Trying to help a friend with a new 2019 Rival what are we missing.

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Running Clone 340 lb & Clone 375 Fri & Sat night low bite racing on Burris 11's that need prepped pretty hard, Tires are real close not the issue can put them on the Triton and run top 3, 1st run Started out on U-Max base line with high cross 70% would not turn at all made some normal adjustments that should of helped it a lot barely saw a difference, 2nd run changed set-up lower cross 61% little better but still a push, 3rd run different driver left lower cross Increased LF camber, Increased RF caster, added rear stagger turned in practice actually rear little free but NO speed NO forward drive, took 2 flats LF camber back out right back to would not turn, ANYONE have similar issues that can give some insight ? I'm going to call J.R. Curtis who I know can help but posted here as well.
 
What numbers did you start out with from the get go?

Cross: 69%
Left 57.2
Nose: 46.3
Camber: LF: .25 RF: 2.75
Castor: LF: 7 RF: 11
Stagger: Front: 1 3/8" Rear: 1"
Pills: LR In RR Out
Right FR toed out 1/16"

Seat back 9.5" off axle
Sr Clone 375 lb, driver 180 lb, 30 lb lead all on seat.

This was on a track where we run all the time ,SAT night racing low grip 11's mid 20's, to 11's mid 30's as night goes on, 1st tried different tires with more bite in them little to NO change.
 
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The guy that owns the chassis is being told this seems common on the New Rival especially with 11's, sounds like they perform better on 33's & 55's
I Guess question is do we need to go out of the box to fix the issue.
 
Both ...one track has sweeping corners wide open track ...other is paper clip tight turns ..was better on sweeping turns track but still had to turn to much from entry to exit
 
What numbers did you start out with from the get go?

Cross: 69%
Left 57.2
Nose: 46.3
Camber: LF: .25 RF: 2.75
Castor: LF: 7 RF: 11
Stagger: Front: 1 3/8" Rear: 1"
Pills: LR In RR Out
Right FR toed out 1/16"

Seat back 9.5" off axle
Sr Clone 375 lb, driver 180 lb, 30 lb lead all on seat.

This was on a track where we run all the time ,SAT night racing low grip 11's mid 20's, to 11's mid 30's as night goes on, 1st tried different tires with more bite in them little to NO change.


I think he may have called me and left me a message but I will answer here as well and will call him back when I get off work.

First thing I would do is drop the cross to 62-64% and change the Left Rear pills to OUT. Get on a tick higher left to 58%. Nose seems to be good with that type of tire. Front stagger needs to be 1 1/2-5/8" and the rear 1 1/4-3/16". RF toe 0 and LF toe 1/16" out. Seat needs to be 9".

The issue you are having is running so much cross on a tire that is so forgiving. I am guessing he is pushing apex off. With his seat height a little higher then normal he is transferring weight to the rf way to quick as he puts any type of wheel input into the kart. Just a little thing to add to the notes....... If youre on a tire punching that soft with a soft side wall, no way you should be that high on cross plus being the pills are IN. You load the rf so quick it has nothing left from the apex off as I like to use the term (Used up the right front). Make sure the rf is setting stock as from factor. I believe it is just the one bigger wheel spacer on the inside, 1/4" on the inside of lf, 3/16" off frame on rr and 1" off frame on lr.

How far is the rs seat strut off the inner motor rail? It should be around 4 3/4"
 
I think he may have called me and left me a message but I will answer here as well and will call him back when I get off work.

First thing I would do is drop the cross to 62-64% and change the Left Rear pills to OUT. Get on a tick higher left to 58%. Nose seems to be good with that type of tire. Front stagger needs to be 1 1/2-5/8" and the rear 1 1/4-3/16". RF toe 0 and LF toe 1/16" out. Seat needs to be 9".

The issue you are having is running so much cross on a tire that is so forgiving. I am guessing he is pushing apex off. With his seat height a little higher then normal he is transferring weight to the rf way to quick as he puts any type of wheel input into the kart. Just a little thing to add to the notes....... If youre on a tire punching that soft with a soft side wall, no way you should be that high on cross plus being the pills are IN. You load the rf so quick it has nothing left from the apex off as I like to use the term (Used up the right front). Make sure the rf is setting stock as from factor. I believe it is just the one bigger wheel spacer on the inside, 1/4" on the inside of lf, 3/16" off frame on rr and 1" off frame on lr.

How far is the rs seat strut off the inner motor rail? It should be around 4 3/4"
I did not call and leave a message I plan to call as I think it will be easier, push started on entry would not turn at all, ONLY ran that much cross BECAUSE Factory told him 70% regardless of tire we figured it would not work.
That info 1st run was a 1/5th mile Tri oval tight turns, Increased rear stagger between runs, decrease RF camber 2 flats NO Difference.

2nd run 1/8th mile Momentum sweeping turns, showed up with less cross 60, left RF camber at 2.5, rest same still 11's this track requires same tires soft 11's with lots of bite, SAME results would not turn, Increased LF camber 2 flats, put tires on that just finished 2nd in clone 340lb with the Triton which helped slightly for the feature still pushing 3th off the leader.

3rd run back to the tri-oval with a different driver racing it who weighs much less lite 65 lbs shorter small upper body, re-scaled moved castor to 10 & 13, 2.5 RF camber, .50 LF camber, 57% left, 47% nose, 60,4% cross, pills LR out, RR in, hot laps it still pushed, increased rear stagger, Increased LF camber 3 flats got ride of push actually little free, No speed No forward drive, for 1st feature took some of the LF camber I added I took back out and right back to pushing and still no forward drive on straights. for 2nd feature added RF camber & LF camber 2 flats, increased rear stagger a little, started out half decent would turn better only lasted a few laps back to pushing and still no forward drive.

So now after know the rest of the story and were already close to your suggestions above, What do you suggest ?
 
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Going back to the 1/8th mile on fri night June 7th for clone 375 lb going to re-scale ahead of time.

Just found out the guy that owns the kart did call you J.R and left the message.
 
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My question is: WHAT kind of track are you running that is requiring Burris 11's and tires in the 20's??? Does it never stop raining?? Where is this track at and what size is it? The Tennessee crowd that runs prepped 33's are killing it on the Rivals. And these are damp tracks. Most of these guys run the 7/15 combo spindles with the Burris tires.
 
There Both here in central Pa, once in a blue moon they will go to soft 33's for later features, one just stays moist slick low bite that is the small 1/8th mile, the 1/5th mile tri oval stays sealed over slick, we feel more confident getting better results on 33's when we can at these places and other tracks that are 33's, but when he runs these 2 tracks it's 11's prepped up hard now some nights the soft 11's are only for the heats then you need harder 11's for the features, We got some good info and have re-scaled and will be testing tomorrow night on 11's, Thanks for the info on the spindles.
And NO it never stops raining but the tracks do not hold that moisture long it runs off, track does not have to stay soft to be 11's.
 
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What happens on low grip tracks with banking is the kart just sits on the LR. You don't have the speed, momentum or grip to transfer off of it. So the kart is lazy and sluggish. Typically momentum tracks, especially flatter tracks, allow enough lateral grip that the higher LS and higher CROSS are the text book setups. But when you have to run sponge tires to get grip, obviously the tracks don't carry the speed or grip to allow that. So throw the text book out the window. You have to change weight, and/or mechanically help the kart to transfer. The RIVAL typically turns well and is considered a free chassis on momentum style high grip tracks. So obviously your numbers need some revising. I would start with less LS weight, possibly in the range of 56-1/2 to 56 on the banked tracks especially. Sometimes something as simple as this suddenly makes the chassis feel completely different. Run a little more air in the lr so your not running flat will help transfer. The RIVAL is very stagger sensitive as well. Sometimes 1/8" will make big changes. I don't think lowering cross much under 65 is the answer since cross helps free the karts roll speed as much as changing your LS in my opinion.
 
Just an update I have been in contact with bricklayer653. He did have a few issues with wheel placement. He has corrected them and is running upfront via text messages he has shared with me.
 
Ya I spoke with him, we still need to find a tenth or two but now it's at least it's reacting to changes so should be good.
Thanks for the help !!
 
My question is: WHAT kind of track are you running that is requiring Burris 11's and tires in the 20's??? Does it never stop raining?? Where is this track at and what size is it? The Tennessee crowd that runs prepped 33's are killing it on the Rivals. And these are damp tracks. Most of these guys run the 7/15 combo spindles with the Burris tires.
We don't even run Burris 11's on my LO206 Rival at Salem when it's a mud hole early in the year.......
 
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