They have been known to scan ECU's for modified tunes, and some assume would use that info to deny warranty work. But in the US they cannot do that unless the modified tune can be proven responsible for the repairs you need. So in example if the shock absorbers are soft after 250 miles, that tune that gives you 300 horsepower is of no effect. There could be emission issues for wanting you to keep their tune, but it's still your bike, and if you want to change it and are able to change it, it is yours to do, though you may assume a certain amount of risk. I've done mine, and everybody and his brother have done theirs! Some with dealer help so.......tune early, and tune often!