PA1195
Well-known member
PLease don't mistake my post as being a "wet blanket" as another has inferred. My question is whether or not the Motty can be proven capable of quickly maintaining a pre-determined closed loop A/F ratio, versus a preset added or subtracted fuel matrix value as with the PCIII. The PCIII's map is really only good for the conditions under which it was originally determined, as it's a non-learning open loop device.I'm not sure what that would prove. The mods change airflow and require changes in fueling to be fully effective (and sometimes to prevent damage to the engine). Differences between with and without the Motty's adjustments to fueling wouldn't prove anything about the Motty itself. A PCIII could be tuned to the exact same AFR targets and get the same resulting power. The Motty being better than other fuel tuning systems doesn't necessarily give more power; it just continuously maintains the AFR targets that you set regardless of seasonal changes, exhaust/intake changes, etc. Something like a PCIII would require dyno tuning to account for these changes.Fun deal all around and bunch of interesting mods. Congrats on the hard work. I'd be curious to see back to back runs with the Motty programmed to dupe the Factory A/F ratios as sensed by the pipe probe, and at your 13.2 as currently set up. Same day/same air density. Let's get the Motty out of the picture, and any remaining assumed benefits would then be from the other experiments. The real sell for me at least would be an improved fuel controller, which the Motty appears to be.
Gary in Fairbanks
An optimum A/F ratio - as in the 13.2:1 you selected for your road tests, should make more power than a leaner setting if the device can keep up with the data flow and fuel metering. How much additional power, if any, can be produced is my question. That's all I asked. As for the other suck and blow mods, well, I'm sure they helped but not all may be willing to modify their bike in a like manner. However many, including myself, may be interested in having a couple of A/F settings readily available in a closed loop controller that's capable of smoothly controlling the bike's A/F ratio for different riding conditions.
The best place for all this of course is a controlled series of dyno runs yielding actual rear wheel HP/torque/A/F ratios, not the highway. Admittedly time consuming and expensive. But regardless of the actual results, I find your work interesting and worthwhile.
Gary in Fairbanks
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