Remap by Hilltop Motorcycles

[Magwych]

I agree with this statement.
I consider the lambda sensor is there to inform the ecu when the air fuel ratio varies from 14.7 to 1 ( in fact pulsed either side of this to enable the catalytic converter to work).
The ecu then alters the injector pulse width to maintain this 14.7 t0 1 AFR.
If the base map is altered the lambda sensor will detect the AFR is wrong and report it back to the ecu.....
I have installed a wide band lambda sensor ( for data logging) in the exhaust just behind the stock narrow band sensor and find it quite surprising how it manages to control the AFR to 14.7 to 1 in closed loop.
Which takes me back to my initial question. How can the base map be altered to change the AFR with the lambda circuit working in closed loop.?

Almost there .. It is a simple sensor. It changes voltage output in response to changes in the AFR, that voltage is measured back to the ECU.

The ECU makes the decision whether the AFR is wrong or not.

If you install a device that alter the information sent be the sensor, then the ECU is making the deicsions based on altered information. It does not know that the information has been altered. So your lamdba sensor sends a volatge output that equates to an AFR of 13.7, your device "adjusts" tha voltage by a factor of 0.93; assuming the voltage/AFR curve is linear, the ECU recieves a signal voltage from what it thinks is the lambda sensor in the exhaust saying that the AFR is 13.7/0.93=14.7, it really came from your device.

Now, if the ECU has a target AFR of 14.7 for the the load it is managing according to all the other sensors, then it will probably do nothing to the fuel mixture. It thinks it is running as lean as the man from BMW wants, but you have got an engine that is running as rich as you want....

It is only a matter of semantics, I suspect we are saying the same thing, i.e. that the lambda signal does influence the ECU, just the pedants like me pick up on the suggestion that the lambda is somehow "in control". It is just piece of very expensive metal whose electrical properties change when subjected to specific heat and gas concentrations. What to do with that information is decided by the ECU ...

Sorry, I promised myself I would not enter this one, work is that boring today

 

[Grim Reaper]

I think what Mistacat is trying to work out is how, if the ECU in closed loop mode alters the map to give 14:1 AFR, does altering the base map cause it to run richer? Because no matter what the map says it should adjust to give 14:1.
It is possible that the ecu has an AFR target table to work to (but I suspect that would only work if the Lambda sensor was wideband) or an adjustable offset to the lambda input. Or maybe the ECU is only allowed to adjust the basemap by a certain amount (say 3%) and if the base map is made rich enough the max adjustment allowed does not let the ECU bring the adjusted fuelling down enough to reach 14:1 AFR.
There was a diagram somewhere that showed how the sensors and the ecu interacted (may be on advrider's thread about wideband lambda controllers)

 

[Grim Reaper]

I can't edit my original post so I'll just add..
It would seem that the closed loop fuelling only applies up to around 6000rpm, so above that the ECU takes its fuelling directly from the map with no adjustments, this is when changing the basemap figures will have the most effect (IF the originals were insufficient)
It does not answer the original question though, How does the ECU deal with an adjusted basemap when in closed loop mode and not re-adjust it to give 14:1 AFR everywhere? (I use 14:1 in preference to Lambda 1 as it is easier to understand fuel air ratios than Lambda figures, and I know it is technically 14.7:1 but thats by the by)

 

[spm0912]

Some of the post's on this thread are starting to make my head hurt

I can understand some of you cleverer chaps wanting to know the why's and the how's but for the vast majority of us just trust that it works, I have no idea what electrickery Geoff does to the ECU but whatever it is my bike (which TBH I wasn't unhappy with anyway) is soooo much nicer to ride. Is it faster? Probably not, but it now accelerates without any hesitation, particularly between 4-5k revs. Worth £350, for me yes, though I only paid £250 as I'd had my previous GS done

There can't be many GS's left to do now eyes: but if you are still on the fence don't be put off by some of the technical stuff on here, some people just 'need to know' how things work, and TBH the world would be a poorer place without them.

Looking for a nicer, smoother ride? Hilltop remap, buy with confidence

Want to go faster? Look elsewhere!

 

[Mistacat]

I think what Mistacat is trying to work out is how, if the ECU in closed loop mode alters the map to give 14:1 AFR, does altering the base map cause it to run richer? Because no matter what the map says it should adjust to give 14:1.
It is possible that the ecu has an AFR target table to work to (but I suspect that would only work if the Lambda sensor was wideband) or an adjustable offset to the lambda input. Or maybe the ECU is only allowed to adjust the basemap by a certain amount (say 3%) and if the base map is made rich enough the max adjustment allowed does not let the ECU bring the adjusted fuelling down enough to reach 14:1 AFR.
There was a diagram somewhere that showed how the sensors and the ecu interacted (may be on advrider's thread about wideband lambda controllers)

Not sure what the parameters are but a lot more than 3%.
I have increased injector pulse width to give an AFR 12 to 1 and the narrow band lambda has quickly rectified this back to 14.7 to 1 and the ecu has learnt this, as after a few minutes I switched the device out of circuit and it showed 16 to 1 and then was corrected again by the lambda /ecu.

 

[Mistacat]

I just like to try and understand what I am playing with.
Not looking for HP just a smooth running bike.
At the moment using a BMW-AF EXIED lambda offset device which is working really well.
It is nice to be able to switch it to 14.7 afr and then try it at say 13.8 you can really feel the difference. ( as well as data log the Results)
At £300 not cheap but can be taken off and fitted to another BMW.
Have tried power commanders etc, but this unit is plug and play.

 

[Grim Reaper]

Having read through the ADVrider thread it would seem that +/-20% is the limit before it will switch the other way.
Just out of interest, do you have the BMW-AF EXIED fitted to a WC? I'd certainly consider fitting the TechEdge WB02 Wideband Lambda Controller to the GS (I have it on my Caterham allowing self mapping of the Emerald K6 ECU)
One thing that I did find astonishing from the other thread is that the dyno runs only used 9 of the 288 available cells on the fuelling map.

 

[Beemerman59]

Wouldn't this sort of stuff be better suited on Wilsdorf's tuning thread rather than this one, which is about the Hilltop remap?

 

[Mistacat]

Having read through the ADVrider thread it would seem that +/-20% is the limit before it will switch the other way.
Just out of interest, do you have the BMW-AF EXIED fitted to a WC? I'd certainly consider fitting the TechEdge WB02 Wideband Lambda Controller to the GS (I have it on my Caterham allowing self mapping of the Emerald K6 ECU)
One thing that I did find astonishing from the other thread is that the dyno runs only used 9 of the 288 available cells on the fuelling map.

I have the XIED fitted to a 2009 Mk2 GS.
I believe the TechEdge WB02 is similar to the Innovate LC1, I have been using LC1`s for many years but considered a permanent install of 2 units on a GS too bulky.
Reference the 9 cells populated in closed loop on the Dyno I did not know that and think that must be THE ANSWER. So Thank You.
I had overlooked the fact that on a Dyno , Due to load & throttle position you would only be in closed loop for a very short time.
I spend (according to the data I have recorded) about 80 % of the time in closed loop (progressive road riding), so a re-map would not suit me.
Having ridden this bike around cadwel park in those circumstances I would think it is in closed loop 20% of the time.
Dyno`s are essential for tuning race bikes.

 

[Mistacat]

Wouldn't this sort of stuff be better suited on Wilsdorf's tuning thread rather than this one, which is about the Hilltop remap?

Sorry, Beemerman, I did not intend to tie up this thread.

The questions asked were ,with this remap are the lambda sensors left functioning. Answer = Yes.
Question 2 , If so how is the closed loop overcome?
I expected with so many having had this remap done that they are the sort of questions they would have asked.( so would have been answered quickly)

I now have a theory I can except so will joyfully clear off back to the workshop. Thanking Grim Reaper for his input.

 

[duckspeed]

Calling Geoff from hilltop to explain in depth what is going on.
Mine has been done last week and feels like a different bike.

 

[Delboy777]

Calling Geoff from hilltop to explain in depth what is going on.
Mine has been done last week and feels like a different bike.

At the end of the day surely thats all that feckin matters is it not ? We know it works so ffs, end this thread !! its doin my head in. 72 feckin pages

 

[Sgt Bilco]

At the end of the day surely thats all that feckin matters is it not ? We know it works so ffs, end this thread !! its doin my head in. 72 feckin pages

Quite right mate and it's evolved into a load of old nonsense. As you rightly say, there is no doubt the bike feels a load better after the work has been done so who give s flying f*ck about "my cock is bigger than yours" power figures etc?

 

[Big Lee]

So, in your own words, you're 'no expert', but you are calling into question the results of expert tuning, calling it 'snake oil' and 'rolling road tweaking'??? Thin ice, fella, thin ice. Especially on a public forum.

Thats about the size of it and why am I on thin ice especially on a public forum? you gonna ban me or beat me up for airing my opinion, on a PUBLIC forum , just cos it doesn`t match yours?

One thing I find quite puzzling

BMW spend millions developing a LC GS1200 that produces an extra 15bhp.

They could have saved all that cash by just getting a remap

Exactly

 

[Beemerman59]

At the end of the day surely thats all that feckin matters is it not ? We know it works so ffs, end this thread !! its doin my head in. 72 feckin pages

Completely agree

 

[RedRick Esq.]

This is simple (to me any way)

Either get it done or dont ( I did and am pleased with the results) But FFS if you dont why spend so much time questioning, disbelieving or slagging off the results !

Its just bling that you cant see !

Oh hang on lets have a "Do Cymarc products or Touratech work" thread or lets slag Nippy norman off for selling Akrapovic stuff that may or may not enhance the bikes performance or looks

Get a grip

 

[The Grey One]

Seems to me that the argument that BMW spent a fortune developing a new engine when they could have got more power just by a remap misses the point.

I don't doubt they could get more out of the old engine themselves but the new engine is intended for future development. It takes the boxer into a new era. I am sure the good people at BMW didn't come up with a new engine on a whim. There will be sound engineering reasons behind the total re design and certainly more power to come.

One day I might be able to afford one!

John

 

[Bendy toy]

The LC engine should have lower metal surface temperatures and so lower Nox emissions. As that's the current bad boy in EU environmental politics they had no choice but to go for a new designs. Basically simple air cooled four-stroke engines are dead.

Strangely a direct injected 2 stroke solves those problems. The BRP Rotax snowmobile engines beat the latest (very tough) US EPA requirements by some margin. They are also lower cost to build, have less weight, make more power and use less fuel than competing 4 strokes. Who knows why we cant have them instead.

 

[autogs]

your forum name should be tangent,every thread off you go on a tangent with no relevence to the original point

 

[Wilsdorf]

The LC engine should have lower metal surface temperatures and so lower Nox emissions. As that's the current bad boy in EU environmental politics they had no choice but to go for a new designs. Basically simple air cooled four-stroke engines are dead.

Strangely a direct injected 2 stroke solves those problems. The BRP Rotax snowmobile engines beat the latest (very tough) US EPA requirements by some margin. They are also lower cost to build, have less weight, make more power and use less fuel than competing 4 strokes. Who knows why we cant have them instead.

Obviously a remap does not need to meet the same emissions as a standard bike (at present - but maybe one day we will have to conform) - but BMW are happily continue with the R1200 twin cam engine in a number of models sans liquid cooling, and still meeting future emissions.