The kart was transferring so much weight with the seat higher, it felt like the frame was folding and releasing. Like when the rear hops, but the whole kart.
I was making a lot of inputs every corner because the kart was so on edge.
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P21 overall in warm-up, about 0.6 off. A step softer on the axle was better but I think we need to dump caster into this thing. Struggling with tire warm-up, I think because we are not working the rears enough with chassis flex. But then the front tires fade too quick, because I think the rear is just pushing the fronts when it comes in. My theory is that caster will help initiate that immediate wheel hike and thatâll put more load into the rear tire and help warm up the tires, and itâll get the front to hold the wheel up longer and make it more front-end positive in the spots I need it.
Also comparing some data before the session gave me a few driving things to work on. My style has always been hard on front tires because my hands are pretty slow on initial input so I tend to use the front tires a bit more for slowing the kart down. I feel like I fixed that a bit in warm-up; initiating a more aggressive turn-in to help it rotate sooner and use more brake and less front tire for deceleration. But I need the kart to react a bit quicker now to fully dial that in. Currently I have to have wheel in it too far into the corner which also burns the tires up.
So changes for next session are looking like:
- more caster
- possibly a cut axle depending on how my teammate feels the track is in his pre-final-
Long break now before the pre.
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I like the reasoning for more caster. Sounds like youâre on a good path. If you can get it turned sooner and quicker and not âgrindâ on the front end through the middle and exit, you are going to be faster and easier on the tires.
Caster was not faster. It was a disaster. I havenât driven a kart that was that overstuck in a loooong time. Just absolutely glued down in the tight stuff and flat sliding like a sprint car on a slicked off Knoxville in the fast corners. Absolutely evil to drive and just felt pretty helpless to defend. Fell back to 23rd at the end.
The worst part was the caster didnât even really feel like it helped the front end that much.
Glad we have a few hours before the final to think on this.
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To me it sounds the fronts are burning up because they cant follow the right path for each tyre. Too little ackerman. The chassis will bound upwards on entry. Ad more ackerman like 10mm to each side and you will notice it will not bend the chassis anymore. Adding ackerman also compares to adding caster as the inside front turns more. Adding ackerman 2mm or so per side does nothing. Make big steps
I would take all the caster out. Modern chassis like crg and tonykart have 20 degrees of caster- Thats way too much inbuilt caster (mechanical lift ) for a fast driver. If the driver is slow as a dog and doesnt carry much corner speed - then he will need all the caster in the world
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I also somehow got a penalty for avoidable contact in that one even though I was the one who got run off the track in turn 8 and I was never behind anyone to contact them because I was getting passed. They wonât tell me who it was with and they wonât review my video so that isnât fun. Doesnât matter much in the grand scheme of things but it is a little salt in the wound.
Totally agree with this. Max Ackermann and take the caster out. Cut axle too if you havenât already!
I didnât want caster in but I was running out of front end options.
So that was a very frustrating end. We theorized that maybe the soft chassis was too soft for this grip level and maybe there was something fundamentally wrong, so we made the wild call to swap frames before the final since we had four hours. We did this because we wanted to try the same medium soft my teammate was on which seemed to be working better. And we wanted a true apples to apples comparison so we set it up exactly the same as my teammate. And to rule out any issues with the frame.
I lined up 24th for the final and it was pretty rough. I just had no release off the corner, no confidence in the fast stuff, no pace at all. Felt very similar to the other kart. I very rarely have been so frustrated in a kart. I think we ended P28. Meanwhile my teammate Daley drove great to come from the back to P18 and was a few tenths quicker than me. His tires looked good, he said his kart felt good. I tried everything I could in the seat but just couldnât get anything to work.
With that, there are two possibilities:
- we had a bad set of tires or we torched them so bad they were just done
- Iâm just not as good of a driver anymore or I was missing something in my driving this weekend
Given that the kart was decent in warm-up, Iâm leaning toward the latter. I was just very lost on everything this weekend I felt like I was driving well but the numbers donât lie in the end. Lots of negative emotions right now so maybe Iâm being hard on myself but Iâm sort of out of answers this weekend.
The team was great, and Daley raced well and was only 0.2 off the leaders in the final which was great given is relative lack of experience at this level.
The team is going to do some testing soon to double-check everything and see if something was truly up with tires or see if they can learn anything.
So with that the Stars season is over and Badger will be closing for the season in a few weeks and that means I am pretty well done for the year in terms of testing. Iâm not sure what will be happening the future with BestKart or further AMV collaborations but for now I think I need to consider if I am at a proper level to race these national events or if itâs time to step away for a while and hang up the helmet. Wisconsin winter is long so I have time to think and lick my wounds a bit.
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Well one way to look at it is this. The name of the thread youâve started has development in it.
While begin up front this weekend is the short term goal, the long term goal is learning what does and doesnât work. You kinda signed up as a guinea pig. You now know that the frame/tire/setup combo doesnât work.
Time for a stiffer frame for the next one.
Iâll be honest and say that the âIâm just not as good of a driver anymoreâ statement is completely false.
- Does Daley have the same build as you? Same height, etc? I know you played around with moving the seat up and down, but thatâs still not the same as a different build driver.
- Especially if you had a session where the kart was just super âstuckâ, you DEFINITELY could have cooked the tires to the point they were done. I feel like thereâs been a lot of positivity around the MG SH but in my experience they are about a second slower after a race weekend, and thats treating them really well.
- Youâve run up front recently when you still had your Exprit chassis, and that was very used. Iâm confident in saying that there is something fundamentally wrong with the chassis right now. Iâm not sure if Montopoli was on the same frame as you, but it looked like he struggled throughout the weekend too and heâs usually pretty quick. Sure, maybe Daley got something out of it, but it could just a number of things that arent the chassis. What motor does he have? How many hours on it? Like mentioned before, is he the same build, does he need to add as much weight to the kart as you do? Maybe he had an uncharacteristically good set of tires. Thereâs a whole host of things.
- Mentioned in 3 but the motor is extremely important in KA, and especially at that track. If yours wasnât on it or basically tuned for it (I know BBS basically tunes for higher RPM) then youâll be getting dusted.
I think part of the issue with the development process right now is that you donât really have a âcontrolâ to go on. It would be interesting to see what you do in a Kart Republic, since it seems like thatâs the closest design. There must be something that is fundamentally different in the wrong way, and without having a known developed starting point itâs difficult to know whatâs what. Sure, the chassis can feel balanced, but balanced =/= automatically fast. A few ideas come to mind that could be different and causing you some trouble:
- Maybe the spindle design/stiffness
- It does really seem like the ackermann is not quite right. A lot of your comments were âits not releasingâ or âdoesnt have front endâ and the caster changes just made that more confusing - something isnât right there.
- Floorpan stiffness. It just seems like the whole mid-front section of the kart isnt behaving right.
- Is it a soft seat?
Like youâve said, youâve won USPKS at this same track. You have a ton of karting knowledge that is sure to make you very quick. As âeasyâ as it is to blame the kart, Iâm pretty confident thereâs something wrong, and itâs not you.
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I really appreciate the kind words David. Now that some of the emotion is out of it, maybe I was a bit hard on myself but I do have to look at it analytically and drill down into the variables at play. I also need to deep dive into the data this week and see if I can find anything that stands out. But I always want to make sure to blame equipment LAST, so first and foremost I need to look and see if there is anything that stands out as a driving issue, because the reality is that Byronâs kart was identical to mine in setup and gearing and everything and not only did he go faster, his tires looked significantly better than mine.
Iâm not sure when the team will be able to test again but one thing we wanted to do is put someone in my kart on my tires and back-to-back the tires from the two karts. The ONLY variables between the karts were:
- engine
- driver
- tires
- Byron is similar build to me, so itâs not like a massive difference in seat position or CoG.
- The tires could be a factor. I have not seen crazy drop-off on this tire and everyone was in the same boat on how many sessions were on the tires and no one else seemed to have this issue. My only thought would be, did we completely overheat them to the point where they were compromised?
- I donât remember what engine Daley was on, but I have confidence in the engine. In the data, if anything, MY engine was stronger. The acceleration traces show that I had more mid-top power. And my engine didnât have that many hours on it.
- My engine shouldâve been well-suited to this track based on itâs power curve. Plus, as I noted, I was pretty decent in warm-up on Sunday even, so that makes me more confused. I was 0.2 off Jones and McMurray, which is obviously THE benchmark at that track. Those guys won the heats. Being 0.2 of them was a good start to the day when I felt like the kart still wasnât perfect. I really thought we had something on our hands after that session.
Yes, the hardest part is that there is no âbaselineâ for this kart yet. Thatâs what we have been developing, so itâs been hard to know sometimes if we are even in the window. The only thing I can thing of as potentially being a misstep, was maybe I shouldnât have trended toward Daleyâs setup as much, and shouldâve tried to find my own way a bit more. Itâs possible Daleyâs driving style was different enough that what worked for him wasnât working for me. Prodigy tested a lot here and itâs their home track, so the setup and tuning theory we ran was pretty different to what I had normally been running. But my setup wasnât perfect, so maybe I tried too hard to lean on Byronâs setup knowing he was making it work pretty good. But what works for him mightâve not necessarily worked for me and maybe I shouldâve stopped going that direction earlier.
The other mistake I made was raising the seat before the weekend. That was a huge miscalculation from me because I basically lost most of my practice day chasing setup with the seat higher, and then finally once I realized that was the issue, I didnât have a lot of sessions to test many more things before we got into official sessions.
Regarding your points on the chassis itself:
- I donât think this is the issue. We pretty much settled on the stiff stub ends as being the way forward and the spindle itself is pretty stiff which I think is the right way forward based on previous testing.
- I wish I had more time to test this one out too. I havenât played much with Ackermann changes and would like to get a feel for that.
- We run aluminum pans but I have thought about softer/stiffer pans.
- Standard Tillett T11 per factory recommendation. A softer seat mightâve helped it in the tight corner but the kart was already pretty unstable in the fast stuff and I would be concerned it would get worse with something that flexed more.
I appreciate all the insights and suggestions on adjustments people have offered. I spend basically every minute of the weekend, on-track and off-track, trying to decipher and analyze what the kart is doing, how to fix it, and which adjustments to make. There are a lot of good things you guys have mentioned that I thought about too (I thought about everythingâŠ), I just obviously have limited time so I canât test everything in a weekend so sometimes I need to go with the adjustments I am most familiar with to find a direction to tune, and then I can start trying other things like Ackermann or seat or whatever once I understand where the kart needs to go. The frustrating part about this weekend is that I spent a LOT of time confused on the kart and I just could not figure out which direction to go.
The comments here and the plane ride gave me a lot to reflect on, so I have some ideas floating around that I will pass onto Chris at Prodigy and Tommaso at BestKart to see if they want to try some things. As noted, I donât think Iâll really get to test anymore this season as winter closes in, but still would like to help develop the kart if I can.
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In a pinch, we just bolted on two pans together to âdoubleâ the stiffness. Worked wonders when other traditional changes were not working or going too far.
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I think Paul actually had the floor pan tight at one point. I did test that a couple months back and didnât like it then maybe it wouldâve worked better with this grip level.
Tried the same. The two pans helped with over-flexing the chassis, when the tightly bolted single was not a noticeable change for me. I was having a hard time under braking and initial turn-in. Felt like the frame was folding up underneath me and the rear inside tire was gonna whack me on the back of the helmet.
The karts work differently for sure, but my issue felt like the front was giving up again. Not much rear lift at all. But the CompKart works more like an OTK and the BestKart more like a KR. So different philosophies but maybe similar issues in this regard.
I also considered that the BestKart driving style might not be as suited to my driving style when the grip levels and track layout were as they were this weekend but then my ego jumped in and told me I should be able to adapt to any driving style at this point in my career⊠or am I too old to learn new tricks!?
Roger that. It was while running OTK, but the point applies regardless. To me, it was like bumping up the whole frame from 30mm to a 32mm. Thought you said the frame felt soft overall somewhere in the thread.
Meh I think we are the same age⊠unless the physicality becomes too much I donât see why you can keep moving forward. I just remind myself that Alonso is in his 40s. 
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Well, Iâm glad youâre feeling better after some time to reflect. Racing can be very humbling and I know the general feeling quite well 
Developing a chassis for the American market is no small feat!
To respond to you though, it generally seems like an ackermann issue. Iâd be happy to help run some calculations for you/the Bestkart guys if you need a hand there!
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âNoâ
~ Fernando Alonso
âAlso no, but in Italian.â
~Davide Fore
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This has gotten me in trouble several times. Chasing someone elseâs setup just going the wrong way. I have my own way of driving and tuning for better or worse so I just have to trust my own intuition.
So are you running like a KR and no torsion bar?
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