I think Yamaha removed the torsion bars a couple of years ago when they offered the free door kits. If I'm not mistaken, they removed the torsion bars and added wheel spacers. I have an 04' and had the doors installed last year, but asked the dealer to leave the torsion bars on because I didn't want to deal with the spacers. I've had zero problems with stability with mine and I haven't really heard of anyone complaining about the bars either on or off. I know this doesn't really answer your question, but I still have mine and I love the ride I have now. Good luck.