This is a good question bro, and one that can't be answered with certainty without some experimenting. A lot of times, guys that are very lean, have smaller frames and bone structure. Lower rep ranges can possibly cause some serious damage and injury to someone like this. Instead of always trying to add more weight, it can be much safer to add more reps. Lets take incline DB presses for instance. If you are able to press the 90's for 8 hard reps, while using good form, instead of moving to the 100's, I would increase resistance by adding more reps. If you can lean to press the 90's for 15 reps, and your diet in on point, there is a good chance you will grow. Once you can reach 15 reps, using tight form, move up in weight.
Also, for everything you do, make sure you are making the weight HARD. You can get a lot out of less weight, if you make the weight hard. Squeeze the muscle you intend to work. Don't let yourself rest at the top or bottom of the movement. Keep tention on the muscle through the whole set.
If you aren't already, use squats and deadlifts to build a thicker body. Keep the weight under control at all times and don't worry about the lbs you use. If BB is your goal, it doesn't matter how much you can lift. It's about what you get out of the exercise.