Kart hopping

[Randy541960]

2004 nemisis pavement oval half asphalt half concrete. The kart is hopping when in the concrete corners. Front 46% Left 58% Cross 60% Caster 10&8 Rf camber -2.75 Lf camber +.5 Toe out 1/16 Yellow vega's no prep 9&7 psi. Any recommendations to help free it up? It almost feels like the problem is in the front more?
Thanks in advance Randy

 

[Menace61]

I've never raced pavement. On dirt i have helped two people who had the hop problem. We solved it by reducing the caster and the split. Worked for us right or wrong.

 

[Randy541960]

I will give that a try. It does seem to lead left quite a bit. Reducing the split should help that.
Thanks for the help.

 

[Fast 34]

If its high bite, add left.

 

[Kj26]

Drop the caster to 6/8, raise left to 60, drop cross to 55-56, bump air to 8/10, a touch more nose wouldn’t hurt either.
If you need more close the split up on the caster to 6/6, you can do that at the track without worrying about anything else.

 

[Randy541960]

Thanks for the responses. I will make the suggested changes. I did also find that the seat was too high. Replaced the seat with a Nexgen 2.0. I am sure with all the changes it should be exciting going into turn 1.

 

[racing promotor]

If the seat was way high and the driver has a bigger upper body, the added VCG is probably big part your problem, but I'd also take Kj26 advice and make the other changes.
Good Luck !!

 

[Randy541960]

this might be a dumb question, but does it matter if the cross is adjusted with the front spindle washers or the LR casette adjuster?

 

[Menace61]

No. The LR weight jacker is the way to go though. It won't change your toe or camber like moving washers will.

 

[Randy541960]

Good point! Thanks to all that took the time for help and advice. Much appreciated. I will post results after we hit the track.
Randy

 

[Kj26]

No. The LR weight jacker is the way to go though. It won't change your toe or camber like moving washers will.

HUH ? When did moving washers start changing camber and toe ?
I took the weight jackers outta my Phenoms years ago.

 

[KKania17]

I check my camber 16 times when I scale moving washers. Always moving around on me

 

[Kj26]

I check my camber 16 times when I scale moving washers. Always moving around on me

I just scaled, a 1/2 hour ago, took cross out moved 3 washers on each side, toe didn’t move at all and camber didn’t change enough to worry about.

 

[Menace61]

I check my camber 16 times when I scale moving washers. Always moving around on me

This is what i experience also. If i move more than 2 washers i recheck the toe and camber, sometimes its still good, some times it moves.

 

[PRC01]

Would start at 60% left and go up from there. As far as changing cross, I would adjust with washers. Adjustable cassettes were nice for quick changes, but washers are more consistent.

 

[Corn51]

If you move washers and camber changes wouldn't there be a issue with the king pin? (bent)

 

[Chipg56]

If you move washers and camber changes wouldn't there be a issue with the king pin? (bent)

Yes, hardened king pins are always a little bit off. We mark them and set them in the same spot each time. The only way toe can NOT be affected by moving washers is if you run zero king pin inclination. A half washer or one washer may not make a noticeable difference but moving 3 or 4 sure will.

 

[paulkish]

Which tire or tires are hopping?

 

[Randy541960]

Finally got back to the track and the hop is gone. Now it enters the corner great but has a push from the center through the corner exit.

 

[racing promotor]

Finally got back to the track and the hop is gone. Now it enters the corner great but has a push from the center through the corner exit.

What all did you change ?