Depends on how much you want to do

I had to buy a special 4-prong socket to replace the clutch on my Honda, helps to use an impact wrench for that as well. Not sure about Suzuki specific stuff, I only have a Triumph right now, and I haven't had to do any major repairs or maintenance yet - and besides, it's still under warranty. I just like adding stuff to the outside
One thing that is REALLY handy if you take the rear wheel off for any reason is a chain alignment tool. Looks easy enough to build I suppose, but I bought one. Here's a link to what it looks like:
http://www.motorcycle-superstore.com/2/9/205/4876/ITEM/Motion-Pro-Chain-Alignment-Tool.aspx
Depending on storage space and what kind of riding you do, it's nice to have at least some basic tools on board. If going on long rides in the middle of nowhere tire tools, patches, and an air pump are a good idea as well. And be sure you remember a wrench large enough to do the axle bolts.