Questions for a Tire Engineer: Throughout my career as a tire engineer, I have been asked a lot of questions and here are some of the interesting highlights that I would like to share.
1. Is 3-5 years old unused tires kept in warehouses away from sunlight still safe to use on the road?
–>In general, yes, it should be safe to use. 2 main points here
1st
The compound usually gets harder over time but this is usually not relevant for summer tires as their wet/dry braking distance do not differ much relative to the age of the tire. Winter tires are a different story as the compound softness plays a big role on ice/snow braking.
2nd
As you keep your tires in a high humidity condition there is a chance that you might see this phenomena “wax blooming”. The rubber compound usually contains antiozonant to protect tires from oxidation. Depending on your storage conditions migration could be triggered and you will see brown or waxy surfaces on your tire surface after keeping them for 1-2years in a hot & humid warehouse. This could lead to complaints and so on but this is perfectly safe and does not have an impact on performances.
2. What happens to my old tire after I left it at the tire shop? Do they recycle the tire?
Good question. There has been a big shift towards the sustainability topic in Europe as everybody wants to have a “circular economy” (Utopia dream..)
Right now half of the used tires are used for energy production through pyrolysis. The rest is either land fill or chopped to small pieces to be used as a filler in a composite system (benches, arm rest….) However as the tire compounds relies heavily on synthetic rubber which is derived from oil, it is not sustainable in the long run. Search for new materials which can be sustainable is on the way but so far neither it is cheap or provides good performances.
3. Are tires mostly made from Malaysia and Indonesia because these 2 countries have rubber plantations?
Having rubber production is a good advantage to have but not necessary. Tire production is based on tax incentives, labor cost & ease of export.
4. Assuming the same tires model, is there any difference between those made in China, Thailand, Indonesia, Malaysia?
So we know what different competitors use different rubber compounds for different regions. Like APAC, North America & Europe. But if you are talking about South East Asia specs, it should be the same. Of course every plant has its own tolerances and quality control but they should be relatively the same.
5. A 50% used ps4 vs a brand new made in china tyres e.g: Farroad FRD26 or westlake uhp, which will you choose?
This depends on your requirements. Are you looking for wet or dry? Wet performances actually deteriorate over tread depth which would make the china tire still attractive in terms of pure performances. The opposite is for dry as dry performance actually gets better when the tread depth decreases.
I don’t think PS4 had any performance over lifetime features like the new Michelin tirelines. What we have seen from China tires is that they are not good at solving target conflict. For example, they have outstanding wet braking but very bad mileage performance.
My personal opinion is to go for the used PS4.
6. Will upsizing from 185/55 R16 to 205/50 R16 affect fuel economy and car acceleration assuming using the same wheels. I believe this is due to larger size but from an online calculator it was way below (seems like the perfect size to upsize to) the 3 percent threshold (+0.25%) over 185/55 tires.
In terms of size effects, there is no big difference in terms of rolling resistance coefficient of your 2 sizes. <3%. If you somehow fit this on your vehicle assuming you have +20mm more space width, you are ok. Outer diameter only differs 2.5mm.
Regarding car acceleration, you have a wider front contact patch (205 vs 185) this is helpful in wet braking. But in terms of dry it should not matter
7. They say dragon fruit sap can patch tire up true ?
Definitely not true.
8. Are China made tires getting more competitive nowadays? If so, for an average daily driver, would it be wiser to go for China made tires?
From the results I see, they are catching up. Big brands such as ling long are relatively ok. But if budget is your constraint, you might as well go for the 2nd brands from the top manufacturers like Dunlop. They provide much more value than the China brands.
9. Any issues if I keep seeing road pebbles or small stones lodged on my tire threads? Leave it as it is?
These are usually fine as they tend to come out naturally. If you are hardworking of course it would be nice to pick them out but I predict the influence is very minimal.
10. Is the tire industry a good area of work for someone with product R&D background and an interest in cars? And is it a difficult field to get into?
Tire industry is all about target conflicts. An ideal tire engineer solves them with a range of complex material & technology while ensuring it can still be producible. If you like a challenge, the tire industry is definitely something you should explore. I think the key is to be very flexible in terms of learning as you will need mechanical, material, process & simulation knowledge to be a highly effective engineer. I would not say it’s difficult but the competition is hot for the premium manufacturers.