Thoughts on Chassis Setup

This isn't really a nuts and bolts blog on chassis tuning per say, this is a blog on the philosophy of chassis tuning and some thoughts on driving. I think there are a lot of misconceptions on chassis tuning. Racers expect straight answers to their chassis handling woes and think there are perfect answers to "my karts tight" or "the kart's slow". The problem is no one knows the answer to either question but if you do this stuff long enough you get better and better at guessing! That's right, it's just trial and error and a lot of (hopefully educated) guess work.

The one thing to keep in mind when you have a handling issue is what seems obvious as the culprit might just be a symptom of another chassis setting issue. So you have a push, you go stiffer on the front bar and it's better, you might add a little positive camber and it's better, you move 5 pounds and it's better, you widen the rear out to take away some grip from the back of the kart and it's better but you still have something of a push. You made four changes to the kart but you still have a push. What's this tell me? That you haven't actually fixed the underlying issue with your chassis setup. Maybe the seat needs moved forward, maybe the ride height is the issue, maybe the front is too narrow or the wrong axle is in the kart. There's a lot of things it could be but when I make changes to the kart and I don't really fix the underlying handling issue then I assume whatever I am changing is probably not the actual issue hurting the handling of the kart. Many times I'm better off to put the other changes back to where I had them and fix the *actual* handling issue instead of crutching the setup with changes that didn't really fix the main issue anyway.

Another issue is bad feedback from the driver or if you are the driver/mechanic not paying enough attention to the kart while you are on track. Many times I'm told that the kart is loose but looking at the kart the front tires are grained and from watching the kart on track and watching the drivers hands the kart only looked loose on the exit of the corner. After you talk to the driver some more about what the kart does on entry, middle of the corner and exit you find out the kart pushes on entry then its loose on the exit of the corner. So if you try to tighten the rear of the kart you will actually make the entry push worse which will make the exit worse since the driver will have to turn the wheel even more on entry. The underlying issue is entry push and a symptom of that is the kart getting loose on exit because the driver has to turn the wheel too much on the entry of the corner. Many times the first thing a driver notices about the kart might not be the main issue but a symptom of another setup problem. Asking the right questions, looking at the tires and watching the kart on track will help you decipher the chassis better.

Of course none of this matters if the driver isn't running the proper line, overdriving the kart on entry, not using enough brake or the inverse, slowing down too much and not carrying speed. Many setup issues are driver induced. One of the best "handling fixes" out there is to put a more experienced driver in your kart for a few laps. Either the driver will confirm that the kart is poorly handling and can probably offer some helpful setup advice or they might crack off a great lap time and you know that more driver training is in order. Surprisingly I have seen drivers refuse to put someone else in their kart. Personally, knowing where the problem lies is more important to me than any ego bruising that may occur. It's even better when you have data that you can overlay after the fact and see where the other driver is making time on the track and what you need to do to improve, that's why I'm a big fan of the Mychron GPS or E-Box. Going over a GoPro Camera video with an experienced driver can also help you fix some driving issues.

Another option is to hire a driving coach for the day. We do a lot of schools at New Castle Motorsports Park and I'm always amazed at how well the drivers do after the class. In many cases it's "seconds" for newer karters. Having someone who can show you exactly how you should drive through a corner, where to brake and apply throttle and keep making you do the same thing lap after lap makes a huge difference. Once you "get it", then you can build on your results from there.

Hopefully this blog helps give you more food for thought and ultimately reach your goals in karting, which is what it is all about!

Mark Dismore Jr.
Comet Kart Sales