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Old 12-19-2011, 06:59 PM   #23
roger 04 rt OP
Beastly Adventurer
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Joined: Nov 2011
Location: Massachusetts
Oddometer: 2,370
Two Test Rides

Over the last two days I've put a few hours on the bike. I have to say, that the slight downward shift of Closed Loop Lambda (AFR) from 1.000 to 0.965, has made a remarkable change in smoothness and low-end power. There has not been any sense of hesitation, in fact quite the opposite. I'm now running RPMs between 2500 and 3500 around town, even in 5th gear.

As far as the Motronic ECU is concerned the data looks like this:

Total data points: 4,000
Percent Closed Loop: 45% (same as before for the local conditions)
Average Closed Loop Lambda Voltage: 410 mV (right where expected, indicating good loop closing)

The new shift plots are looking the same as the earlier stock sensor plots. The big difference being the improved performance and the AFR meter reading 14.2:1 +/-. The above also indicates that the Motronic has been "convinced" to accept the programmable O2 setting and doesn't know that I've richened Closed Loop Lambda.

The next tests will be on the highway.

There are several variables still to tuned:

High Lambda Voltage: (800 mV to 1V)
Low Lambda Voltage: (0V to 200mV)
Low Lambda Value: (how far below the 0.965 mid-point)
High Lambda Value: (how much above the 0.965 mid-point)
Target Lambda: (is there a better target that 0.965, implied AFR 14.2)

Filter Sensor inputs?
Monitor Sensor waveform.

In spite of what needs to be evaluated still, it looks to me like a slightly lower Lambda target (richer AFR) makes a MUCH smoother bike.

Will post up some charts later.
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