JohnGS1100 Tuning Chip

[King Rat]

I feel really tupid because I have read so much of this thread and understand very little of it - modern bikes with electronics and fuel injection are totally confusing. Old fashioned bikes with pints and carburettors I understand and can deal with.

Is there anyone who knows about the fuel injection who could help me to fit one of these chips to my 2003 Adv please? Would Steptoe do it if I took it with me at service time? I know I won't do it right if I try and do it myself.

I want better fuel consumption and better (I might already have) good midrange. I don't think the bike has ever revved over 5000 in its life, it doesn't need to as far as I am concerned. I am happy at a nice steady average, making my fuel and tyres and brakes go as far as possible. If the chip will help get even more miles to the gallon, then I would be very happy

 

[JohnGS1100]

Yes the chip gives more better consumption
Has faster timing advance and exploits the burning of gasoline 95+ octane.
The stock chip is for very low octane petrols, has slow timing advance and very lean fuel.

 

[King Rat]

Yes the chip gives more better consumption
Has faster timing advance and exploits the burning of gasoline 95+ octane.
The stock chip is for very low octane petrols, has slow timing advance and very lean fuel.

Right, I need to talk you about 2 chips then please.....bike 1 is just coming up to 100,000 and the other is on 78,000. Both are 1150GS. Is there any difference between single spark 1150 and 2-spark 1150? As far as the chip goes I mean!

 

[JohnGS1100]

Yes the chip for single spark is difference that twin spark. The miles does no matter.

 

[Roger 04 RT]

Yes the chip gives more better consumption
Has faster timing advance and exploits the burning of gasoline 95+ octane.
The stock chip is for very low octane petrols, has slow timing advance and very lean fuel.

The optimum Ignition advance (spark timing) of a gasoline engine, doesn't change with Octane, as long as the octane is the minimum required for the engine.

There is already a Coding Plug configuration for sub-standard (too low octane fuel); but once you have the correct Coding Plug for the ignition of fuel that is not-sub-standard, additional Octane doesn't matter.

Spark timing for not-sub-standard fuel (in other words, sufficient octane) is set by the engine maker so that the maximum pressure created by combustion is the best number of degrees after TDC (around 17 degrees). This is a function of engine RPM and engine mechanical layout.

Therefore once the minimum octane to suppress pre-ignition is achieved, more octane and altered spark timing is of no benefit.

About halfway down this page are good comments on spark advance: http://www.megamanual.com/begintuning.htm.

Here is another good article: Spark Timing Myths Debunked.

 

[spoons]

Thanks, SOB, I didn't know about that fantastic resource. Couldn't find my answer though, unfortunately. Still got a disconnected copot stranded on the back of my bike.

 

[NitroMax]

Well, went to my friends garage on Friday to check CO, but decided to start from scratch so I did the BBS's/throttlecables/TPS/synch/CO-pot all over again.

TPS is exactly on 0.366, CO-pot is inbetween the 1 & 2 pins on 205 and the 2 & 3 pins on 792 ( so the 205 just a bit lower and the 792 just a bit higher, since one can only adjust with the 1 screw ).

We couldn't get CO below 3,1 % without screwing the other values up badly so I left it that way.

It idles very nicely at about 1050/1100 revs and runs very well in higher revs/gears, turning the throttle in 4th gear at 3000 revs it leaps forward ( for a 1100 cc boxer that is, I also own a 1300 cc 207 RHP VMax on NOS and a 1976 1200 cc dragrace Kawa Z1000 so I'm used to moving forward fast ). No KFR/surging and no hesitation on rolling away at the trafficlights.



Now for fuelconsumption

 

[King Rat]

I think over 1000rpm sounds too high for idle. Why does it run that fast at idle? Mine happily tick over at between 650 and 800. Both of them, one is twin spark (which might make it easier to obtain lower revs?) the other is a single spark 1150. I am not "getting at you" I am not well versed enough in these tuning tricks, and have no idea of EFI, but I would want a much lower tick over and just smooth running pulling away. Are you setting the bike up for faster running or something? How does your set up affect fuel consumption, which is again, something I am aiming to maximise.

 

[MattW]

I stand to be corrected but I believe factory spec for idle is 1050 rpm.

 

[JohnGS1100]

I think over 1000rpm sounds too high for idle. Why does it run that fast at idle? Mine happily tick over at between 650 and 800. Both of them, one is twin spark (which might make it easier to obtain lower revs?) the other is a single spark 1150. I am not "getting at you" I am not well versed enough in these tuning tricks, and have no idea of EFI, but I would want a much lower tick over and just smooth running pulling away. Are you setting the bike up for faster running or something? How does your set up affect fuel consumption, which is again, something I am aiming to maximise.

I stand to be corrected but I believe factory spec for idle is 1050 rpm.

Yes and yes..

The idle speed sounds too high because the boxer engine is airhead..
The factory settings is to 1050 rpm. I 'd like to 1000+ rpm, but..

The problem is in to the oil pump of boxer. The oil pump needs up to 1100 rpms for the correct pressure..
So if the bike stands much time on idle speed, the idle speed should be adjust to 1100 rpms. If the bike stands only for little time on idle speed, the correct settings is 1050 rpm as BMW said.. or lower as biker wants!!

 

[NitroMax]

No idea about fuelconsumption yet, have to check from now on.

I set idle to 1050/1100 because it says so in the manual, could set it lower if I wanted it too I guess.

[edit]
Oh, missed the 2 answers above
[edit]

 

[Comfy Old Boots]

Thanks, SOB, I didn't know about that fantastic resource. Couldn't find my answer though, unfortunately. Still got a disconnected copot stranded on the back of my bike.

Hiya, to the best of my knowledge (I have very little!), you can't have a lambda and a co2 pot on the bike at the same time. It's an either or situation. Heavens knows why you have both but if you have a lambda sensor you shouldn't need the co2 pot connected. Perhaps someone more knowledgable will be able to confirm that for you.

 

[spoons]

My research says you're right that they can't both be in use at the same time. I tested my lambda, which will easily rise when heated to a max voltage of 0.85v, and have that installed now but fuel consumption is still not good so I would like to try my COpot instead. Just looking for info on how to link the COpot from the back of my bike to the motronic, which is the missing cable.

 

[Comfy Old Boots]

What consumption are you getting? What type of riding? My 1150 gets 45 mpg city riding. My 850r gets 32 at best city riding. My 850 goes like stink though. Top end speed not as good as the 1150 but at lower speeds it's faster. My co2 pot could not handle altitude. Conked out on an overtake in the pyraneese near andora. As I understand it, the lambda works better.

If you like, id be happy to take a snap of the cable my co2 pot is attached to? Might help you track one down?

Here's what I got on a quick search. Your not alone!
http://www.ukgser.com/forums/showthread.php/196464-co2-potentiometer-r1100gs

http://www.advrider.com/forums/showthread.php?t=866011&page=2

 

[JohnGS1100]

Yes the lambda works better at altitude. By Co-pot is better to make little richer the AFR at altitude..
I can help. After adjust the CO-POT you sould tell to me what you want to change at fuel injection table at all revs of rpms.

 

[King Rat]

OOOh those replies are interesting. Thankfully I don't let the bike idle, I swirtch off for things like train crossings waiting for the barriers, rather than run at idle going nowhere. I don't let it sit on the stand idling while I get ready either - if the engine is running I like the wheels to be going round! That stance must have saved me from low oil pressure that I didn't know about!

I need to find my manual, rather than going by eye, ear and fading memory!

 

[NitroMax]

http://avoeten.home.xs4all.nl/Greeves/BMW R1100 GS .pdf

and

http://advwisdom.hogranch.com/Wisdom/OilheadMaintenance.pdf

and

http://www.ketchum.org/BMWmc/R1100.pdf

Electrics:

http://www.bmwgsclub.nl/schematics/R1100GS Schematics.pdf

That'll keep you busy for a while

 

[Steptoe]

Yes and yes..

The idle speed sounds too high because the boxer engine is airhead..
The factory settings is to 1050 rpm. I 'd like to 1000+ rpm, but..

The problem is in to the oil pump of boxer. The oil pump needs up to 1100 rpms for the correct pressure..
So if the bike stands much time on idle speed, the idle speed should be adjust to 1100 rpms. If the bike stands only for little time on idle speed, the correct settings is 1050 rpm as BMW said.. or lower as biker wants!!

My set my single spark 1150GS to idle at 650 RPM.
I set it to idle at that speed back in 2003, and it's covered 75K miles without any problems, and still idles at 650 RPM.

I like a slow idling bike, plus it will show up any potential ignition or fueling problems straight away.

 

[King Rat]

My set my single spark 1150GS to idle at 650 RPM.
I set it to idle at that speed back in 2003, and it's covered 75K miles without any problems, and still idles at 650 RPM.

I like a slow idling bike, plus it will show up any potential ignition or fueling problems straight away.

You set up my Adv too - it still idles at under 800rpm, unless the heated grips swell the throttle, then it holds the throttle wide open! Not good approaching junctions. I will be down in a week or so with her. Just waiting for that Triton to get finished.

 

[Roger 04 RT]

I like a slow idling bike too but find my dual spark isn't that happy below 1100. Have you had good results lowering dual-spark RTs?

One thing that happens with higher or lower than 1100 RPM on an Oilhead with an O2 sensor is that it develops trims. For instance, I've seen logs from guys with high idle, 1200-1300 rpm. During cold starting the bike runs lean at small throttle angles, which keeps them from idling well. Oddly a low hot idle would probably do the opposite and it might just improve cold idle, not sure.