How important is a LF-RR weight match

alvin l nunley

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I have heard many times about the importance of keeping the LF and RR corner weights close. Just how important is it?
The reason I ask is I’ve found a way to keep them “identical”. You do lose some things. Like control of the left side % and the cross %. You have some, but not complete. You still have control of the front percentage. Truth is; you can’t control everything. If it’s good to have those corners the same, you have to give up something.
And this works with any “Total Kart & Driver” weight. In fact you can change the Total Weight to anything you want and all the percentages stay the same.
Al, my approach has always been that setup is an engineering exercise, and anything in engineering is a compromise, just that the compromise(s) go un-noticed if what is given up is not something that seems important to that endeavor. With that in mind, I start with the chassis builder's (and/or local dealer's)recommendations for basic setup on percentages, castor and camber (or absent that, a generic set of values I've used for years) and adjust from there, using driver input on how the kart feels, my observation of what the kart looks like it's doing versus what the driver says he/she feels, and lap times as my guides. If we get good handling with LF/RR weights that are close, fine, if not, that's fine too. However, being lazy in my data recording, I just put down total weight and the percentages for front, left and cross, make any necessary adjustments and record the final stats, paying little/no attention to actual corner weights. Now you've got me curious, so the next time we scale the kart, I'll pay more attention with regard to whether the LF/RR corner weights are close or not, and whether necessary changes bring them closer or farther apart. At the tracks we run at I would definitely feel the need to have pretty good control over left side (though I seldom need to change it) and cross over the long haul - old habits die hard, lol.
I like to keep the lf and rr somewhere close to each other..
I have a kart that likes the lf, rf,rr exactly the same. Karts very good bout anywhere
we race asphalt ( oval ) and were finding out that our RR, LF, weights are very close also, within a pound or two and from a driving standpoint i feel more confident that the front has more grip and is to my liking.... i think the weights were 84 lf, and 83 rr...
I don't know how important LF/RR are. I don't worry about RR. Just Frt/X/Lf.
BUT after I set up yesterday using Al's program my LF/RR are within .4lbs of each other.
If that helps.

Thanks to Al for his Setup Excel program.
On a balanced kart, the LF, and RR weigh the same. Or the LS percentage is equal to your rear percentage.
This worked well on older karts, but not so much todays karts. I do not worry at all what the wheel weights are, if my percentages are correct, then my wheel weights have to be also.