MG told me once that the best way to warm up the tires is big, sweeping movements all the way from one side of the track to the other.
Since our caliper is on the axle, braking has no effect on warming the tires correct? I always warm up my brakes, regardless.[/quote]
Not from the heat of the brake, too far away from the wheel.
Heat from working the sidewall might. No front brakes on most karts means no effect on fronts at all or a little from weight transfer. It is just more effective in a car vs a kart due to 4 wheel brake vs 1 axle brake. Even in a car you have to consider where the brake is. If it is inboard, it’s more like a kart.
In a car you usually have more room on tracks, It is pretty tight on a sprint kart track. Then there is mirrors vs no mirrors.
I have seen more than one driver have a single kart accident before the green.
At a night race my brother got taken out before the green. The guy behind him (in his own words) stared up at the lights to see what it would do, blinded himself and knocked my brother off track. Fairly brilliant, but what you gonna do?
It’s kinda pointless to measure the temps of different styles of warming up tires without measuring the grip levels or lap times for each test. Also, grip and tire temp are not linear. So maybe you only increase the temp by 20 degrees… but if you find 30% more traction. Boom.
Tire warmers do work on karts for sure… however for the most part they are banned.
Remember you also have two things you are trying to warm up. The tire tread/surface and also the air/nitrogen inside the tire to the optimum inflation pressure so that your contact patch and spring rate are on point… or as close as you can get them.
Weaving violently doesn’t have to be dangerous if the drivers give each other enough room. Problem is… a lot of the time, drivers didn’t… so it was banned.
For me, smoking the tires in the outlap was 40% warming up the tires the tires and 60% warming up mentally, getting psyched up to kill it on the start and opening lap. I ended up being pretty decent at that. After the first lap… yeah not so much
Nowadays I try to work them really hard in the turns… long periods of time at smaller angles. Also alternating between the fronts and rears to try and keep some balance. You can work the front by overspeeding into the turn and give it a healthy dose of wheel input. Just be ready for it to shift the rear out depending on your setup.
I can’t imagine brakes having much of a significant effect on tire temps in anything but extreme circumstances.
I think making short extreme movements do warm up the tyres but also contributes to tyre wear with grippy tyres. Does that make sense?
Yeah that makes sense. I think when you make short extreme movements, you’re doing more heating of the surface of the tire. Longer, sweeping movements probably brings the tire up to temp quicker and helps heat the inside of the tire as well.
If only we had an F1 tire engineer on-hand, I’m sure he could explain it all to us!
I don’t know an F1 tire engineer, but I do know an ex-F1 engineer. I’ll ask him after my lecture on Thursday about this and see if he knows anything.
In F1 the way to heat tires is accelerate & brake.
But then weaving is used too. You have to do what you can in the condition you have ATM.
Here is a question: “Does it matter more if you are at the front of the grid or rear?”
F1 has brakes on all four though. Most kart are rear only except shifters and superkarts.
Also the amount of heat put through F1 brake rotors is ridiculous, so that really helps warm up tires.
Just because F1 does it, doesnt mean it applies…
Kart brakes are inboard, not inside the wheel so there is no effective heat transfer like with basically any other wheeled motorsports. Scrub the tires to get crap off them, and drive a clean line. A partial lap at speed doesn’t seem enough to put much heat into them, but it helps.