Never seen that.

 

Its a good point. If you ever watch the thermal cameras on F1 the tires cool off before they are out of pit lane. However, that is surface temperature and I have to think that if the whole tire and wheel are warmed up it gives you an edge to get them back to optimum temperature rather than starting from cold.

I really am considering buying these if only to use them at the beginning of the day in early spring or late fall when the morning temperatures can be 40 degrees. Every bit helps, right?

 

Well, I have thought about it and I know why I don't use them. It has to do with how the NASA gridding procedure works. We go from our pits to the pre-grid and sit there for at least 5 minutes. Then we go out for a slow recon lap and the race starts.

By the time the race starts, the tires would have cooled off dramatically compared to what they were when the tire warmers came off.

To make the tire warmers fully effective, they would have to be put back on when I got to the pre-grid. The recon lap would need to be run at near race pace too.

 

good question about if keeping them warm..(cooking them for a weekend) vs the heat cycling is better for their life, and stickiness.

 

Not sure why it would not be allowed?

 

Heard back from Jeff S. at Hoosier. He stated that using the warmers between runs will not increase the life of the tire at all. They are great for getting them up to temperature, so you can go out faster, but that's it. He also said that heating the tire up and letting it cool with warmers is not that same as a heat cycle on track.

 

Has anyone bought these ebay cheapies? They're a lot cheaper than 2nd hand chickenhawk's, but are they junk?

I would use them for hillclimbing and time attack...

 

That is not completely accurate. What you need to warm (and don't try touching it with your bare hands when entering the pit lane) is your rims. Once these are up to temperature they will hold their heat quite a long time. Of course top surface temps will suffer when standing still and you won't be able to go flat-out in corner one of the race, but the time to get the surface temperature ok will be greatly reduced when there is enough warmth in the rims, compared to starting with ice cold wheels.

I guess a few of us (myself included) have driven to/from the track and on the track with the same set of tires. (Sorry for the metric system, please convert when necessary). If my tires at the end of the last session are 2.2 bar hot on the rear and I start driving home they will be around 1.5 or sth like that after one hour of street driving on the highway. Even if I inflate them to 3 bar before leaving the track they get tot 1.8-ish after a while, but this doesn't happen over the course of 10 minutes. It takes a while. If I drive my tires cold on the same highway the pressure increases by about 0.2 bar, so there is not a huge amount of heat generated by simply driving on the street in a straight line at the same speed. It takes soo long to drop pressure because the rims need quite some time to cool down.

 

It is a fair point. Tires heat up mostly from the heat of the brakes warming the wheels and then into the tires. If you warm everything together might the tire come up to temperature a lap or two quicker?

 

Really???

 

I am not sure about the "mostly" but if will for sure contribute considering the amount of heat these things generate.

 

Get a copy. This is the current bible.

 

^^This^^

Been the bible for more than a decade...

LuigiVampa, the rim warming from the brakes is a byproduct, not the preferred or even possible warming method. While it is an issue particularly from heat soak after hard use, ON THE OUT LAP AND PACE LAP, it takes a long(er) time to do this and certainly is not a factor in those (slow) out laps and pace lap for tire pressure normalizing.

The rotors and hubs have to absorb the heat from aggressive braking first (and the most heat comes from braking from vMax to a slow corner at least three or four times, close enough together so it doesn't dissipate too much), then the heat has to permeate through the center mass and mounting of the wheel, only then does the air inside the tire begins to have any effect on pressures.

Again, the most effective, proven and data supported way of warming the tires to close to operating temperature normalization required is aggressive acceleration and braking, coupled with as extended a cornering stress as you can put on the tires in the out lap and on the pace lap, such that the diagonally wrapped bands of the tire's carcass rub together and create friction that permeates not only inward, but through the foundation of the tread layer, ensuring equalized and sustainable growth.

 

At some point, I may wish you cease repeating this.

Understanding and trusting this becomes an "Unfair Advantage".

 

Buying this books is the easy part. Now all I have to buy is time to read it. Have another data logging bible at home for which I just don't find the time to read. (This stuff does take some focussing, not exactly bedtime material )