Paintwork gets cleaned very frequently, but tyres not so much. Everybody who knows the word “detailer” or “valeter” probably knows how to safely remove contaminants from the surface of a vehicle. Even when glass is dirty, you’ll quickly see the streaks and your fingers will be itching to reach for the glass cleaner. Most parts of a vehicles gets cleaned frequently, and we have all kinds of products that help us keep our cars/bikes looking sparkly clean.
Why clean tyres
But how about rubber? How about the tyres you drive on? Sure, we know how to make them black again. But how many of us really spent much time cleaning them? There is dressing to make your tyres shine like the waxed dome of a bold man, other dressings leave a slightly more satin or matte finish on your car-shoes. But caring for your tyres is a little bit more work than just rubbing some slippery liquid on.
There will be those who are now thinking “Cleaning? Why?”. The answers are fairly simple:
- The amount of time that the rubber is exposed to the harmful contaminants is diminished
- It will look better on your car
- A dressing will last a lot longer on a clean tyre
- Not proven, but believed by many: a clean tyre will last a lot longer
What are you working with
As with everything regarding detailing, it really helps to know what you’re working with. The same goes for tyres. In this case it consists out of two parts: the tyre itself and the contamination you want to remove.
A tyre is a rubber ring that surrounds a rim. The two together are part of the component known as a wheel. Most of these tyres are inflated. The pressure prevents them from deforming too much and to hold their shape whilst also begin reasonably flexible. The material used for these tyres is made from a combination of several ingredients. These include synthetic and natural rubber, metal wire, fabric and several chemical compounds.
The creation of a tyre starts with raw materials such as different types of rubber with roughly 60 to 70% synthetic contents (including styrene-butadiene, polyisoprene, polybutadiene and halobutyl rubber), oils, carbon black and special chemicals. The rubber component is mixed with antioxidants and antiozonants to slow down aging due to sunlight and ozone. Carbon black and Silica can be used to reinforce the rubber and increase its and heat resistance. Sulphur is one part of the recipe that helps with combining the components successfully in the vulcanization process. The inside of the tyre is made from slightly different materials then the outside, mainly because of its low air permeability. The sidewalls are also made from a slightly different recipe because it does not need to meet the strict requirements needed for the thread. The part of the tyre most detailers work on is the sidewall of the tyre. It is highly recommended that you do not apply dressing to the thread of a tyre, or mess with it in another way. This can affect grip in a negative way and could cause dangerous situations! The sidewall of a tyre is mostly rubber that has been reinforced with fabric or steel cord.
The outer layer of rubber tyres is not completely solid, its outer most layer is capable of holding very slight amounts of contaminants because of its relative open cell structure. Due to the “softness” of the rubber, certain particles (like iron) are capable of sticking to the surface of the tyre. In general, tyres are exposed to similar contaminants as wheels: soot, mud, dirt, rubber, iron, oils, petrol, carbon deposits, mineral deposits, biological material, tar, tree sap and fluids used in/around engines. Once a contaminant is stuck to the surface, it is easier for other contaminants to get stuck on the first piece of contamination.
So ideally, you want to remove the contaminants mentioned above, without removing or damaging the materials used in the fabrication of the tyre. There is a grey area however, because a cleaner that removes grease will also have some effect on different types of oils. So it is very difficult to remove all of these contaminants without having any effect on other particles.
How to clean tyres
Cleaning tyres can be done with several different products. However, judging on the types of contamination it was decided to go for the following products:
- Snowfoam (same dilution ratio when used in a foam-lance)
- Traffic Film Remover (adjust dilution according to level of contamination)
- Tyre cleaner
- Vinegar (diluted 1:10 in a spraybottle)
- A very stiff nylon tyre brush (Tyre brush)
- A soft haired round brush (general round (unused) paintbrush)
- Gloves to protect the skin on your hands
Due to personal preference it was chosen to use the concentrated version of the products. This allows to play a little bit with the strength to meet the level of dirt and grime. The entire process can be done with the Tufshine Tyre Cleaner, but due to the cost of this product, it turned out cheaper to do some pre-cleaning with other products first.
Cleaning the tyre itself can be categorized into 3 sections:
- cleaning of the crud,
- deep cleaning,
- removing residue and testing result.
In my setup to demonstrate the steps I had the luck of having a dirty tyre lying around that had been removed from a rim that is being refurbished. Although I had a very good working space with a dismantled tyre, the products and the procedure should be the same with a tyre and/or wheel that is still attached to the car. The tyres used in this demonstration had been used for about 5 years without a single proper clean.
Cleaning the crud
During this process you aim to remove as much of the superficial dirt and crud as possible. Most of this contamination will be on the surface, and should be reasonably easy to remove. For this step I started out reasonably soft in order to see how the contamination would react to the products. I recommend to start with the least aggressive product. Only step up your game if the less aggressive product is not meeting your requirements.
- Rinse off the tyre to remove any lose dirt. Quickly rubbing it with the round brush while rinsing will help.
- Spray some snowfoam on the tyre and agitate it with the round brush. You’ll quickly notice how the suds turn brown.
- Rinse the suds off, and repeat the step until the suds stay white.
- Spray on some Traffic Film Remover, and agitate it with the round brush. You’ll notice how the suds become dark again. This is good, it is pulling off more dirt then the snowfoam did.
- Leave it for a few minutes to soak. Rinse off while using the brush to rinse off any residue.
Deep cleaning the tyres
- Keep using the snowfoam until the suds stop turning brown. This may take a while. In my demonstration it took 6 or 7 times until the suds stayed fairly white.
- If the snowfoam won’t turn brown anymore, spray some Traffic Film Remover on the tyre. Scrub well with the stiff tyre brush brush. Remember that Traffic Film Remover is not made to foam a lot.
- After scrubbing, rinse off the product. As long as the suds turn brown, you are not ready cleaning yet.
- Keep scrubbing with and rinsing, till the water and the suds stay clear.
- If you want to go even further, spray the Tufshine Tyre cleaner over the tyre. Wait about 10 to 20 seconds and then scrub thoroughly with the stiff tyre brush. Don’t be surprised to see more brown suds again. Tufshine Tyre Cleaner is especially formulated to remove the most stubborn contamination from rubber without affecting it in any negative way. It will loosen up contamination that the other products couldn’t touch.
- Rinse the tyre thoroughly while using the tyre brush
- Once the water won’t discolour anymore, spray a liberal amount of vinegar over the tyre and scrub well with the nylon brush. The vinegar will dissolve any soapy residue and is easily washed away by the water.
After you have cleaned the tyres, you want to check if the rubber is clean enough. The tyre needs to be dried first though. Remember that we didn’t spent time cleaning the thread, so your towel could still turn black when rubbing certain parts of the tyre. Only the marks from the sidewall really count. When testing the results of your cleaning, use a white towel. Any black marks are best seen on white towels. If you really want to set a new benchmark, spray a bit of -based glass cleaner on the towel before rubbing. You’ll notice from the squeaking sound that it reacts slightly different with the rubber surface. If your white towel turns black, the rubber isn’t clean enough yet.
Once you’re done with cleaning the tyres, it is time to make them look good again. I had the luck that these tyres where not being used for a week and where stored in a heated room. So I gave them a moderate coat of Supernatural Tyre Dressing every other day. This leaves a nice, natural satin look when quickly wiped with a dry towel. The 3 layers also add to the thickness of the coat whilst giving it time to fully soak into the surface of the rubber. The end result was a nice deep black and satin looking piece of rubber, wrapped around a freshly refurbished wheel. The tyre got a wipe with a washmitt and some normal shampoo every week, whilst not showing any fading of the deep and dark finish.
Points to take into consideration
Some might argue that cleaning the tyre with these products will remove essential particles that are not supposed to be removed from the rubber. These would include oils and could potentially accelerate the vulcanization process that is happening inside the rubber. Drying out the rubber could cause cracking of the rubber. The vulcanization process makes the rubber stiff and hard, and can also contribute to cracks in both the sidewall, shoulder and thread of the tyre. Apollo Vredestein in The Netherlands was presented with the question on how these chemicals would interact with the surface of the rubber.
Hi Vinnie, thanks for reaching out to Apollo Vredestein’s TIC (Tyre Information Center).
Let’s start at the basics of a car tyre. You are right in saying that the different parts from a car tyre are made from different materials. This is due to the different characteristics needed from those different sections. The sidewalls from a tyre are only several millimetres thick and is mostly rubber combined with fabric and sometimes steel wire or mesh.
During production many different materials are used, among those are carbon black and sulphur. Sulphur is used to influence the vulcanisation process and makes the rubber elastic. Carbon black is used in tyres as well for strengthening, which also contributes to their dark black colour. The black marks you get when you wipe a brand new tyre is due to soot that is formed as a by-product during production. It has no use and can safely be wiped off.
During the development the R&D department looks at many different variables, but these are all aimed at performance and safety. The effect dirt has on rubber is not taken into account at all. Off course the tyres get tested in wet conditions, and that water isn’t particularly clean. But the effect that dirt might have on the lifespan of the rubber is not taken into account in any way.
Now to get closer to your main question: the cleaning of a tyre. Simply looking at the theoretical side of the story, I can tell you that household cleaning products are not capable of having an effect on the rubber that is significant enough to have any impact on the longevity of the tyre. Most tyres don’t get old enough to show the long-term effect of these products. Heavy chemical products are different though, these can (if used frequently and in large quantities) have a negative effect on the tyre, but not enough to noticeably shorten its life. If the surface of the tyre is seriously damage (like a tear, or a chunk is taken out) there is a risk that these chemical products can loosen up small amounts of sulphur and/or carbon black. Which is an unwanted thing! However, in this case the removal of these components wouldn’t be your biggest worry.
Now to answer your main question, when cleaning a tyre it is important to remember to avoid any product that contains solvents or any oil-based materials. Oil can soak into the rubber and make it swell up. This can have a very detrimental effect on the quality of the rubber, and therefore the performance of the tyre and the longevity of the tyre. Normal cleaning products are not capable of removing the sulphur or carbon black from the rubber. There are no oils left in rubber to remove, these become part of the rubber during fabrication. However, this does not mean that these products cannot negatively affect the drying of the rubber. Some heavy products can dry out the rubber when frequently used, and even bring the natural vulcanisation process slightly out of balance. This increases the risk of cracking or structural failure of the tyre on the very long term. The sulphur or carbon black you mention in your e-mail does not disappear from the tyre in any natural way. It is a stable part of the rubber.
You also mention the use of a product called a “tyre dressing”, as far as we understand this refers to the products used to make a greyed out tyre look black again. We only known of 2 types of this product, the aerosol cans and the thick liquids. The aerosols should be avoided at all cost due to their solvent contents and they often contain oils. Same goes for the old WD40 trick (which we despise at the R&D department). The liquid is often suspended silicon in a water-based solution. These have no negative or positive effect on the rubber in any way. They are purely for cosmetic reasons. We don’t really see the logic behind them.
I wish you a lot of success with the article, and I hope these answers give you some insight needed for the article. If you have any further questions I look forward hearing from you.
Being realistic about tyre use and cleaning
Apart from the feedback from Vredestein, there is a different notation that should be taken into consideration. This is the limited age of tyres and its use. A tyre often won’t get very old. On average it is recommended by tyre companies to consider replacing a tyre when it is worn (less then 2mm thread) or when it is 5 years or older. These recommendations are made to make sure that the tyre performs within safe parameters and the chance of mechanical failure is minimized. According to questions asked at Apollo Vredestein, the tyre should (even with this type of maintenance) not crack or dry out within the average lifespan period of 5 years unless these products are frequently used in very large (and concentrated) quantities. So, how likely are you to see any problems caused by cleaning thoroughly within the safe period of use? These tyres are not likely to become very old, unless you are going to use them just for shows and meetings. Especially when you are going to use them to just visit shows, cleaning them with these products won’t be needed often. The good looks will be the main priority and they won’t get very dirty. So, the only tyres that will really need proper and thorough cleaning are the ones that are exposed to the elements. These are very likely to do some mileage anyway, and will not last much longer than the 5 year period. The tyres that might run the risk of being damaged by this cleaning method don’t last long enough to suffer from the potential damage you could be causing.
According to Apollo Vredestein the chemicals involved in the cleaning products mentioned, are not strong enough to seriously harm the chemical compounds used in the creation of tyres. The chemical resistance of rubber is fairly good to begin with. The contamination doesn’t penetrate the rubber very deep, nor does the cleaning liquid. The cleaning product is not left on the rubber long enough to do serious harm either. A last point is that the only component in the making of rubber that could potentially make the suds turn brown or black (apart from the contamination), is carbon black. Which is a component that makes up a very large part of the rubber, and is a stable part of the rubber that isn’t removed by normal cleaning.