How I Tune My Kart At The Track
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- เผยแพร่เมื่อ 20 เม.ย. 2021
- I've had some request about how to tune a kart chassis at the track. Well, right or wrong, this is how I do it and the things I look at. I'm also a firm believer in having a good baseline to start from and go back to. Watch and let me know if you have more questions.
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#dirttrackracing #kartracing #dirttrack #racerguy
Hey man, thanks for the info. I’m new to all this so about 80% went over my head haha but I guess the further I get into it all I can come back and gather more info.
Don't worry I believe 79.0000% of it was bullshit so I doubt you missed anything.
Great video!
Thank you!
You talked about changing the rear roll center. Did you raise both the right rear and left rear together, or did you just raise the right side?
I would recommend keeping the LS and RS equal. Remember your ring gear is located on the axle and angles on it can easily help throw the chain. Keeping that chain lined up comes first to me. I have ran it on a slight angle on my 500, but I didn't really see any advantage.
Also since there's no suspension on these karts there really is no roll center, its really probably an instant center. But me being a stock car guy, I'm going to still call it a roll center hahaha. Just like I'm going to call these engines, motors!
Why are the right side tires so much wider than the left sides?
That's just what most everyone runs on those speedway/flat style karts to maximize grip and reduce roll speed. Most of those kart classes don't have a lot of hp. So anything to reduce drag is the thinking behind it. Outlaw karts run more of a sprint car style setup on tires. But they also run a lot more degrees of yaw angle and of course have a higher power to weight ratio.
So I see high cross karts use backwards cross. How do you work with that? I noticed you said you follow the normal standard in racing more is push less cross of more steering.
The only thing I can say is not to over complicate it. It's all about which tire is loaded and how much. Make one change at a time and write it down. A race car is like a teeter totter. Whatever you do to one end of it equally effects the opposite side. You need to find the balance that you or your driver is comfortable with. And then how to adjust your car to the track and conditions. The main thing is, whether you are moving weight, changing wheel spacers, RH's, whatever, know what your wheel loads are. Most numbers you are going to come across from builders, friends etc. are just starting points anyways. It's all about the fine tuning that picks up those 2-3 tenths that everyone is chasing. Hope that helps!
How much do you move the RR Or LR in or out incrementally? What is the total your willing to move each before moving to something else?
I usually move at 1/2" increments. Unless it's really far off, I might start at 1." If you don't have any adjustment left you need to change somewhere else. Also just keep an eye on you alignment front to rear. The way the RF and RR line up also effect the handling a lot.
1/4" on either rear hub is a gigantic change as far as feel. I've never moved more than that in a weekend because if you're moving hubs that much there's other issues like wrong tires, too much caster, wrong air, something is bent.
@@chafeeracin611 Not for me. If I go to a new track, or racing a new chassis, or both, I'll give the car what it ask for to get it working. I think moving a hub 1/4 inch is really a fine tune adjustment. But I do think after running a chassis for a while you learn what it needs and likes and what to change to get it working. And the same with a driver. They all like different things to go fast. Just my opinion anyways.
@chafeeracin611
Damn right that is a big change.
What pressure did you run in your tyres?
It's been a little while. I believe it was 4lb LS, 6lb RS as a basic baseline. Then I would adjust from there.
@@racerguy9483 Thank you, I'll give it a go next race and see if the times go down.
I ran 4-5 lbs left and 5-6 right. Sometimes I’ll bump up rr and lf pressure depending on conditions. You can also use your gears to alter the handling of a kart.
@@lewisr993 Yeah that sounds really close to what I ran as well. I would change RR on the Outlaw Kart all the time to mostly adjust corner entry. I never used gear for handling though. I always just thought of gear to accelerate off the corner and straightaway speed.
How do know what gear to use
So just started flat kart jr stock
We have 212 Predator
The main thing is having a tach and dyno sheet, and knowing the torque curve on your engine. But just starting out and running Predator you are probably not going to not have access to a dyno sheet and probably need to use the test and guess option, which is perfectly fine. These karts are very dependent on gear and it needs to be right. But I find I need enough gear to pull all the way down the straightaway to have enough speed. You want to hit your top rpm at the end of the straights if possible. But track conditions, shape, and starting pos. can all effect gear choice depending on what you need. Everything on a race car is always an educated guess for me. My biggest advice is guess the best you can and the more experience you have the better your guesses will be. I've only ran a predator once, but I believe they run 5500- 6000ish? I may be wrong but I know it's less than a clone.
@@racerguy9483 thanks we will give it a go
How do you know how set air pressure
Do you mean for a baseline? Or to adjust handling? Or both? I usually start with what my chassis builder recommends, then adjust from there to what I think the kart and tires need. Short answer, trial and error. But air pressure is the only spring rate adjustment you have on a kart.
Tire pressure can be weird, 1/2 psi can move 15lbs of weight around the kart. Tire pressure in my opinion is the single most important thing in racing
@@kasonblake3655 It is definitely a great tool for adjusting these karts. And yeah, 1/2 lb can be noticeable for sure.
For scaling I was taught to set the air at 5 on the left 6 on the right….on a track with a lot of bite(like clay) that is a good baseline to start for air pressure…
On a slick dusty dirt track, 4 on left and 5 on the right is a good place to start with air……use .5# increments for adjustment after feeling the kart..
Lowering the air pressure will tighten the kart up, adding air pressure will loosen it…remember throughout the night, the track typically gets more bite on it from all the prep, ext..
@@TheKhager02 Yeah I think that's a good baseline and a pretty common one. I think we had a 2lb split on baseline for awhile too. 4-6lb. But I think consistency when it comes to a baseline is key. The car/kart will usually tell you what it needs eventually.
Would you be wanting to sell race ready if you still have it ?
I would if I still had it. I sold all my karting stuff in 2020. I'm trying to focus on the modifieds right now. My teammates have some outlaw wing karts they are still racing. There might be one or two of them going for sale sometime soon.
What chasis is that?
That's one of my teammates old chassis. Let me ask him. But that's a good question.
Thats an Ultramax. Errbody is winning on Chargers though. Biggest indoor race was last week and Charger Prodigy Cadet won 90% of the big shows on both days.
My kart is terrible pushing getting in and in center and it's making me loose on exit
Yeah that's usually the case with a chassis that's tight in and through the center.That's why you usually want to fix entry first. The main thing is to start getting more weight to the LS and just try to get weight off that RR. There are some other things that can help to like cross and tire pressure.
@@racerguy9483 How do you move weight from the rs to the ls in these karts. I know one way is physically move it.
@@miketimms7952 Yes, to physically move ballast is the easiest way. I would have several different size pucks to mount in different spots. Then I would move my seat if I needed more if possible. You can also use wheel spacing to adjust weight. Moving that RR in or out will make a noticeable change on the kart, especially on entry.
@@racerguy9483 The seat on these flat karts need to be easier to adjust cause the driver in the seat is the single most heaviest weight on the kart and needs to be able to slide front to back and side to side and on a pivot for rear seat height. Does moving the RF in and out affect corner entry?
What about the LF? I believe the Lf is under utilized in set-up as well, what are your thoughts?
@@miketimms7952 Yeah, a lot of them do have a sliding bracket. If you are already over or at race weight and running Predator/Clone class you will probably have to move the seat more to get the kart to balance. Those small motors can't handle too much excess weight.
First comment
In racing it's good to be first hahaha!
Thanks! Btw did you finally get that outlaw kart on the track?
@@racerguy9483 the engine is finally getting shipped this Wednesday I’m pretty sure
@@landenadamsracing88 Awesome! I look forward to seeing that kart on the track.
You gave zero numbers. on the rear axle you can only adjust mine about a 1/4 with out changing those slot cube thingys. Just wondering how much you move it and how much tire pressure are you running? You said take a little out of right front helps you how much is a little.05lbs-2.0lbs just curious trying to get all the knowledge I can. why is it such a big secrete
So the axles aren't adjustable on every make of kart. But some have marks on the cassette and that's where I usually adjust mine. But always start where the chassis builder recommends then adjust from there. Just go 1/4-1/2 inch increments. if you are ever in doubt just go less. You never want to over adjust and dial yourself right out of the race.You can usually get where you need to be by just moving the right rear in. But I would get everything I could with that RR spacing before I would start moving my axle. Tire Pressures 4lb LS and 6 lbs RS is where I think I used to start mine at on those flat/speedway style karts. And yes I would adjust in 1/2 lb increments. And nobody wants to give away what they think is their edge or knowledge they have accumulated over time. So that's why all the secrets hahaha. But there's no real secrets to any of this stuff. I hope that helps!
your talking but your not really saying anything
I commend your efforts here but you are just wrong about sooooo much.
Thanks! But the Title is How I Tune My Kart. That's it, just what I do with my stuff and a few of my opinions. I've been in racing long enough to know there's another thousand opinions on everything. Good thing is you can choose a multitude of different options and go run it and see what works for you. One thing I have figured out over the last 29 years since I started racing is that you can be right today, and completely out of the loop tomorrow. You never figure it out and it's always changing. Good luck on your races!