Yes I would. Like I said, I always run my seat this height in the past.
My conclusion is based off the fact that the kart is working best with both ride heights up. That says to me that the center of gravity needs to be raised as a baseline. So up goes the seat.
Raising the seat will give you more weight transfer.
Bit of a trying day today. We hovered about 0.8 off the best times and are struggling with the balance of the kart a bit.
It feels kind of like the frame is flexing and rebounding so we are going to be trying to stiffen it up a few different ways tomorrow.
Itâs crazy how much grip there is compared to last time I raced here. When I won the 2018 USPKS races here, I ran 50.9, 51.0. With the new tire and the extra rubber on the track, lap times are a second and a half faster. I had to spend some time adapting to later braking points, faster apex speeds, and more G-loads.
Thatâs pretty insane.
You are on the reds, right? I hate those tiresâŚ
Yes, and I love them. On a 206 I can imagine it would be tough though. Even on the KA we are trying to take grip out of the kart and keep it from over flexing.
With the amount of grip that these tyre look to be putting out
Wouldnât it be better to be in the stiffer chassis
That is what we are thinking. The other drivers in our tent are on a slightly stiffer chassis and it seems more stable and more able to hold onto the grip and not over flex.
Got a stiffer chassis available? Going to go to the big boy set up and go HH on axle? Put seat back down? Take me through your thought process on next steps Please!
I heard from talking with a friend that Justin White has been doing what you are doing as well for Maranello (testing and development) and the chassis behaves very differently in US grip levels as compared to what works in Euro grip. Similar challenges iirc. In his case I think itâs the KZ chassis. Maybe he has some ideas that worked out.
Raising the CG makes the flex much worse though - have you tried lowering the seat back down?
The track got really gripped up with USPKS and hasnât had any real rain since. I scraped about 2lbs of rubber of my daughterâs tires this past Saturday, haha
I wish I had some next steps to share⌠scratching my head a bit at the moment.
For that session I put the plastic bar in the front, lowered front ride height, stiffened the axle, and went about the same speed and the kart felt similar.
It feels very inconsistent right now, but it feels like neither end of the kart is working.
Yeah I may do that. Itâs been on my mind to change that back since we know what it does when itâs lower.
Currently looking for cracks in the frame because it is behaving so unpredictably.
It is good we have some nice data to compare with as I have a teammate this weekend and some good testing data from last week.
The data shows I am 0.1 behind the leaders for the first half of the lap. Which would be a 49.3 and thatâd be front running pace. I am losing two tenths in every corner after that.
Iâm lowering the seat now. I think itâs just too reactive with the higher CoG. I hope youâre right Caleb!
Good luck! Itâs drizzled a couple times over here on the other side of Mooresville, so Murphy says youâll get it dialed in perfect right before it rains, haha
Well lowering the seat solved like 50% of our issues. Kart was miles more stable and comfortable and we gained about 0.2 on the field. More importantly I can actually feel the kart again and I feel like we are in the window to tune now. Before it was so reactive and unstable I couldnât tell what it was legitimately doing from apex to exit because every lap it would respond differently.
Need to strengthen the front a touch now and review data for gearing. I have a BestKart teammate this weekend in local shoe Byron Daley so it is great weâve got some good data to share session to session.
16th to 12th in that one and getting closer in times to the leaders. Kart gets better every session now. Picked up 4 more spots post race after penalties too which was a nice bonus.
Tried a different bar in the front that time because the kart felt a bit understeery after we moved that seat down. That helped really well in the tight corners. We were a bit high on pressure and started to cook the fronts a little by the end of that run. We ran a bit higher to try and make early progress.
We made the final! Finished P13 in that final heat. It was a battle though, had to defend quite a bit and cross-over quite a few times to hold onto positions.
For that one I turned a click of negative camber out to try and stand the tire up a bit more for more front end and to try and alleviate the front tires overheating. I donât think it didnât much; still burned up the fronts so I think itâs something Iâm doing driving-wise. I think I am too aggressive on entry to turn 4 and using the front tire to slow the kart down a bit.
Need to ponder on setup for tomorrow but a relief to have two clean heats and be into the final. P18 starting spot so a nice improvement from P32 in qualifying.
What axle are you running, and what ride heights are you at? The Bestkart isnt terribly different than a KR which Iâve been running this season.
In the KR we have no front bar, but we run full rake (rear high, front low) which stabilizes the whole thing pretty well. This season we had been on the medium axle, to our disbelief. The new compound is just very very different.
I also find that axle length makes a noticeable change for me in the KR. Cut to 1000 will have considerably more sidebite, and 1030 if you want it to smooth out.
I know youâre in Sr which is a different weight but I also run the seat pretty far forward. If you have time scale your kart if you havent already, you might be way off in some area and not realize!
Any time smaller adjustments (like the camber change) donât make a difference, that is a clue that something more fundamental is off. Reading through your reports, it sounds like the front end needs to be more responsive, such that tiny inputs get the outside rear driving the kart around the inside front sooner, instead of the fronts having to laterally push the front of the kart to maintain the arc. I would put the negative camber back in, moving the seat forward a small increment, and increase front track width. My 0.02
Front is medium and rear is high. With the front low, turn-in isnât great and it makes the front a bit dead. The baseline we run usually is front low and rear high.
Yep, short axle is on the list of possibilities today depending on track conditions. Currently running the C axle (stiff) but considering a cut B to free it up and get the outside tire to dig more. If I can help rear rotate without getting too free, I think the front wonât have to work so hard.
My seat is basically touching the gas tank already.
I like the negative because it helps the kart release off the corner better and reduces scrub through the fast corners, which is basically this whole track. So thatâs on the list today too. Also considering front track width as well.
We donât usually run the bar in the front but we have a different âspecialâ bar we are trying and I actually really like it compared to the standard plastic bar.
I know I can get the front working better; we have lots of adjustments we can still do. My only concern is making sure the rear can cope as well, because it has generally tended toward the free side all weekend. Fine line to balance.
What do you mean by âreboundingâ?