I did not need to trim the levers at all. I trimmed my front brake lever a little only for an old superstion/tradition. I have always had barkbusters on my dirtbikes. I went over there's bars pretty violently one time for no apparent reason. It felt like my brake had stuck on. Checked it found nothing and continued to ride. Not far up the trail it happened again. I blamed the lever getting stuck on the barkbuster as the problem and trimmed the lever. Now all my levers are trimmed. Just call it a personal preference.