You can't erase the tune. When they retune your Triumph they are hardcoding a memory chip on the PCM. That tune becomes the default. Your computer takes input from you bike and makes adjustments. So if you have a component that is not running optimally the computer can make minute adjustments using the feedback from the sensors to componsate for those imperfections. Now when you take out your battery all those little adjustments get erased and you are back at square one to whatever tune is loaded. Each vehicle will relearn relatively quickly. I found that my Sprint relearned in just a few rides. It started like garbage and ran super ruff for about 2 minutes then cleared up.
Some scan tools such as the Snap On Modis and the OTC Genisys are 2 way systems and you can overide certain aspects of computer controlled parts like the EGR valve or HVAC systems. Even though you can take control of those parts you cannot change the tune even though those tools are capable of updating a PCM with OE information.
There is lots more but that is the quick version.
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Linear Mode
