Anyone here have experience using tire warmers? Our club uses WKA rules and have confirmed that there is no rule not allowing them. We do a GWC qualifying and about half our time our outlap is not even half a lap to get temp in tires. Anyone with experience know how long after taking blankets off in normal 60 degree morning weather, if the remaining heat would still be effective.
I could have them on plugged in at pits, keep on then remove at grid but could be sitting for 5-10 min before released.
Never had any personal experience with them but I can’t imagine they would be all that useful. In my eyes, because not that many people use them is becomes another unnecessary thing to worry about at the track. If everyone had them then not using them would be a huge disadvantage but as far as I know they are not that common. Unless it is really cold it should only take 2-3 laps for the tires to come up to temp.
Would be interesting to hear from someone who has used them though.
Agree, 2-3 laps but like I said in post that’s not possible for qualifying. I realize everyone is in the same boat also. Might be worth testing if I can get them cheap enough.
Do a lap pushing on cold tires then compare a time warmed but maybe sitting 5 min unwrapped. Could also use a temp laser to see temp fall off after unwrapped.
Ya I would be very interested in seeing what the actual results look like.
My other worry would be the tires simply cooling off when the kart is sitting on the grid. I’m no scientist but if you watch F1 they take the blankets off at the last minute possible and so my guess is that if it is actually cold enough to need tire blankets, they won’t make much difference if the kart sits for 5 or 10 minutes with them off on the grid.
My first reaction was the word “illegal” - apparently they are not at your track - but I could swear I’ve seen the on a rule set before.
Past any performance advantage they would be beneficial if they minimized heat cycles, thereby giving better tire life.
They work exactly as planned - good grip right out of the pits - but by the third lap there’s no difference. Unfortunately, they only start timing qualifying laps on the third lap, so the obvious advantage of going out before everyone else is ready and setting a screaming lap time on the first try isn’t going to work.
The main benefit to tire towels (yeah, towels - a buck at Meijer) is that they cut down on the number of heat cycles in a weekend.
What do you mean they start timing qualifying laps on the third lap? Every race I’ve run has either been a 3 lap session or a 5 minute session. Both start scoring the first flying lap, never have they waited laps to do official scoring.
We actually tested them this year in cold weather for the KA Throwdown and they made a massive difference on the first two laps. Where other guys were struggling to get tires up to temp in 35-40 degree weather, I was basically at optimum grip out of the pits.
In cold weather, I think they can be valuable if they are legal. In warmer weather, the advantage would be minimal.
Interesting, I had a similar observation with tire softener. Back when I first bought my Kosmic prepping tires was legal and the tires that came on it were prepped. Since our first races are typically run with snow still on the ground, I noticed the tires were immediately able to stick to the track while the others struggled for grip for a couple laps. It didn’t matter once it was warm outside, but in the cold the tire prep really helped. That’s probably not legal for this scenario though.
In 60° weather, tire warmers may help slightly but I don’t know how much.
Thank you Tj, exactly the info I wanted. Now how long were they off to on the track?
Not talking smack but if my original post was read I wasn’t concerned with 2 or 3 laps later. It’s the initial lap I’m trying to get an edge on. They are legal in my organization and no we aren’t savages. Like I also stated we run a Green-white-checkered qualifying. Have to be quick right out of the gate.
We were allowed to run tire warmers in the car series we ran this past season. They did make a big difference compared to no warmers. But you have to wait until the last possible second to remove them to get true peak performance. We would wait until 1 minute before cars rolled off grid to take them out and put them on the car. Otherwise you’re losing that optimal temp and pressure sitting on grid. Also, keep in mind that you want to heat the whole wheel and tire package, not just the surface of the tire. You want that core temperature. So they will have to sit in the warmers for a while before each session. We put the tires in the oven an hour before each session to bring them up to temp. Granted, ours are a lot more material to heat, but you’ll still need to have kart tires in the warmers ~20-30min before each session. Which isn’t feasible for a normal practice day. But could be possible during a race day.
Agree 100% with Zach. You need the tires to sit in the blankets for a while to get core temp up, then they should hold heat a bit better when you need to take them off and get to the grid.
Between taking the warmers off and going on track was probably 7-10 minutes with air temperature about 40 degrees outside.
I’m guessing you check the tire pressures at the last minute as well?
We did, but one thing to note is that at 40-ish degrees, it was cold enough that the tires actually lost pressure throughout the run and by the time they had cooled down, they were far lower than we normally would set them cold at.
We usually run around 10-11 psi on MG Reds, and so we had these heated, we set them a little higher thinking we wanted to try and replicate what their pressure was at max temp normally. When we get off the track, they had dropped to 9 or so and when they had fully cooled down in the pits they were at 7-8 psi, which is much lower than our normal cold pressure. So you just need to try and account for that pressure variance when you’re setting pressures. With the warmers on, you want to set your pressures somewhere around where they normally are hot, not where you set them cold. Seems obvious looking back, but at the time it didn’t really dawn on us.
Edit: To James,
That would be the easiest way. Set them hot, record the pressure and ambient/track temp, and then let them cool. Then you have your cold pressure for that ambient/track temp. I don’t do the pressures on our cars, but I’m 99% sure his formula is raise cold pressure by 0.7psi for every 5* colder of track temp. Keep in mind, that’s for cars that have a lot more air volume than karts do. So your ratio will probably be different.
Yeah typically I look for no more than 2psi increase over the session.
Historically tire warmers have been not allowed in karting. I’d be afraid to make the investment and then have them added to the rules as being not allowed in the future. Of course it should be OK on practice days.
WKA does not have a rule banning them. Emailed the organizers of my club and confirmed they are allowed. We use WKA rules.
I’m surprised because I’m pretty sure when we used to run Manufacturer’s Cup, they checked the tire temps on the way to the grid and made it clear tires had to be ambient temperature.
Sounds like you’ve thoroughly checked this though, and maybe found a good little advantage in the rulebook, as a true racer does.
Hmmmmm, when you stumble upon a post about tire warmers and see that the OP is a guy you race against… I see you Bryan Williams!..lol