I use my old (1995) trackmagic shifterkart for autocross with a Kawi drivetrain. I cannot keep up with anyone at events. All my buddies say that the chassis is “just too old”. My question is: Can you go in and weld in gussets at the tubing welds to stiffen up the chassis and make it “fast”?
Karts are designed to flex a specific way and once the tubing gets a lot of track time on it, it simply isn’t going to flex as it is supposed to anymore. I highly doubt welding gussets in will bring it back to life. I think if anything you’re going to make it worse.