Sigh. This will take us into the weeds about what annoyed me with this transaction. The kart was received late, presumably ran as a rental in a race series somewhere. I am pretty sure they just handed it to me, assuming it was fine. I did not develop a productive relationship with the last guy. I think he probably did not understand the depth to which I felt the kart had problems and I wasn’t able to articulate it effectively.
That’s why Saturday, I decided to just do something, and asked the other fella to move the seat forwards a couple cm. He listened to my issue and made a couple other suggestions. Progress was made.
I will absolutely suck in this series, but maybe I should consider this a part of my education, a sort of intro to kart tuning IRL.
Are we sure the braking instabilities are not from the rock hard tires? I dont think any amount of bar tuning or front end tuning is going to change that. Are your rear hubs tight? Have you tried balancing all 4 wheels?
The point in can be helped with more weight transfer, I believe. Do you have the caster in? Do you have the next offset pills (red ones, I believe?). My Ignite liked caster out, but pretty wide front end and bar max stiffness. Again, I’m jsut some rando from the internet telling you how to tune from the comfort of my couch, but it might be worth a test session to try.
Like many others have said, its pushing on a lot. But as you don’t know the history, I would return to the base setup and it still turns in like that then I’d move the track rods end inwards on the stub axles to give you more ackerman, as illustrated below with my little red arrow.
I’m not really seeing the knife edge hoppiness you describe, but it might feel that way if the rear is really stiff (bouncing off every imperfection in the asphalt instead of absorbing it).
It is my understanding that a kart ALWAYS needs a little toe OUT-- toe IN makes it quite darty. The problem is: how much toe out is needed on the stand to get maybe 1/2 mm out per side on the ground with driver? Following a test used by Nick Firestone, I set my toe out to 2 1/2 mm per side on the stand, put it on the ground and sat on the back of the seat so I could read the sniper. It went from 2 1/2 mm toe out on the stand to 1/2 mm toe out on the ground with driver. My kart is a CRG KT 2 (30/30 frame that tests faster with no front torsion bar, even with 3 1/2 spacers out per side).
No doubt that is a lot of wheel input to get the thing to turn. If the rear is too planted and not lifting the inside rear, then the steering is going to be shit. By cranking the wheel that much, you are forcing more caster input effectively driving the inside front tire further into the ground. You could try adding caster (leaning the kingpin further back) to improve the jacking effect. As far as twitchy steering under straight line braking, its hard to say with out feeling it. Does it feel like the kart is changing direction and you are compensating with steering input or does it feel like the steering wheel is fighting you and you are trying to hold it straight?
If the kart is changing direction with no steering input, it could be the rear getting light and floating around (move weight back). If the steering is fighting you, then it could be a front end alignment that is caused by the tires fighting for direction (too much toe in/toe out).
same subject, kind of, but i have the solid tube front torsion bar, and i have two of them. right now, my options are it’s either in, or it’s out. since i have two bars, i was considering drilling some holes in one, or some slots, thinking it may give it some flexibility. anyone ever try this? my concerns are that the modified torsion bar will just bend, instead of flex, but since i have two of them, i might as well give it a try. i’m pretty sure there are some engineer dudes in here, please let me know what you think. thanks!
Hey David, nope I sort of gave up. I am in contact with a team owner locally who is open to going over the kart, getting it to his baseline and going from there.
I hope I can get this done for the upcoming season and maybe race lo for real. As it stands my experience with the kart purchase and subsequent dealings with the folks who sold it to me were baffling.
Really bad taste and I kind of turned my back on it in disappointment and frustration. A waste of my time and money.
I’m also kind of annoyed at the owner of the whole shebang for not asking the question, “why is the dude who was gonna race with us not racing with us?”
I don’t think torsion bar either. I was just trying to chase down the “maybe it’s me” angles.
Both. This is because I plopped all the weight forwards and introduced instability. I can feel it and understand it. Think frontal hop with dartiness. I masked a problem with a kluxge solution to get a second out of the chassis in desperation so as not to be lapped. But it’s not workable. As TJ said, the front end is utterly unresponsive and effectively broken.
I just kinda of wanted to set it on fire and move on. Hopefully McAleer is able to check it out and settle this. I think it’s farked on some deep level but my lack of wrenching exp makes the whole thing so frustrating. Having to depend on others is not great and pisses me off on a personal level. Bit, if Steve is willing, I’d be grateful and willing to revisit this bit of my karting experience I’d rather forget.
That does sound very frustrating! It sounds like getting a team owner to look over the kart is a great first step. Finding a shop you can trust with frame straightening, looking over the kart for issues like these, or motor rebuilds is important. Once race season gets started again, dont be afraid to ask people around the track for advice/help and definitely dont be embarrassed about wrenching skills. Everybody has to start somewhere and I find that the karting community is very supportive.
