I have never been a fan of how the gen 1 handled. I have had the bike since it was new and never got use to how it felt in corners and how twitchy it felt at other times, the bike just felt loose. New tires helped, suspension set up for my weight helped but nothing completely solved the problems. I hated the bike on the track. It became even more apparent how bad it handled riding it after my track bike.
I removed the 3mm shim for the rear shock and with the increased trail it wasn't so twitchy but you had to fight it in the corners. So at this point the bike was on the chopping block. Than the ass fell out of the economy and I knew I wouldn't be able to sell it for a decent price. So I decided to play around with the shims on the rear shock again. I installed the 3mm shim again just to be sure it wasn't me, yep it handled like sh*t. I took the bike out and it would fall into the corners and wallow through the sweepers.
So now I had to find some shims, Kawi sells them for over a $100,
now there was no way I was going to pay that for some freakin' washers. So I googled 17x32x1 and there it was, a washer for a Suzuki DRZ400(09181-17019) part of the kick starter. I ordered three and installed only one on the bike. It handles better than my track bike now. I cannot tell how well this bike handles with the 1mm shim installed. I don't know how anyone thought it handled well with the stock settings,
more power to you. It now feels like a completely different bike, the bike turns with little effort and tracks through sweepers like it is on rails. Transitions from right to left are effortless. So for a couple of bucks and an hour of my time I have a new bike.