DougRaymond
New member
Fascinating discussion, excellent collection and presentation of the data.
I really appreciate your Motronic block diagrams.
I really appreciate your Motronic block diagrams.
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I'm wondering how many 10-20 year old lambda sensors are still functioning properly. It really is a part of the bike that we're blind to. And to make matters worse, not only Re we blind to what it's doing, it is the Motronic most important sensor for good running qualities. If its bad you'll run badly.
Roger and others...
I noticed something interesting on my LC-1 equipped 2001 R1150GS. I have Lambda set at .94 (13.8:1 AFR). As long as I ride below 4000 rpms the engine hovers right around 13.8 on level going and modest uphills. However, above 4000 rpm the AFR goes up to 14.4 on level going while maintaining steady speed. If I increase throttle enough for the engine to pull a little, the AFR drops back to 13.8.
I've ridden several hundred miles, so I wouldn't think the Motronic is still learning. And even if it was, I would expect steady speed on level going to be running in closed loop, which should be 13.8. I've observed the above pattern in gears 1, 2 & 3. I'll need to get on a bigger highway to test it out in the upper gears.
Could it be that the Motronic is designed to lean out the mixture when it thinks the bike is cruising (steady throttle, above 4000 rpms)? I have no way of knowing for certain when the bike is in closed vs. open loop, since the only feedback I'm getting is the AFR gauge.
Roger, I was away for a few days but now back home, and as soon as the weather clears I'll get out for more runs and will log data using LogWorks3.
By "small-TPS-angle" do you mean small differences up or down from current speed? My experience was at steady throttle above 4000 rpm on level going the AFR would drop to 14.4, and I experienced just what you describe, as if the Motronic cut off the the fuel completely but then decided not to, all in a split second. Not a big "surge", but detectable. Below 4000 rpm when the AFR is at 13.8 at steady throttle I didn't notice the problem.
I'm relieved to know you observed the same pattern on your RT - it assures me I wasn't just imagining this! Any guesses about why the Motronic is programmed this way?