have a look at REALCom or one of the other sites if the number for the ECU is different. As far as I know the brain is the same ;-)

Hi, I live at sea level, but wen riding thru andes we climb up to 4000mts, wen reaching 2000mts I insert the plug and runs fine. The plug is only a jumper and the conector is by the coils, a wire with a black cap.
Best regards
JAP

Thanks for the info. I will look for this connector.
Here is a suggestion for you.
If from time to time you are using this altitude plug, why don't you put a rocker switch in stead of the plug?
It would be a quick way to switch On/Off without having to get off the bike.

The plug is a jumper between pin 9 and 11 of the FI computer.

Bert

Not to add any confusion to this discussion, but I thought I might add a few photos of the Altitude connector on the bike and a shot of the plug. I hope that it helps somebody.

BeachGuy
Riding a 1995 K75

http://beachguy.smugmug.com/Motorcycles/BMW-K75/9842031_26y45#681138041_tJvhs

http://beachguy.smugmug.com/Motorcycles/BMW-K75/9842031_26y45#681138048_uinVs

http://beachguy.smugmug.com/Motorcycles/BMW-K75/9842031_26y45#681162445_biBCq

http://beachguy.smugmug.com/Motorcycles/BMW-K75/9842031_26y45#681138171_dvUQ4

Muchas gracias.
Una imagen vale más que mil palabras
¿Qué piensa usted sobre la instalación de un interruptor?

Ok....., I just said " Thank you very much, a picture is worth 1000s words. What do you think about the idea of installing a switch ?"

Bert

A switch would be good if you road in an area where you changed altitude quite often. Above 1400 meters or about 4500 feet of altitude, you will need the plug.
I live in Costa Rica at about 3,000 feet and travel the whole country. Some day trips are as high as 4500 feet and never have a problem with out the plug inserted. How ever if I lived or stayed higher than I'm at, I would insert the plug.
I can tell on the GREAT COSTA RICA ROADS, trying to pass 3 or 4 trucks at altitude can be brutal. The exhaust pipe will turn a very pretty black. It will run rich and definite loss of power. But once back down to lower elevations it cleans right up.
In a everyday situation like this a dash mount switch would be handy.
If your above 1400 meters all the time you need the plug 24/7. Also helps with the starting at that altitude.

Hope this helps,
BeachGuy

Regarding the switch its a good idea for frecuent altitude changes, I think I´ve read about somone installing it wen searching for info and learning that is just a jumper.
Best regards
JAP
PS Manejen con cuidado

A picture SAVES a thousand words.
It would be handy for me when I go to the coast.
Malcolm