December

Cut Tires, Preps, and When to Use Them:

 

I could easily spend ten pages or more on the benefits of cut tires vs. non-cuts or specific tire preps and what works best and when. Rather, I'd like to cut to the chase and give the reader some insight as to what I've found to be "true" and successful for me. Mind you, there are a lot of snake oil salesman out there that would prefer I not tell you some of this information. Most would simply rather sell you their "magic elixir" that is "guaranteed" to make you "roll" faster, but the bottom line is, there is no one magic solution. Oh sure, there are good all-around preps, but just like exhaust pipes, there's never one that just blows the competition away, or we'd all be using it already.

There's a LOT to keep up on with tires in the karting game. Let's go over a few basic terms and nomenclature common to tires in karting.


Hot Box: A hot box is exactly what it sounds like. A box that is heated. We use a hot box in karting to heat the tires or maintain a constant temperature in them. Often times we use heat through the aid of a hot box, to stretch, or grow a tire to size it correctly. As the air inside of a tire is heated, it expands. Do you remember middle school science lab? This expanding air increases the pressure, (measured in PSI, or pounds per square inch,) and thus stretches the tire carcass outward to increase the circumference fo the tire. At the same time, the heat softens the rubber, making it easier for the belt or webbing in the tire to stretch and actually "grow" the tire. Hot boxes are also used to maintain tire temperatures at the track between race events. This retaining of heat reduces the number of heat cycles of a tire and keeps the tire ready for use at all times at or near race full operating temperature.

Tire Warmers: Tire warmers can be AC or DC powered electric blankets, if you will, for your tires. They are used to pre-heat your tires to a specific temperature, or to maintain tire temps between races. Tire warmers are often used in conjunction with tire preps to accellerate the prepping process and gain deeper penetration of the prep into the tread of the tire with the addition of heat.

Heat cycle: A heat cycle is one cycle of heating and cooling that a tire goes through. Typically, a tire will heat cycle each time it is raced. As the tire is used and abused, it induces heat; then as it rests or is stressed less, it cools to ambient air temperature. The extent or damage of heat cycling can be controlled somewhat by the abuse or lack thereof placed on the tire, and also through the proper use of a hot box or tire warmers.


Rotisserie:
Rotisserie, or "rolling" tires is exactly what it sounds like. You place your tires on a set of rollers which are very slowly turned by an electric rotisserie motor (similar to most high end barbeque grills). You typically place prep in a prep tray directly under the tires to prep them from the outside, or place prep inside of the wheel and tire assembly through the valve stem via a turkey baster or similar method, to "rotisserie" prep them from the inside out. Yes, you can "rotosserie" prep on the inside of the tire. Put about 4 ounces inside the right side tires through the valve stem, then roll the tires overnight - (a minimum of 12 hours for most preps). -- That's prepping from the inside.

External prepping: External prepping is exactly that....prepping the tire from the outside. This is most common to get the tire to "light", "fire", or "take off"....all common terms for getting a good grip for the first few initial laps of a race.


PRW:
PRW, or Pre Race Wipe, is a quick coat of prep applied to the outside surface or tread of the tire immediately before going to the grid or hitting the track. Common PRW's are preps that open the pores of the rubber or used in combination to expedite other surface preps into the tire tread.

Punching: Punching is "slang" for a durometer measurement. A durometer is a hardness tester for rubber tires....ie, an SS33 might duro "punch" 52. 52 being a degree of hardness on a particular durometer. Not all durometers measure the same, so care needs to be taken when comparing notes with fellow racers using a different durometer. Use of the same duromter at the same locations and angle of attack will give you the best, and repeatable, results. Your gauge will tell you if a specific tire is harder or softer according to your durometer. Don't be so concerned with the actual number, as long as it is in the ballpark. If in doubt, send your durometer back to the manufacturer or dealer and have it recalibrated.

Cut Tires: A cut tire is not what most people outside of karting would think. It's not something bad or detrimental to the tire at all. In fact, it is most often a good thing. Karting tires, especially in oval track racing are "cut" in a tire lathe. That is, a lathe built specifically to rotate a karting wheel and tire so that rubber may be cut or trimmed from it's surface. Cutting a tire in a tire lathe will true the tire and cut a particular profile into the contact patch for reduced or induced grip and sidebite, whichever is needed by the racer. We'll speak more on cut tires later in this article. (see below)

Different types of cutting:

Shoulders cut:....When you cut, or profile a tire, often times on a Burris, specifically, you remove excess rubber to round the shoulders of the tire to lighten the rotating mass, reduce heat slightly, and reduce sidebite.

Trued: Sometimes a tire is simply cut to be "trued". That is, simply making sure that it is perfectly round on the tire contact patch and tread surface. Although mounting is the most critical step in getting a tire to be "round", to be certain a tire is 100% concentric, often times it is cut to true it.

Sealed up: A tire that is sealed up, or sealed over, is typically a tire that has hardened up on the very outermost skin of the tread surface. This can happen when rapidly cooled during a race with above normal operating temperatures for the tire. As the tire cools rapidly, the outer surface will "cure" and become harder and may take a lap or two to scuff away this harder layer. Sometimes the tire will need to be refinished to bring it back to life again.

Refinish: A refinished tire may be ground or sanded....You typically do this on tires that have not been used in some time, or have been sealed over. Refinishing removes a thin layer of rubber from the tread surface of the tire to reveal a "fresh" layer, rather than a cured or "dead" layer that may have dried out over time. Refinishing a tire will reduce the tread depth slightly and reduce the wearability as well. Some racers will refinish a tire or simply grind a tire between races just for the "perceived" advantage, although if properly cleaned, this should not be necessary every night.


Needling
: Needling a tire is perforating the surface rubber of the tread with minute needle punctures, which allow prep to pentrate quicker and deeper in a shorter amount of time. It is also beneficial to opening up the rubber to gain a larger contact patch and to maintain tire temperatures.

Siping: Siping a tire is slicing the surface rubber of the thread with razor blade cuts. Cross siping builds heat in a tire quicker, while circumference siping generally helps to cool a tire once it is up to operating temperature. Siping should be avoided on very dusty/sandy track surfaces. Some kart tracks do not allow this, check with your track or sanctioning body's rules before siping your tires.

Seams: The seams are the mold separation marks from the factory that often remain even after racing the tire a few nights. The seams, many times, remain even after cutting and refinishing a tire. This is not uncommon at all, and should never be looked at as a way of determining tread depth.

Dot or Dot depth: Dot depth is just that; tread depth measured at the "dots". Most tires have small depth holes, or "dots," molded into the tread of the tire to accurately gauge the wear of a tire, or for our purposes, the thickness and sometimes the spring rate as well. Measured with micrometers, a new tire might measure between .090" and .100." Half used tires would measure ~.050" on the dots. On car tires, this is typically measured in 32nds of an inch. Most karters are more particular than the standard fractional english measurements, so I prefer to just use depth micrometers and get an accurate reading of the tread depth in thousandths of an inch.

Low rubber: Low rubber tires are tires that come from the manufacturer with less rubber on the tread. Of these, Maxxis and Firestone offer "low rubber" tires that need very little cutting if any to have them race ready. The trade off, obviously, is half the tread life, if that.

Date Codes: Date codes are simply the manufacturer's build date; the day that the tire was constructed at the factory. Additional information about the tire, such as mold number, carcass construction, rubber recipe, etc, may be indicated by the specific date code. When matching spring rates, it is often helpful to first match date codes on the tires to make a set (at least the right sides).

Spring Rates: Spring rates are a measurement of the amount of "compression" that the tire incurs. Simply put, how much height the tire compacts under a specific known weight. Higher spring rates typically free a kart up. Lower spring rates tighten a kart. Wheel width, tire design, (ie sidewall construction and tread thickness), durometer, and air pressure, (psi) also determines a tire's spring rate. Harder durometer tires, and higher air psi both increases spring rates. In general, for oval track racing, you want to focus your efforts on keeping the right side tires of an equal spring rate.


Mounting Tires:
The big key in mounting a tire is to mount it correctly the very first time. You will suffer much less aggravation if you follow these few simple steps. Wipe a thin film of dish soap on the entire bead of the wheel before we get started. Next, install the tire on the wheel by placing it on the back half of the whel at a 45* angle and "rolling" it on. Remove the valve core, and liberally lube the tire bead and wheel surface. Next, use a quality tire ring or tire band, such as the Jones Enforcer Rings. These are custom sized and machined perfectly round to ensure that your tire will mount up accurately and roll true. Besides, your tire cutter man will appreciate this if you are the one doing the mounting. For most racers, an adjustable tire mounting band is the more popular method of mounting karting tire although not as precise, it will work if you are careful and take your time to do the job right. If you are using an adjustable mounting band you will want to place the tire in the band and compress the band down to a pre-set size; generally 3/4" larger on the outside circumference of the tire band than the final desired size of tire circumference. For instance, if you want the final tire size to be 34 1/2", then set your tire band at 35 1/4" on the outside circumference measurement. Using a clip-on style air chuck, inflate the tire until it beads out solidly against the lip of the wheel on both sides. Once it has beaded, immediately remove the air chuck to let the air escape. Let the air PSI down to roughly 10 pounds, then replace the valve core and remove the tire from the tire band. Take a preliminary measurement at this point just for reference. It should be slightly larger than your desired final size at this point, but it will continue to decrease in size as the tire relaxes from being over-inflated. Let the tire set with 10# of air in it for 10 minutes. Then let the tire down to your race pressure. Let the tire set another couple minutes and measure it for final size. If it is real close to the correct measurement, you can "fine-tune" or "adjust" it with slight air pressure changes to stretch or shrink the tire slightly.

Shrinking & Growing Tires: First off, it is MUCH easier to "grow" a tire than to "shrink" one. Keep that in mind as you follow these steps. To shrink a tire to a specific size: Depending on how much you are trying to shrink the tire, try to avoid heat if at all possible. Try simply removing all of the air from inside the tire. Do this by removing the valve core and squeezing the tire down, then re-installing the valve core while compressing the air out of the tire. Next, submerse the entire wheel and tire assembly into ice cold water for as long as possible. Overnight is optimal if you have the time available. A 5 gallon bucket or small trash can works well for this project. If you still need to shrink the tire more, then you will have to resort to using heat. Place the wheel and tire assembly in a tire hot box or oven and heat them up, without the valve core installed, to around 180*. When you get them to that temp, put the valve core back in, and dunk them in ice water for ten minutes or more to "shock" them. You may need to do this a couple times to get the desired final size. If you are needing to grow a tire to a larger size, simply reverse the process, first, installing the valve stem and inflating to 10 psi. You may use a heat box (or oven) to heat the tire up. The heat will cause the air inside the tire to expand as it softens the webbing band inside the tire, thus "growing" or stretching the tire circumference. After the tie is up to 180*, you may remove it from the heat, and dunk it in ice water for a minimum of 10 minutes, again, to shock the tire. Be careful to stretch the tire with heat as minimal as possible. Once a tire is stretched, it becomes more and more difficult to get it to shrink back. Repeat if necessary.

More about cut tires:

Kart tires are commonly cut in a lathe. Popular tire lathes are the Amerac, Jones Tire Machine, Master Tire Center, SBC/VPR, and VMax tire cutters. Some shops use simply a brake or industrial gap bed lathe big enough to fit a karting wheel and tire. Often times a "cut" tire is simply a "trued" tire. That is, a tire that has been mounted and sized, then indicated in on a lathe before the tread surface is trued and made perfectly round. That's all good, but there is so much more. To see the real benefit of a set of cut tires, you need to have a "profile" cut into them. What is a profile? A profile is a prescribed contour of the tire contact patch and shoulder to better fit the user's particular requirements. Different tracks, different surfaces, different chassis, and set-ups all have to be weighed into the perfect "profile." Of course, experts have their preferred profiles, and one would be wise to subscribe to their fore-knowledge. While profiling tires can be an advantage, you are also removing rubber from the tire. This rubber removal serves several purposes. One, it makes the tire lighter. That is, the rotating mass is less, therefore, it will take less horsepower to move the mass. Another benefit is that the tire tread, and often times, the shoulder is now thinner, which disappates heat quicker. Getting your tires up to optimal temperature, then stabilizing the temps without over heating the treads yield quicker lap times. Still yet, the most often overlooked element of cut tires is the spring rate. Why is spring rate important? Well, the tires on your kart are essentially the "springs" of your chassis. The amount of sidewall flex, air pressure, and rubber hardness (durometer) all affect the ultimate spring rate of a particular tire. Thinning the tread or cutting the shoulder, will essentially change the spring rate of a given tire. Matching spring rates from one corner to another is yet a whole other facet of "true" tire set selection.
While it would be easy to simply grind the tire tread thinner; you would not get the benefit of cutting and truing the tire contact surface, getting a consistant tread depth and profile, or consistent spring rates all without inducing unwanted heat into the tire.
So are cut tires faster? For the most part, my answer is, yes. There may be the exception now and again. The current thin rubber Maxxis and YJF Firestones don't see much benefit by cutting the already too thin .040" tread depth thinner. You can still put a slight profile to the tire, and there is reason to believe that can and does make a difference. Some racing surfaces are more conducive to cut tires as well. High grip tracks in the southeastern US, where red clay and dirt-phault are commonplace, are where cut tires really excel. In the midwest, where racesare held on organic black dirt, cut tires don't make as much difference, because the tires don't build much heat or have the grip that most southern tracks provide. That's not to say that there isn't an advantage even on black dirt. It's just not as big of a deal unless the track has a higher degree of grip.
When choosing a set of cut tires, or a tire cutting shop, consider the cutter's experience. Is he a local that knows your tracks best? Is he familiar with your track surface and tire construction? Does he have the latest, or at least adequate machinery to cut the tires properly? What is his turn around time, and can he do custom cuts for your application, or simply a "one template fits all" guy? Cost is pretty much a no brainer, but do consider what each tire guy offers with their service. Typical tire programs might include: Tire mounting, sizing, cutting, balancing, and prepping. Most times, you get what you pay for. Ask around, shop around, but don't move around. Get on one tire program and stick with it. There's a lot to be gained by using the knowledge and experience of your tire guy. If you jump around from one tire guy to another, chances are, you will not benefit from the vast knowledge the guy can offer.

 

Thin Crust versus Thick Crust:

Ok, so we're not actually going to discuss pizzas and which is better, New York or Chicago style, but there are similarities in cut tires that we will delve into. Maxxis introduced a tire known as "low rubber" or .040 inch depth tread. This was in part an attempt to curtail cutting the tires in a tire lathe. Although, I'll agree that the benefit of cutting low rubber tires is minimal, it certainly hasn't stopped major tire cutting businesses and racers from having their low rubber tires cut to a specific profile, regardless of tread depth. So, when would we choose a low rubber tire from the factory over a standard tread depth tire cut down thinner, and why?

Generally, on midwest black organic dirt tracks that are generally low bite surfaces, the thick rubber tires are the way to go in my opinion. Low rubber tires seem to work best on high grip tracks that require little prep work. That's not to say that full rubber tires that have been cut aren't equally as good or even better than low rubbers. Here's why. On tracks that have low bite, we have to prep the tires significantly more than on high bite track surfaces. The extra rubber thickness, or deeper rubber allows the prep to penetrate and stay in the rubber rather than evaporate out so quick. It also holds the prep (like a thicker sponge) better for some reason. Even with thick or standard tread depth rubber cut to the same depth as low rubber tires, the cut thicks retain more prep and have more bite at the track. Some of this bite can be attributed to the tire shoulder as well, but either way, it seems that thick treads cut down are the way to go in the midwest and low bite surface tracks specifically. Think about it this way, if you have more material to work with before cutting the tire, you can have more control over the entire profile of the final cut tire than starting with the low rubber tires to begin with. The preferred profile on a Maxxis t-3 for here in the midwest will have more rubber on the edges of the tire which results in higher side bite than the thins.

Another reason to choose thick rubber over thins is if you are on a budget. Obviously, the thicker rubber tires will wear longer than the thins. Even if you choose to have them cut, you can cut them .060" rather than straight to .040", which will yield another couple races out of the tire for most applications. The thin rubber also have a thin shoulder, so typically, you see the edges wear through to the cords before the rest of the tire is used up. This may also be indicative of a tire that is the wrong profile for your application, stagger, cross, etc. Even on high bite aggressive tracks, it may be better to start with thick rubber tires, then have them cut down, leaving a little more meat on the shoulders simply to allow a better wear characteristic, ie a tougher shoulder that will withstand the abuse of a track with high grip that induces higher tire temperatures and aggressive tire wear.

 

What is all this to-do about tire prep?

The big thing to remember about preps is that some of them are very dangerous. That's right, forget about the MSDS sheets or the warnings on the label, think about your own safety instead of relying on the retailer or manufacturer of said tire prep. The end user is the one that undoubtedly takes the ultimate responsibility and risk in how the tire prep is used. Whether used properly, or improperly, the choice is up to you. Many preps contain flammables. Many are quickly absorbed (ie carcinogens,) through the human skin. Most all have an airborne danger that can cause respiratory problems if inhaled. I could go on and on...Bottom line is: Be sensible. Be safe!

 

Popular tire preps:

Let's break down the most popular preps that we offer and see what can be understood about them and their specific applications a little better.

Pink Panther

Often called, "red", or other versions of the color red, Pink Panther prep works well as a topical, "surface prep". Pink Panther is one of the least harsh of tire preps avialable on the market. For this reason, Pink Panther makes an excellent mild softener/conditioner, (will not dry out the rubber,) that induces natural resins back into the rubber. Paint it on about ten minutes before you grid for a good "temporary" take off, (1 or 2 lap advantage).
Pink Panther prep can also be soaked into the tread in advance for deeper penetration and will soften the duro. if saturated over time. You can paint the prep on one coat at a time until it stops absorbing, then wrap the tires in aluminum foil to keep them wet, or rotisserie prep them from the outside for 2-8 hours, (depending on the amount of penetration you need,) 24 hours before race time. You can then wipe them with surface prep or a PRW at the track to maintain them.
You can also prep the tires from the inside out (works best for storage over the winter or to drop the duro. significantly). About 4 ounces inside of right side tires, and 3 ounces inside left side tires...Roll a minimum of 12 hours to assure complete absorbtion. For long duration storing of your tires, simply bag them up as a set (wheels and all) in a large black trash bag. Remove as much air as possible from the bag, then tie it tightly to prevent the elements from affecting your tires.
The introduction of heat to the tires as Pink Panther prep is applied will aid in the saturation of the prep into the rubber, but is not necessary. Some racers experience additional benefits of prepping in a hot box or by using heat to expediate the prep into the rubber. Your results may vary. Be careful not to expose Pink Panther prep to an open flame or ignition source, as it is highly flammable.
Pink Panther works best on dry slick, low bite, hard packed, loose and dusty track surfaces. It also works well on cold, wet or damp tracks that retain moisture when a softer durometer tire is needed. Pink Panther is a great all around prep that does not dry out the rubber, and actually conditions the tire by adding natural resins back into the rubber. It aids in keeping tires moist when not in use, (great for tire storage), and brings new life back to old dry tires.
Pink Panther is NOT an aggressive prep that will easily ruin a tire, (although ALL tire preps should be used with caution.)
Special care should be taken when ANY prep is applied. Be sure to use in a well ventilated area with no open flame as Pink Panther is very flammable. Pink Panther needs to be stored in an all metal container. It will quickly dissolve plastic bottles common to some other preps available in karting.

Gold Flash

Gold Flash, "'ol yeller", or more commonly called "goat pee", is a common chemical used in the printing industry. Goat Pee; who exactly first coined that name? Disgusting, and it both looks and smells disgusting! It is obtained through most major kart shops in quart and gallon jugs and is relatively inexpensive. There are several "cut" versions of this prep in circulation and should be avoided. Pure Gold Flash is the real thing and can be cut down if needed by the end user. Gold Flash (Goat Pee) softens the tire and there's rarely anything that works better on moist track surfaces. It is easy to over prep using Gold Flash though. If you are rotisserie prepping, be sure to prep lightly and in several layers or coats, so as not to ruin a good set of tires. Gold Flash will drastically drop the durometer (softness) of your tires and could render them useless if over-prepped. I recommend 3-4 oz. rolled inside the right side tires, and 2-3 oz. rolled inside the left sides to drop the tire's tread 10 to 15 durometer points. Be careful to thoroughly roll the tires. My program insists on 12 hour roll in periods for any prep going on the inside of a tire carcass. Some may take longer! You need to make very certain that the prep is completely absorbed into the tread of the tire and that the prep doesn't "puddle up" in the bottom of the tire as it sets on a tire rack. If you are surface prepping, Gold Flash can be rolled in about 4 hours, and often times even less, depending on the level of saturation and penetration you are looking for. My typical surface rotisserie prep would start at least 24 hours before race day, and consist of just enough prep to get the duro where you want it on race day, then wrap the tires up. Once you get to the track, you can unwrap the tires, and wipe the tread surface with Gold Flash just to touch them up. If you are wanting to significantly drop the duro (softness) of the tires, start your prep program 4 or 5 days in advance of race day.

Wintergreen

If it's green and has a strong health club odor, it's likely wintergreen. Now, there's a big difference between wintergreen and Simple Green. If you don't know the difference, just take a whiff of each. Wintergreen is a tire softening prep, whereas Simple Green is simply a cleaner. What exactly is wintergreen prep? Man, it sure does smell funny. (As if the others don't.) This is a deep penetrating prep with a strong wintergreen odor. It works good for dirt and asphalt applications, and is especially good if the track gets some dew on it between races. Its best use may be on cold or damp pavement tracks. Apply one to several coats of Wintergreen allowing the prep. to complete absorb between coats. You can also wrap the tires in plastic for a deeper penetration overnight. A few ounces rolled inside the tire will also soften the duro, compound, when used in a tire rotisserie. Wintergreen also makes a very good "disguise" of your current tire prep program with it's strong odor. A light wipe at the track will do very little to enhance or detract from the performance of your tire, but it will most certainly get the attention of your competitors.

Green Dragon Grip

There's another kind of green that's been taking the karting prep world by storm recently, and it's an environmentally friendly(er) tire prep called Green Dragon Grip. Green Dragon Grip, GDG,or Dragon as it is more commonly called, is most often used as a PRW, but can also be used similarly to Speedy 500, Acrysol, and other agents to reduce or cut/thin other preps. GDG is gaining popularity because of it's "greener" (pun intended) characteristics in a world of very harsh chemicals used in karting today. GDG is less agressive than it's counter parts, Acrysol and Speedy 500, but has much of the same effect without the strong odor and quick evaporation rate. For this reason, Green Dragon Grip works awesome as a pre-prep cleaner. Typically, you would wash the excess loose dirt from your tires with normal soap and water. Dry the tire tread surface, then rub in Green Dragon Grip with a lint free cloth. The tires will clean up very well and be immediately ready for any additional prep that you desire to apply.

Acrysol

Acrysol is a great tire cleaner to remove exisiting preps from the tire surface. Simply rub Acrysol into the tire tread with an absorbent rag. Be sure to wear rubber gloves and use only in a well ventilated area.
Acrysol is also a great pre-prep wipe to open up the pores of the rubber and let other preps penetrate the tire quicker and deeper.
You can also use it as a pre-race wipe right before you go on the grid; it will help the tire "fire" for the first few laps and is preferred on hard clean racing surfaces (not dusty).
Acrysol can also be used to dillute certain preps so they're not as aggressive, (ie Creosote, Gold Flash, Hot Lap, etc.)
Acrysol is NOT intended for long duration or deep saturation use. Use of Acrysol by itself will dry rubber out and make it like a pencil eraser over time, (softer, but also wear quicker.) Acrysol should not be used in conjunction with heat, as it is extremely flammable. Acrysol also has an extremely high evaporation rate and should only be used internally if combined with another prep which induces resins or oils back into the tire. (Popular combinations might include Black Max, Gold Flash, Hot Lap, Marvel Mystery Oil, creosote or transmission fluid.)

Speedy 500

Speedy 500's use is essentially the same as Acrysol. It makes the perfect tire cleaner to remove exisiting preps from the tire surface. Simply rub Speedy 500 into the tire tread with an absorbent rag. Be sure to wear rubber gloves and use only in a well ventilated area.
Speedy 500 is also a great pre-prep wipe to open up the pores of the rubber and let other preps penetrate the tire quicker and deeper. We especially like to use it ahead of Pink Panther and Gold Flash.
You can also use it as a pre-race wipe right before you go on the grid; it will help the tire "fire" for the first few laps and is preferred on hard clean racing surfaces (not dusty).
Speedy 500 can also be used to dillute certain preps so they're not as aggressive, (ie Creosote, Gold Flash, Hot Lap, etc.)
Speedy 500 is NOT intended for long duration or deep saturation use. Use of Speedy 500 by itself will dry rubber out and make it like a pencil eraser over time, (softer, but also wear quicker.) Speedy 500 should not be used in conjunction with heat, as it is extremely flammable. Speedy 500 also has an extremely high evaporation rate and should only be used internally if combined with another prep which induces resins or oils back into the tire. (Popular combinations might include Black Max, Gold Flash, Hot Lap, Marvel Mystery Oil, creosote or transmission fluid.)

What's this I hear about creosote?

Black Gold, Black Sand, Black Magic, Black "just about anything", will be a creosote based tire prep. Now, you may already know all about creosote, or you may not. IF you do not, then I suggest you do a little research online. Creo can be nasty nasty stuff, but it can also really hook up your kart. If used correctly, it can definitely make you faster. If used incorrectly, it will most certainly lock you down, or even worse, ruin a good set of tires. Creo is used primarily when no other prep will do. Creo is the "solve-all" grip prep that will lock down about any kart on any track surface, as long as it does not have dust lying on the groove. On a cool, damp, or wet surface, it's the ultimate hook-up. For that reason, creo is often referred to as glue, rather than a prep. Creo can be cut with just about anything. We have had huge success running on coke syrup indoors on creo and kerosene cut 50-50. Creosote is also often cut with Acrysol, Speedy 500, laquer thinner, mineral spirits, naptha, Hot Laps or Hot Laps II, and many more. One of our more popular blends makes one of the best wet track low grip tire preps available today, Black Gold.

Black Gold

Black Gold is one of the best grip preps for midwestern black dirt tracks and is especially beneficial when used on Buirris tires on low grip tracks where you just can't get the tires soft enough or gain enough tire grip. When the track has moisture in it, Black Gold is the way to go. If the track starts dusting up, then we switch to Pink Panther. Black Gold is equally successful on very low grip clean dry track surfaces. The ultimate condition being "clean". Black Gold is intended for a quick lauch surface prep to aid in firing the tire the very first lap of a race. It is best applied just minutes before going to the grid. For a 2-5 lap advantage, roll or spray Black Gold onto the tire tread within, but no more than, ten minutes prior to going to the grid. Applying Black Gold earlier in the week, or over saturating the tire, will undoubtedly kill the tire. If you are wanting to soften the tire considerably, consider rotisserie prepping from the inside using Gold Flash, or Atomic Orange. Both will soften the tire, while Atomic Orange will also put needed oils back into the rubber.

Black Max

Black Max is one of the best grip preps for extreme grip on midwestern black dirt tracks and is especially beneficial when used on Buirris tires on low grip tracks where you just can't get the tires soft enough or gain enough tire grip. Black Max is also our favorite indoor prep on coke syrup. When the track has frozen over or is "wet", Black Max is the way to go. If the track starts dusting up, then we switch to Pink Panther. Black Max should be avoided if the track gets dusty or marbley at all. The ultimate condition being "clean, cold, and damp." Black Max is intended for a quick lauch surface prep to aid in firing the tire the very first lap of a race. It is best applied just minutes before going to the grid. For a 2-5 lap advantage, roll or spray Black Max onto the tire tread within, but no more than, ten minutes prior to going to the grid. Applying Black Max earlier in the week, or over saturating the tire, will undoubtedly kill the tire. Never roll Black Max internally (inside the tire.) If you are wanting to soften the tire considerably, consider rotisserie prepping from the inside using Gold Flash, or Atomic Orange. Both will soften the tire, while Atomic Orange will also put needed oils back into the rubber

Atomic Orange

Atomic Orange is a fairly harsh prep that softens the tire's rubber dramatically, while not drying it out. Used mainly as an internal prep, rolled inside of the tire, Atomic Orange can also be applied to the surface of a tire for quick adhesion and immediate penetration. Atomic Orange's sticky feel will gain much needed grip early in a run, while only lasting as deep as the penetration. Atomic Orange can be rolled in deeply, with caution being taken not to soften the rubber too much.

 

Other popular tire cleaners:

Simple Green, Pro Blend, Trac Tac & others

Simple Green is a popular cleaner / degreaser that can be effectively used to clean your tires between races, or before you load up to head home for the night. Simple Green has tons of uses, from air filter cleaning, to degreasing chains. This makes Simple Green an obvious choice for the budget kart racer wanting to clean his tires without forgoing the money to buy a commercially made and marketed tire "specific" cleaner. Of the many popular tire cleaners available, Pro Blend has probably one of the best I have used. Equally as effective is the Blue Tire Wash from Trac Tac Products. Both do a superior job to Simple Green or waterless hand cleaners and degreasers. The Pro Blend Tire Cleaner also makes an excellent accelerant for other preps to penetrate the rubber. Blue Tire Wash contains an additive known by the manufacturer as DRT, or "dirt repelling techonology".

Other preps worthy of mention:

Hot Lap and Hot Lap II are both very good preps available from Pro-Blend and most major kart shops. I especially like rolling HL II on the inside of my tires along with a surface prep of Pro-Blend's Victory Lap for a great "predictable" grip, especially with Maxxis HT-3's. Victory Lap makes a great topical solution prep for that first lap grip that predominantly natural rubber tires like Hoosier and Vega area known for. Hot Lap works real well in conjunction with Marvel Mystery Oil when rotisseried as well.

Trac Tac has some great products as well. One advantage of them is that they are all relatively easy on the rubber, that is, not harsh. I have already made mention of their Blue Tire Wash, which is pretty good stuff, but they also offer Black Sand (not creosote based) prep for the dry slick dusty surfaces, and something they like to call DRT in their pre-race wipes. DRT is "dirt repelling technology", and this stuff is pretty cool. If you've ever looked at your competitors tires and wondered why they were so black, while yours picked up dust, this just may be the product they are using. DRT actually keeps the dust from sticking to the tire. This is especially nice if you need to roll your kart to the grid before entering the track.While DRT is pretty amazing, it is NOT to be used with some of the more popular preps. DRT preps are best used with the Trac Tac product line. You would be wise to consult with Trac Tac directly for specific interactions and instructions.

Venom Juice. Venom Juice is the product of Eric Rendleman, and is very much along the same lines as Trac Tac Products, as it is made in the same plant from my understanding. Eric's experience with tires and prep is worthy of a mention here. Although we do not promote his products, they are a high quality option available to karters everywhere. Please contact Eric directly with any questions reguarding his products.

Palmetto Speed Shop. Palmetto offers a wide variety of preps and are available in smaller quantities to make them affordably priced. Their online presence is well established, and customer service is in high regard. I have only ever tested a few of their products, and was pleased with the results. Please contact them directly if you have any questions or to see their entire product line.

Gecker Preps. Sheldon Gecker has introduced his own line of tire preps as well. His success at some of the bigger indoor races cannot be argued with, so his preps obviously deserve a mention here. Please contact Sheldon directly for his preps.

Track Claw: Track Claw has been around for years and has been used in stock cars mostly until the karters got ahold of it for use in kart tires. It is readily avilable and can be contacted directly for technical information.

 

 

Of course, there are MANY other preps available out there to karters. Choosing the correct one shouldn't be as hard as some make it out to be. It takes a lot of time, patience, and most importantly in the end, experience, to find what works best for your particular application. If there's one thing I advise all my customers, it's to get on one person's/shop's/manufacturer's regiment, and stick with it. You can get really out in left field when you start mixing chemicals incorrectly, or in conjunction with another that was not meant to be.

 

 

If you have any questions, please feel free to contact us directly.

Thanks,
Carlson Racing Engines / Vector Mfg.
www.CarlsonMotorsports.com
(765) 339-4407

 

 

 

 

 

 

 

 

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bcarlson@CarlsonMotorsports.com