How does castor affect a kart??

[Matt]

I understand camber and toe and what they can do to affect chassis handling but I can't really seem to wrap my head around how exactly castor would affect it. I know what castor is and how it's adjusted but does it have any effect on the tire wear or handling of the chassis at all?

[JET Karting - Andy Finke]

Castor adds weight jacking to the front end, therefore adding grip.

While I've added castor sometimes sprint racing, most times you are tempted to do it, you should take grip away from the rear. Especially true if you are local racing. National racing puts so much rubber down you can sometimes add castor to deal with it.

Road Racing you run as little castor as you can drive to help lessen the drag through the long corners.


Andy

[Jeff Stamper]

Adding caster to the front tilts the kingpins back, and when you do that you will make the inside wheel push down into the track when you turn. When it pushes down, it tries to lift the inside rear off the ground. That will let the kart rotate through the turn. There are varying thoughts on whats too much and not enough. If you do what Andy says, you may end up with a kart thats too loose on entry. I am not saying he is right or wrong, but its mostly a conditional thing. You also have to remember that when you gain on something, you will more than likely lose on another, so its a fine line on adjustments.

[Rick]

If you do what Andy says, you may end up with a kart thats too loose on entry.

Which thing are you specifically referring to? Running little caster, adding caster or removing rear grip?

The reason I ask is because my shifter is pretty loose compared to my TAG. I think this is due primarily to the power. So I am trying to get more grip in the rear.

FYI, I have minimum caster on my kart right now and it turns in fine.

[Jeff Stamper]

Well as an experiment this Spring, I took out all the caster on my kart. Its almost undrivable ! It makes the back end very snap loose ! It seems to go into the corner very good, but all of a sudden it will snap loose in the back. It also makes it very loose on exit. I hope that helps. This season I now have access to scales so I can do some experimenting. I hope to learn a lot and help make the Prokup brothers very fast by the end of the season. And maybe somewhere along the line, I can gain a tenth or two for myself !!:clap: