Keep thy rubbers warm.

[Raptor]

KEEP THY RUBBERS WARM

Article is extracted from Supermoto Racer Magazine

 

Again manually typed by me till fingers hurt. But then what is a bit of numb fingers if my racing buddies can learn something from this.

 

 

It doesn’t matter if you’re a slow-mo-Joe or a hot-shoe-go-faster, warm tires are your friend. If you think one warm-up lap at half speed is enough to heat up them black donuts, you really need to put down the modeling glue. It even took SMR (Supermoto Racer Magazine) a year of racing to realize the guys with tire warmers weren’t just trying to look all pro. They knew something we didn’t. The first time we toasted our meats before a race, it was an eye opening experience – consistent grip from the first turn to the checkered flag. Believe it or not, when you run cold tires during a 5 or 7 lap qualifier, its not enough time to bring them up to full operating temperature.

 

We hooked up with Chicken Hawk Racing Tire Warmers’ guru, David Podolsky, for some insight on tire warmers and why every supermoto racer should have a set and know how to use them. No, the story isn’t littered with SMR puns and witless banter but this is a must read story for any racer with tons of useful information. Here is what David has to say:

 

Chicken Hawk receives dozens of calls each week to talk about tire warmers, but that’s not what the callers really want to talk about. They want to understand how tire warmers can influence their race tires and why do they need them.

 

Horsepower is a wonderful thing but if you can’t put it to the ground, its useless. This is why I think that most supermoto riders are after the optimal setup and tire performance over a few extra ponies at the rear wheel. Set up and grip allow the motorcycle to be ridden with confidence and remain stable throughout the turn with a good drive down the next straight. This makes for fast laps and happy racers.

 

Some riders get caught up in simply getting more power as a solution to winning. Others focus on the myriad options available such as rake, trail and suspension settings. Riders and teams tend to focus on these hard numbers and feel that the tires are what they are. When it comes to working with tires, there are usually a few compound choices available from the supplier suitable for the track and conditions, along with selecting a tire pressure. Don’t despair, there may be a few things you can do to influence your tire’s performance.

 

One way to ‘manage’ tires and get better use of your available track time is to utilize tire warmers to their full ability. The following will be a review of the ways to work with tire warmers in assisting your racing efforts.

 

 

 

GOING QUICK FROM THE OUT LAP

A tire warmer’s first and most obvious use is getting the tire up to operating temperature prior to heading onto the track. Even on hot days, tires are far below the temperature required for optimum grip and it will take some circulating on the track to get the tires into operating range. Most race tires work best at carcass temperatures between 75 – 100 C. depending on the compound. Most supermoto tires run on the low side of the scale. Certainly, when the weather is less than balmy and track surfaces are cold, the amount of time to get the tire ‘up to temperature’ can take additional laps.

 

Sometimes riders think of this function as the only benefit a tire warmer affords, but there are more subtle and equally important gains to be had.

 

HOT PRESSURE

All the top tire manufacturers are concerned with their product being used with the proper hot tire pressure on the track. As the tire heats up to operating temperatures, the pressure of the tire increases as well. This increase can be from 15%-35% of cold settings, which is quite significant in the performance and handling. The tire is the first ‘damper’ or suspension component to begin working, as it is in contact with the track surface. A tire at its proper hot pressure will work the suspension properly. It will be stiffer as the cords and belts are now under more tension. When the tire is loaded, this results in additional grip. We all know how swishy and under inflated tire feels. For the tire to perform as desired during braking, cornering and acceleration, having the hot pressure correct is essential.

 

Utilizing tire warmers in the pits is one way to assist in this setup. A properly designed tire warmer not only heats up the surface of the tire, but ‘heat soaks’ the entire carcass. This results in a stable and consistent tire on the track. I’ll state that again for clarity – if a tire warmer is used properly to set the carcass temperature to match the temperature which will be achieved on the race track, there will be no pressure rise once the bike goes out onto the track.

 

The proper method is to log tire temperatures using a probe (infrared devices only check superficial tire temperatures) after each track session and note the hot pressures as well. Certainly ambient air and track surface temperatures will affect this so you need to realize that early morning practice will not create the same increase as in the warmer afternoon session or race. If for example, the tire is working well at 80 C and a hot pressure of 24 PSI, you’d want to recreate that in the pits prior to heading out onto the track. In this way, the tire is stable. Be it 3 laps or 30, the temperature and pressure remain constant if you’ve predicted the hot temperature the tire will achieve during the event.

 

SAVING HEAT CYCLES

From a seat-of-the-pants experience, riders know that after heating a tire on the track and then allowing it to cool in the pits, it will lose grip. Not unlike cookies removed from the oven to cool, its during this cooling process that the tire hardens up. Tires are amazingly complex both mechanically and chemically, so I’ll try not to take the position of the tire engineer and will simply describe the effect an the benefits to be had. As tires cool, a change occurs that can be seen, measured and felt. On some tires, you can actually see a blue haze form over it as some ‘oils’ migrate to the surface and oxidation occurs. Putting the tire through these hot to cold cycles reduces the tire’s grip, hardens the rubber and reduces its useful life.

 

A tire warmer can keep tires hot or simply warm between track sessions and reduce the amount of heat cycles a tire goes through. If the tire is to see more than one track session, it makes sense not to allow the tire to cool all the way to ambient. This can extend how many sessions the tire can perform at near maximum grip. By operating in this manner the tire’s grip life can be increased.

 

Many professional teams utilizing warmers change the temperature setpoint to about 55 C when there will be an extended period of time between track sessions (over an hour). Then 30 minutes prior to the track session, the tire can be brought back up to operating temperatures again.

 

This process can also save a racer hard earned cash in the long run. The better you treat your tires, the longer they will last and the quality will hold up better as well.

 

EXTENDING GRIP LIFE

When the tire hardens from going to through the ‘heat cycles’, some changes are happening to the tire on a molecular level. The same is true of heating the tire. Depending on the circuit, rider, conditions and type of tire, the surface can be at extremely high temperatures upwards of 175 C due to abrasion. The tire will be heated due to the abrasion, deformation and hysteresis (wtf??) of the tire from actually driving the motorcycle and can be at operating temperatures in only a few laps, many times in 3-5 minutes.

 

This rapid heating seems to ‘heat shock’ the tire. During this process, molecular changes occur within the chemical composition of the tire. These chemicals which are the ‘lifeblood’* of the tire are being released quickly. This ‘lifeblood’ is being wasted by being spent too quickly while heating up the tire on the track too quickly. This can create a seat-of-the-pants sensation that’s felt by many riders each time they heat their tires on the track. The rider feels that the tire has come in, only to realize for few more corners that it is not quite ready as this rapidly heated high-temperature rubber is scrubbed off. Taking the time to think it through, you can realize that the carcass deep down will take longer to get to its stable or ‘heat soaked’ temperature, and this is why getting the tire to full hot pressure takes longer than just getting the surface hot.

 

When tires are heated with tire warmers, this sensation is not present and testing has found the ‘grip life’ of the tire is extended. The result is that by heating the tire slowly, this ‘lifeblood’ of the tire is not spent too quickly and ‘grip life’ is improved. For example, a particular tire that wasn’t preheated with a tire warmer may fall off in performance after 10-12 laps while maximum grip might have been achieved for 16-18 laps had a tire warmer been used.

 

SAFETY

Experienced riders know enough to take a few laps with caution before putting the hammer down and can get tires to operating temperatures on the track safely. However, there are those situations where a lapse of concentration or excessive emotion can cause an off track incident, due to cold tires. This can be dangerous to both the rider and his machine. It is necessary to ‘work the tires’ to generate heat and this presents an opportunity for error. The use of tire warmers not only gives you confidence in the tires right away, but reduces the chances of a cold tire incident.

 

TUNING WITH COMPOUNDS

Should a team have a choice of compounds or has to race in the rain, tire warmers can be set for the varying conditions. Rain tires, even though engineered to work well at low temperatures, do experience an increase of both temperature and pressure from use. I have seen MotoGP racing teams use the standard dry temperature of 80 C on rain tires, however, their own tire engineer and our experience shows that 55 C is enough to get the tire in the area of operating temperature and pressure. This provides first lap confidence and grip even in the wet. As for dry compound choices, the tire warmers can open up some options. For example, a rider is torn between 2 compounds, tempted to use the softer one for the grip in the early laps, but concerned it may not make it race distance. By using tire warmers (perhaps even at a slightly higher than standard temperature ie. 90 C, the harder of the 2 choices can be used so that less of a disadvantage is present during the opening laps and the tire will last the entire track session.

 

If you’re experienced with tire warmers, these issues probably seem like a review of the obvious. For many, we hope that this overview will open up the possibilities of how to manage your race tires better. Please don’t feel that tires once sold to the team cannot be influenced by your use or misuse of them. If you’re not currently paying attention to cold and hot pressures, hot tire temperatures, tire graining and wear patterns in addition to the standard information of compound and lap times, start now. A new tire, if made without defects, is ready for your input. Once delivered, its up to you how to store it, preheat it, inflate it, ride on it and decide when to allow it to cool down. Moving forward during the practice sessions and races really begins in the paddocks.

 

*(The mention of the tires lifeblood is an effort to describe the various chemicals, additives, elastomers, long link carbon molecules and other components tire companies use in their manufacture of racing rubber.)

[edmundino]

Great piece of information.

[ambasnakeman]

yo raptor,

 

havent u heard of scanner and OCR???

 

but still, thumbs up to your effort.

[Hartholomew]

Hey Raptor,

 

Good post as usual, great read!

 

Yo Amba!

 

Can borrow your tire warmers for round 4????

 

Please???

 

If not I got to use my lighter...

[ambasnakeman]

http://www.termorace.com/home_ita.htm

 

 

just saw this warmers today....as used by LCR team

 

measures tyre pressure as well

[ambasnakeman]

Hey Raptor,

 

Good post as usual, great read!

 

Yo Amba!

 

Can borrow your tire warmers for round 4????

 

Please???

 

If not I got to use my lighter...

 

lighter.....u can use ur rims to right after that????

 

dun worry la...i be at rd 4.....but something tells me we will be on the same grid? how?

[Hartholomew]

lighter.....u can use ur rims to right after that????

 

dun worry la...i be at rd 4.....but something tells me we will be on the same grid? how?

 

 

HOOOOOOOIIIIIIII!!!!??????????????????????????

 

You riding Superbike?

 

Oh my Lordy! Like that I have to feign injury... hahahha!

 

I got good excuse! I recently found out that I have a fracture in my right shoulder at CGH! I think it was from the time when I flipped my R1 at PG.

 

No wonder it hurt when I wank!

 

I take MC!!!!!

[ambasnakeman]

motogp support race they put 600s and 1000s on the same grid

[kingpet47]

now where can i get my hands on those tire warmers..............?

[NoLogicOne]

You guys could try to get from Andrew Morris at Mezzo. He had some tyre warmers for sale before I leave you guys man.....

 

I think I wanna spoil the track trends here in USA. Anyone wanna freight me tyres from SG so I could start a chain of LAB/HKL style tyre workshop here? I could confuse newbies that new cheap tyres are better than "warmer treated used tyres", lol....

 

Seriously, tyres are expensive here, but weird is that BT002Pro are priced cheaper than Power 2CT....duh?!?!

[Raptor]

Ya... I think it is really good to have tyre warmers.

 

Actually can serve 2 purposes... one is to keep the tyres warm prior to entry into the track.

 

The other purpose is.... if you have a fat tummy, you can wrap it around the waist while watching TV. Just like those slimming devices that use heat to melt away the fats... no need to go to the gym.

 

Whahahahahahahah!!!!!

[NoLogicOne]

Is there enuff powerpoint in PG to use the tyre warmers? Later the office trip, and they need to close off the track.

[kingpet47]

Is there enuff powerpoint in PG to use the tyre warmers? Later the office trip, and they need to close off the track.

 

hahahahaha..........now got electricity also no use......mayb i juz use the switch to charge my hp then.....

[pistolwhip]

 

and hysteresis (wtf??)

 

 

 

hand typed?

 

youre a saint...

 

anyway +1