It comes down to if you are breaking the law. If you go breaking the law, sooner or later you might get some heat on you. Don't break the law, it's not a guarantee of being left alone but your chances of being hassled by cops drop dramatically.
Its like with 'hooning'. Like it or not, burnouts, drag racing and so forth are illegal. The laws on these are unlikely to get changed n the forseeable future. Same goes with illegal/non-engineered modifications. If these are on your car, and you know they aren't legit, get pinged - tough.
A few biker gangs are probably peaceful and law abiding. But I'd say most aren't, at least the ones made public. But if you are bikers part of an incorporated club, then you are very much more legit, for there are various protocols you need to follow.