I bought a 2001 KXR last December 2017. It has many mods. It has 2" lowering springs. Looks great, but spring bottoms out on larger sharp bumps. What springs would work better? Maybe 1 1/2" drop instead of 2".

 

My first thought would be, "Slow down for large sharp bumps." Beyond that I think you answered your own question. If you want more ground clearance go with a coil with less drop. You might also just add spacers on the spring seat until you get what you want. An alternative would be an adjustable shock (coilover) where you could dial in a firmer bump ($$$).

 

It is best to start with numbers. Go to jagrepair.com and find the vehicle spec book for the proper/original ride height.

Obviously, with the springs already lowering your car, it is hard to know for sure, but it is possible your ride height is even worse because of a collapsed upper shock mount. Replacing a failed mount will restore some height and maybe leave everything in "good enough" state. Check from within the engine compartment for bits of foam around the shock tower. Check that the shock is well centered in the opening, too. Keep in mind the stock part is of poor design and will fail sooner or later...

On the other side, due to this suspension design, ride height dictates camber. Any lowering for any reason (short/sagging spring, collapsed joint, etc.) will make camber go more and more negative (top of the wheel tucked in more and more), with associated tire wear. So, the only "correct" answer is to go back to stock ride height. As they say, it is all about compromise, basically how much tire wear you are willing to sacrifice for that lowered look.

Best of luck, keep us posted.