What the hell has that chip done to my engine!

I'm new on this board and don't want to be controversial, just helpful, so take my comments in that light. Having made about two years worth of GS-911 and LC-1 exhaust measurements on my dual-spark R1150, I can say with some certainty that any voltage around 370 mV plus/minus will yield the same results. The Motronic "registers" itself to the TPS when you twist the throttle twice after reset. (http://bmwsporttouring.com/ubbthrea...9453&Words=roger+04+rt&Search=true#Post881130)

Every 20 mV of change is only 0.1 degrees, and so from that perspective, even if the Motronic didn't register and learn the throttle position, a 40 mV shift would only be 0.2 degrees (out of 80 degrees full scale).

If someone has altered your throttle stop screws or TPS and you want to get them back in the factory calibrated range, Zero degrees throttle is not 0.0 mV, the Lentini zero=zero is wrong and leads to a too-lean setting. At zero degrees throttle, the TPS, per the Bosch spec, should be set to 250 mV. So if you want to follow the zero=zero process, start at 250 mV.

Here is a thread on some experiments we're running now: http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=895615#Post895615. There is a link in the first post of the thread to the Bosch spec.

RB

Thanks very much Roger, your input is most welcome, need to just set aside a good block time to sort this lot out. I'm coming to the conclusion that the bike is now really fooked up and just needs taking back to baseline.
 
(Please keep in mind that the Motronic MA 2.4 takes 5 minutes with the fuse removed or battery disconnected to reset. For sure, two minutes wasn't long enough in tests I made.)
RB
Thats interesting. I'm currently in Spain with a new to me 1150R and, having tried Steptoe's relay mod, I'm still finding the bike to be rough between 2-3 k rpm - but I only disconnected the fuse for a few seconds so will try a 5 minute removal tomorrow.

Thanks.

R
 
When I bought the bike supplied with it but not fitted was a K&N, decat, end can and a eprom chip.

Ran with the k&n and zorst mods for a while, just before a weekend trip to loch long I reset the tps to 369mv all was well, got great fuel consumption and bike ran well.

Shortly after I plucked up the courage and fitted the eprom chip.
Bike didnt run too well and was back firing on over-run quite alot,
backed of the tps back to 361 in case it was over rich...not really any better.
With the chip in the bike developed a strange noise on WOT in 6th it sound like small stones hitting the sump guard (theres none in there by the way).


So have removed the chip and (for no reason other than noise) stuck the standard end can back on and reset the TPS to 371.

With the chip out its still back firing on over-run doesnt feel quite and right and is still making the same metallic noise as when the chip was in.

Incidentally 2-2.5 glitch is much better now.

The bike is very "fumey" on start up that first puff of smoke is noticable and strong.

1). If the chip was badly programmed could it have damaged the engine?

2). The plugs seem a little heavily contaminated for my liking especially the off side one, which incidentally was missing the rubber cap off the throttle body nozzles (overly lean mixture causing pinking under heavy load).

3). Does the ECU over right the maps of a new chip when the new chip is installed if so can the "maps be purged" and reloaded when the standard chip is installed?


View attachment 262277
- the offending chip

I was answering some questions from later in the thread but wanted to take a moment and go back to the issue of the "non-standard chip".

1) If the chip was badly programmed it isn't likely to damage your engine unless there was a lot of pre-ignition at high power.
2) Not sure if it was overly lean
3) When you put the original chip back in, install the correct coding plug, and reset the Motronic, everything goes back to normal and the "experimental" chip is fully purged.

Making a custom chip for a Closed Loop motorcycle (one with a stock O2 sensor installed and functioning) is much more difficult than meets the eye and with more ways to go wrong. Broadly speaking there are three main types of maps (and up to 8 sets of the three types, selectable by Coding Plug) of the person doing the reprogramming to contend with: Base Fuel Maps, Spark Advance Maps, Correction & Transition Maps.

Spark Advance Maps: On the R1100 and R1150, if one understands the binary values and how to interpret them, a reprogrammer could add or subtract some advance, ride the bike and see what they thought. It would be hard to get an engine brake-dyno though to test the detonation margin. Any changes made to these maps would persist since there are no knock sensors on the Oilheads. On an R1200, if the timing were altered enough to trigger knock-sensor adaptation, the result might be worse timing management than stock.

Base Fuel Maps: These contain injection times based on RPM and TPS angle. Apart from the fact that they are just a starting point whose values get interpolated for RPMs and TPSs that fall between the cells of the table, they get modified by Air Temp, Oil Temp, Barometric Pressure and Battery Voltage. In addition they get modified by short term and long term fuel trims--which is the real issue with fuel changes to a Closed Loop motorcycle. If you add fuel to the cells that are managed by the ECUs Closed Loop algorithms, two bad things happen: 1) The Closed Loop routines return the fueling to stock; and 2) if you add fuel in those Closed Loop areas, corrections get created to remove the fuel and those corrections are applied to the Open Loop areas, for example WOT and high power. PowerCommander understands this problem and on the PC III USB w/Wideband O2 sensor, they do not allow fueling changes in what they believe the Motronic's Closed Loop area is. Home-brew chips don't seem to take the Closed Loop problem into account.

Correction & Transition Maps: These are tables for the Air Temp sensor, Oil Sensor, Barometric sensor, warm-up profiles and for TPS rate of change, and other things of that type. There is no documentation and the info is Bosch/BMW proprietary. Most chip re-programmers "play with" those variables but don't know exactly what they're changing.

Lastly, given that most dyno test runs stress only a handful of the Map Cells near WOT and at high RPM, how much testing can an individual be expected to do? One might see better numbers on the dyno but no tests or data in the range where we do 90% or our riding.

Food for thought.
RB
 
Update....
Left the OEM chip and ECU out of the bike for 48hrs.
Put back together and put the yellow relay back into the CCP.
The bike is now much better and almost pre-chip in feel of running.
Its still back firing on over-run after higher rpm running , so going to try reducing the TPS a few mV to weaken the mixture again a little to see if that cures it. The tinking noise has (I think) gone as well.
 
Update....
Left the OEM chip and ECU out of the bike for 48hrs.
Put back together and put the yellow relay back into the CCP.
The bike is now much better and almost pre-chip in feel of running.
Its still back firing on over-run after higher rpm running , so going to try reducing the TPS a few mV to weaken the mixture again a little to see if that cures it. The tinking noise has (I think) gone as well.

They all do that Sir :)

(and they should, to a degree)

Better to run a fraction too rich than too lean, IMO.

If you go leaner, make sure you keep an eye on the plugs........and enrichen it as required before yo0u burn your valves out.

I'd err on the rich side and enjoy those naughty pops myself, especially in the Dartford tunnel or under a railway bridge ;) :)
 
Since fitting John's latest chip mine's stopped popping on the overrun and it's fast fast fast FAST !!!!

GET ONE!:beerjug:
 
Update....
Left the OEM chip and ECU out of the bike for 48hrs.
Put back together and put the yellow relay back into the CCP.
The bike is now much better and almost pre-chip in feel of running.
Its still back firing on over-run after higher rpm running , so going to try reducing the TPS a few mV to weaken the mixture again a little to see if that cures it. The tinking noise has (I think) gone as well.

I've been working on a project to document the TPS function at small throttle angles. I haven't written up my findings yet but on the 1150 there is no meaningful benefit to changing the TPS voltage a few mV at idle. Here are some tidbits.

-The smallest voltage that the a/d that measures the TPS can resolve is about 20 mV, or about 0.1 degrees. So if you add 10 mV, on average the Motronic won't notice.

-If you add 20 mV, and the Motronic does notice, at idle where the 1150 reports a 0.32 degree throttle opening, you could argue that 0.1 degrees is significant. But at most throttle angles where you operate (5-15 degrees) 0.1 degrees is insignificant.

-To move the TPS 20 mV, you only move the TPS a physical distance at the locking screw of 0.0025" ! Another way to say that even 20 mV is not a significant movement.

-If you do over rotate the TPS to indicate a wider opening than actual, the Motronic will momentarily over-fuel but quickly, closed loop operation will correct the mixture.

-The nominal angle and voltage for the TPS when on the throttle stops are 0.32 degrees and 350 mV. The range of voltages that the Motronic sees as 0.32 degrees is 310 mV to 370 mV, in between those numbers the GS-911 reports the same angle.

There is probably a reason for your popping exhaust but the TPS setting isn't likely to be it. A leaking injector, or exhaust air leak are a couple possibilities.
 
Roger,

From reading your article, I need to up my idle speed as its 900rpm at present so need to check the valves and probably replace the plugs the others are looking ropey.

Just to clarify the backfire is a single 'gunshot' type noise not repetative popping.
 
Roger,

From reading your article, I need to up my idle speed as its 900rpm at present so need to check the valves and probably replace the plugs the others are looking ropey.

Just to clarify the backfire is a single 'gunshot' type noise not repetative popping.

That's the normal backfire with Y piece and standard silencer.

What's not normal is your idle speed, the valve clearance, throttle balance and TPS set to 375 all not being spot on before both chasing a fault or expect the bike to run well with either chip.
 
That's the normal backfire with Y piece and standard silencer.
Thats annoying then, gonna have to be smoother with the throttle instead.

What's not normal is your idle speed, the valve clearance, throttle balance and TPS set to 375 all not being spot on before both chasing a fault or expect the bike to run well with either chip.

Yeah, from reading all the info on this thats the conclusion I've come to, I'm gonna have to get the spanners out. I'm still pretty sure the new chip is a defecticve
On top of my TPS tinkering, someone has altered the brass screws but thankfully the throttle stop screws are still set factory with marker pain in tact.
 
Having just been through all this I would add that the big brass screws should never be more that 2 turns out. If you can't get tickover ok with that then up the voltage slightly and wind them in a bit. Made a huge difference to my single spark especially the popping on overrun
 


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