Cross VS Stagger

Festus

New member
Paul. Usually run the same small bullring type track. Every once in a while I have seen our normal lap times seem off & our rpm go down some. Could this be when I had prepped the RR tire a bunch? I have had a racer tell me my LR tire shouldn't be prepped near as much as the RR. Since I am just learning I was prepping the RR a lot more aggressive than the LR. Nothing wrong with the way you write..... its just over my head 😎
 

flattop1

Dawg 89
Something just popped in my head . Stagger matching the track radius .
How about stagger matching what the chassis is doing in the turn .
You could be turning from top to bottom not following the turn radius at all .
 

paulkish

old fart
Every once in a while I have seen our normal lap times seem off & our rpm go down some.
Including your thought about prepping ...

thunk on this... you got this BIG RR tire and you throw grip to it via prepping.
... are you not also making it better at rolling where it might want to roll instead of where you might want it to roll?
... so you get it to still turn(you ain't pushing) don't you have to grip with the fronts to be able to force the tire which now wants to much better roll straight ... turn?

Anytime your on the track your either rolling at the same speed, slowing down or accelerating ain't you>?

And then you turn.

If your rolling into and thru the whole turn at the same speed get the LR off the ground, put just enough grip at the RR so it does not slide out on you and the turning fronts rolling with camber gain at the RF and camber loss at the LF along with ackerman roll you thru the turn.

Butt that ain't going to happen because you cannot move/transfer all the weight off the LR to the front leaving a minimum at the RR.

So?????? Because of it's just the way it is you have to carry more weight in the back then would be perfect.

That's where stagger comes in it allows you to carry more weight more efficiently at the back.

Stagger lets you roll more weight in the back better thru the turn by letting weight that must go to the right and to the RR roll around your ruddered, pinned or breaking LR tire when slowing down.

Then when you start accelerating you still only need enough weight on the RR so it can out accelerate the still rudder or pinned/gripping LR tire.

The real good of it if you get it done right is you can also start your acceleration on your griping LR small low gear tire.
The neat part of it is needing to accelerate also matches up to not turning so much and because your not turning so much you are able to collect some weight to the LR off the RR and front so hopefully your RR now only has enough grip on it that's needed for it's bigger diameter to out accelerate the LR.

It ends up the straighter you get going the more weight leaves the RR and I know it's hard to believe but your now mainly slipping the RR.
And even if your not all that BIG RR now is doing is wanting to go straight!~ /// ... and "so what" that's the direction you want to go on the straight anyway. ... :)

Hardest thing on an engine anywhere on the track is when your horse jockey has their foot to the floor and track grip along with turning left forces it into reduced rpm's because track grip slows what your racing.
It's also the hardest/worst situation for an engine to recover from.

So ... sure over prepping your RR might with the right conditions suck the life out of your engine and lap times.

... maybe ??????? ... :)
 

"J'-remy

Member
Stagger on the front is irreverent. because the two front tires are not on a fixed axle it wll not force the kart to turn . the chassis manufactures need you to run 'stagger' on the front because the frame is built with different axle heights to accommodate the extreme differences in tire diameter between the left and right. rear stagger should be a compromise between getting around the corner and scrubbing speed down the strait. if you have your stagger matching the radius of the corner you are scrubbing too much speed in the strait.
 

XXX#40

2A supporter
Stagger on the front is irreverent. because the two front tires are not on a fixed axle it wll not force the kart to turn . the chassis manufactures need you to run 'stagger' on the front because the frame is built with different axle heights to accommodate the extreme differences in tire diameter between the left and right. rear stagger should be a compromise between getting around the corner and scrubbing speed down the strait. if you have your stagger matching the radius of the corner you are scrubbing too much speed in the strait.
Wrong on both takes
 

jaymancds

Premium User
Wrong on both takes
For his stagger on the front, he is correct. Front stagger does little more than affect cross and ride height.

Source: Mike from Hyper Racing on their FAQ page. "Because front tires rotate independently, unlike the rear tires, the difference in circumference (stagger) will only change the ride height, it will not make the car turn"
 

alvin l nunley

Premium User
Rear stagger should be set to match the path the kart takes around the corner! It can be calculated.

To calculate it takes several pieces of information, not the least of which is the turn radius, the track length and width.

Like has been pointed out, stagger is sometimes a compromise between the length of the straightaway and the radius of the turns.

My, "free for the asking" program called Nine Sheets,, amongst its 44 pages, has 2 pages (metric decimal) on calculating stagger. Only a guide, but pretty close. It's a proven fact that, a rolling tire has more traction than a sliding tire, the closer your stagger, the better chance that both tires are rolling.

My personal belief, front stagger has no useful purpose other than to get the corner weights close.
 

flattop1

Dawg 89
For his stagger on the front, he is correct. Front stagger does little more than affect cross and ride height.

Source: Mike from Hyper Racing on their FAQ page. "Because front tires rotate independently, unlike the rear tires, the difference in circumference (stagger) will only change the ride height, it will not make the car turn"
Provided there is no caster or camber involved or steering input .
One thing that's said ; only affects ride height . Brings the question ? Does ride height affect anything ?
A sprung chassis make any difference ?
 
Last edited:

paulkish

old fart
Won't having a bigger tire on the right front all by itself Help it turn...
Because a bigger tire has more inertia which will make it roll around the smaller tire with less potential ?
Answer: Yes

... :)

It does not apply go the rear tires because their tied together by the axle and act a a single unit relying a a difference in grip to turn.
Simply reduce the difference in grip and they'll roll straighter no matter what the difference in roll out.

... :).
 

XXX#40

2A supporter
For his stagger on the front, he is correct. Front stagger does little more than affect cross and ride height.

Source: Mike from Hyper Racing on their FAQ page. "Because front tires rotate independently, unlike the rear tires, the difference in circumference (stagger) will only change the ride height, it will not make the car turn"
Chassis rake and weight transfer, so no he isn't entirely correct and no they arent welded to the chassis at extreme height differences
 

jaymancds

Premium User
Provided there is no caster or camber involved or steering input .
One thing that's said ; only affects ride height . Brings the question ? Does ride height affect anything ?
A sprung chassis make any difference ?
I dont think a sprung chassis would make any difference. The only difference in this case is how the weight is transferred, but either way it transfers. Now with that said, the micro sprint/and I assume full size sprint cars run a very low cross 45-50% and rely on a ton of stagger and dynamic loading to make it do what it does. But with all that said, I feel like the principle still applies the same, stagger only helps because both rear tires are turning the same rpms, while the fronts can spin independent of each other.

I think ride height affects things, I just dont yet know what it affects more than how the body hits the surface. I can make some hypotheses about what I think it would affect but it would just be guessing.

Chassis rake and weight transfer, so no he isn't entirely correct and no they arent welded to the chassis at extreme height differences
I didnt say they were welded differently, but that he was correct with saying that front stagger doesn't make the kart turn.
 

Festus

New member
What would happen if the rear axle was cut in half. Add 2 more bearings & another brake rotor/caliper setup? Assuming chain drive on right side. Could both rear tires be the same size now? Just curious
 

95 shaw

Premium User
What would happen if the rear axle was cut in half. Add 2 more bearings & another brake rotor/caliper setup? Assuming chain drive on right side. Could both rear tires be the same size now? Just curious
Provided you have some sort of differential, and could control which wheel power goes to, yes.

Drive a one wheel wonder yard kart. It becomes evident that when weight is lifted off the drive wheel, the kart slows.

Stagger is about pushing the front left as much as it is about rolling the rear axle around the corners.
 

Ted Hamilton

Design Drafter / Racer
The vehicles I started racing with were on 1/10 mi. asphalt oval, LR drive only, 2x2 wooden main frame with a full body. We could flex them hard enough to pick that wheel up, and yes, loss of drive. So if you're on an oval and want single wheel drive, make it the outside wheel, for sure.

The ONLY benefits I see to stagger are helping with turn-in and reducing corner scrub. If the track is tacky enough to allow for turn-in without it, it's also tacky enough to unweight the LR enough to run without it. If you can make a kart bicycle, there's enough grip not to need stagger. If it's dry slick, you'd better have some. But don't take our word for it -- go test. Learn. Find a new way. Find a better mousetrap.

It has never made sense to me to over-tire a kart and then remove grip... Give me all the grip I can get and then let me tune and drive to compensate... A bunch of weird work-arounds seem to exist in dirt oval karting that could be solved by more appropriate means, IMO. But by all means, follow the existing status quo from the established leaders. Just keep in mind you'll have to do SOMETHING different to beat the people who are establishing the status quo... Question and reason out everything. I will say that with the amount of weight on a kart, going purely straight, there's no way you can "drive off the left" down the straight, and "drive off the right" in the turns. The "right" is slightly more accurate, but only because of dynamic weight transfer. I'd wager a bit that BOTH tires are in a controlled slip in the turns, and modern LTO karts NEVER go purely straight. So, driving a big ellipse means that they're always living in some part of dynamic weight transfer, and thus you can get away with some amount of stagger. I don't think most people have tested enough to truly optimize every factor.
 

jaymancds

Premium User
The vehicles I started racing with were on 1/10 mi. asphalt oval, LR drive only, 2x2 wooden main frame with a full body. We could flex them hard enough to pick that wheel up, and yes, loss of drive. So if you're on an oval and want single wheel drive, make it the outside wheel, for sure.

The ONLY benefits I see to stagger are helping with turn-in and reducing corner scrub. If the track is tacky enough to allow for turn-in without it, it's also tacky enough to unweight the LR enough to run without it. If you can make a kart bicycle, there's enough grip not to need stagger. If it's dry slick, you'd better have some. But don't take our word for it -- go test. Learn. Find a new way. Find a better mousetrap.

It has never made sense to me to over-tire a kart and then remove grip... Give me all the grip I can get and then let me tune and drive to compensate... A bunch of weird work-arounds seem to exist in dirt oval karting that could be solved by more appropriate means, IMO. But by all means, follow the existing status quo from the established leaders. Just keep in mind you'll have to do SOMETHING different to beat the people who are establishing the status quo... Question and reason out everything. I will say that with the amount of weight on a kart, going purely straight, there's no way you can "drive off the left" down the straight, and "drive off the right" in the turns. The "right" is slightly more accurate, but only because of dynamic weight transfer. I'd wager a bit that BOTH tires are in a controlled slip in the turns, and modern LTO karts NEVER go purely straight. So, driving a big ellipse means that they're always living in some part of dynamic weight transfer, and thus you can get away with some amount of stagger. I don't think most people have tested enough to truly optimize every factor.
Personally, I would love to rent a track for a couple of days AFTER a race day. Left the way that it was, and just kept tacky. I would love to spend days testing, making a small adjustment and running a few laps, learning what it did, etc. The problem with that is the track needs all the time they can get to be ready for the next race, my local track has to have EMS on site for insurance if anyone is on the track, etc etc. Testing is expensive and most of us dont want to risk being wrong on a race night.

It would be great if I could go out with something different on the kart for the heat race, but if it doesnt work, then I'm buried to start the feature.
 

alvin l nunley

Premium User
It has never made sense to me to over-tire a kart and then remove grip... Give me all the grip I can get and then let me tune and drive to compensate... A bunch of weird work-arounds seem to exist in dirt oval karting that could be solved by more appropriate means, IMO.
My feelings exactly!!!
 
Top