Just to clarify - as I think we are talking about different things with respect to the 12 min tune -
@Wajhi was installing a custom map obtained from another member that had been tuned to match his configuration - it was a map configured for
NO O2 sensor; I advised that 12 minute tune is not applicable when the O2 sensor is not in play - that is the whole point of the 12 min tune, to trim based on what the O2 sensor sees (and if the O2 sensor IS in play, it will counter against any fueling changes in the map, which is why it is disabled). Now clearly there is no bike-specific trim available without going to an actual tuner - what I advised is that a 12 min tune will do NOTHING when the O2 sensor is disabled (i.e. on the map he was going to run)
Now - to get perfection, then it would HAVE to be dyno- analyzed and trimmed. Whether this is necessary or required would be up to the user. For many, maps developed on other specific machines are often quite close and satisfactory (good enough) as is.
Now that I can't agree with - every bike that leaves the factory has the same exact equipment and map (within any given generation anyway) and the very purpose of the 'the 12 min tune' (which is nothing more than a forced adaption to speed up the ever ongoing trim process) accounts for those bike to bike differences by trimming for not only the variances but other local conditions, including the gas itself. Is it 'Tuning' ? No, but it IS trimming - Is it necessary? Typically YES. Snake Oil? No.