[indrangiri]

Thanks for all the details Dr.AD. You really know your BMW inside out :-)
Yesterday I was at Deutsche Motoren Service Whitefield to get the brake fluid replaced on my 320D and was waiting to collect the car. While browsing an article in the recent Autocar India, I saw an article on avoiding tyre punctures during highway drives

First point was to stay in the middle lane as far as possible in 3 lane roads to give us time to navigate any potholes and also avoid any debris on the road

Second point was interesting and wanted to check if anyone does follow this. It said that one must avoid hitting the brakes over a pothole.

When you hit the brakes, you're compressing your vehicle's suspension and causing your car to dip down in the front. This also means your suspension won't be able to efficiently absorb the shock of the pothole, so you won't have maximum suspension travel over the front wheels.

I know that this is difficult to implement when faced with a sudden pothole appearing from nowhere but good to keep in mind that if you dont brake well in advance, better to take the pothole at speed.

[Dr.AD]

Originally Posted by indrangiri

Thanks for all the details Dr.AD. You really know your BMW inside out :-)

Thank you very much for your kind words!

Originally Posted by indrangiri

First point was to stay in the middle lane as far as possible in 3 lane roads to give us time to navigate any potholes and also avoid any debris on the road

This totally depends on road to toad. For example, in the infamous potholed section near Tumkur, on the six-lane NH48, the middle lane is actually the worst as it has the most potholes. The leftmost lane has the least potholes and is actually safer to drive on. So it depends a lot on the specific conditions of the road and the space available around there.

Second point was interesting and wanted to check if anyone does follow this. It said that one must avoid hitting the brakes over a pothole.

When you hit the brakes, you're compressing your vehicle's suspension and causing your car to dip down in the front. This also means your suspension won't be able to efficiently absorb the shock of the pothole, so you won't have maximum suspension travel over the front wheels.

This is technically true. Same applies for tackling speed-beakers too. It is better to brake before reaching the speed-breaker, and not while crossing it. It is best to brake before it, then release the brakes and slowly crawl (As slow as possible) over the speed-breaker without braking. This minimizes the chances of underbody hitting. Applying brakes while on top of the speed-breaker is a mistake because that would cause the car to come lower down and increase the chances of hitting the underbody.

I know that this is difficult to implement when faced with a sudden pothole appearing from nowhere but good to keep in mind that if you dont brake well in advance, better to take the pothole at speed.

The problem with potholes is that you may not see them at all till it is too late. At that point suddenly applying brakes may not be an option too. At the same time, I do not think hitting those at full speed is safer either. Basically at that point is is just a bad luck, and it depends on a lot of other factors whether your wheels will survive that or not. Sharp braking at the very last minute, as well as not braking at all and hitting the potholes at full speed both are equally dangerous maneuvers.

[indrangiri]

Came across this ad from JK tyre on a "Self Healing Tyre". Anyone aware on how this works and could be gamechanger if priced at a reasonable premium over the conventional tubeless tyres.

This could also challenge the "Run Flat "Tyres as an alternate option if proven.

[sgm]

Originally Posted by Dr.AD

These are the RFT equivalent of the Micheline Primacy 3 ST (P3 ST) tyres that were so popular among sedan owners sometime ago. I still have those on my old SX4. However, thanks to the RFT version, which is a bit stiffer be definition, I found these P3ZP = P3 + RFT combo to be ideal for my ride and handling needs. These are great for long highway drives, and when the road gets rough, they provide quite a comfortable ride too.

On the other hand, the Pilot Sport 4 (non ZP version) which is available at about Rs. 12.5K is an outright performance oriented tyre. That will definitely offer a lot more grip than the P3 ZP tyres for sure. And as a bonus, it is a lot cheaper than P3 ZP (there is a good saving for a set of 4 tyres).

.

Thank you Dr AD for sharing your real world experience with RFT and the space saver. I have Bridgestone Turanza T005 RFT on my C220d. It is still going strong at 33k KMs and it should last till 40k KMs. I was considering to change to tubeless, to get a more comfortable and quieter drive, when it is time for me to get new tyres. Your story has given confidence that RFTs are a boon when you face a situation like what you have faced.

Micheline P3 ZP seems like a good option.

[Dr.AD]

Originally Posted by indrangiri

Came across this ad from JK tyre on a "Self Healing Tyre". Anyone aware on how this works and could be gamechanger if priced at a reasonable premium over the conventional tubeless tyres.

This is not something new. Such "tyre sealants" existed since a long time. In fact, here is an old thread on this: https://www.team-bhp.com/forum/techn...does-work.html (Ultraseal tyre sealant - Does it work?)

Also, IIRC, some new VW and Skoda cars came with such sealants applied in the tyre already, right from the factory. So this is definitely something not new.

There are some pros and cons of these tyre sealants, but I do not think they are an alternative to RFTs (nor do they even claim to be like RFTs).

Originally Posted by sgm

Thank you Dr AD for sharing your real world experience with RFT and the space saver. I have Bridgestone Turanza T005 RFT on my C220d. It is still going strong at 33k KMs and it should last till 40k KMs.

Micheline P3 ZP seems like a good option.

If you are happy with RFTs, there is no reason to go back to tubeless tyres. Micheline P3 ZP are much better than the Bridestone Turanza RFTs (they came as OEM on my 320d and I used them for 35k km, and they were very noisy). So yes, P3 ZP are definitely a good option for your car.

[ajayc123]

I expect the RFT to have stronger and more rigid sidewalls versus the tubeless tyres, in order to be able to run without air for a decent range. Is that a valid interpretation?

If this is correct, would it be appropriate to say that the RFTs sidewalls are more prone to damage vs tubeless tyres on bad roads because of higher rigidity?

[itwasntme]

Originally Posted by ajayc123

If this is correct, would it be appropriate to say that the RFTs sidewalls are more prone to damage vs tubeless tyres on bad roads because of higher rigidity?

You've just waved a red flag in front of multiple bulls . Wait for it!

On a serious note, I'd say RFTs are better equipped to take catastrophic shocks than corresponding tubeless tyres because of the more rigid sidewalls. On the flip side, there is anecdotal evidence that RFTs cause more alloy rim damage because they are less shock-absorbing, and thereby transfer a higher impact to the rims.

In my mind, what is moot is would a tubeless tyre survive a pothole or obstruction that damages a RFT? I'd say very unlikely. But the reverse could very well be possible!

Difficult choice!

[androdev]

Pothole impact has to be absorbed by suspension + tire. A typical BMW has stiff suspension and RFT - a reason for more frequent pothole related tire failures in BMW camp. Tubeless tires can deal with potholes better but when they do fail, they don’t offer the safety of RFTs. Pick your poison. No clear winner I feel.

[RubberGuru1113]

Originally Posted by ajayc123

If this is correct, would it be appropriate to say that the RFTs sidewalls are more prone to damage vs tubeless tyres on bad roads because of higher rigidity?

Originally Posted by itwasntme

On a serious note, I'd say RFTs are better equipped to take catastrophic shocks than corresponding tubeless tyres because of the more rigid sidewalls. On the flip side, there is anecdotal evidence that RFTs cause more alloy rim damage because they are less shock-absorbing, and thereby transfer a higher impact to the rims.

In my mind, what is moot is would a tubeless tyre survive a pothole or obstruction that damages a RFT? I'd say very unlikely. But the reverse could very well be possible!

Difficult choice!

My opinion - it all depends on the type of roads you frequent. RFTs are immune to impact damage - common in low profile tubeless tyres - basically the flexible sidewall causing an impact on the inner liner of the tyre in the case of a deep pothole and in an underinflated condition. But when driven continuously on bad roads, the rigidity of the RFTs’ sidewalls would cause a clean break of the sidewall because if the repetitive stress on the hard and brittle sidewall material, which in the case of tubeless tyres would have been absorbed without failure.

There are many documented cases with BHPians - https://www.team-bhp.com/forum/tyre-...e-upgrade.html (BMW 530d M-Sport (G30) : Tyre upgrade)

This is surely avoidable in the case of tubeless tyres, but the caveat being that one needs to be extra diligent about maintaining the correct pressure and top up the air well before receiving a TPMS alert.

[Dr.AD]

Originally Posted by ajayc123

I expect the RFT to have stronger and more rigid sidewalls versus the tubeless tyres, in order to be able to run without air for a decent range. Is that a valid interpretation?

Yes, this seems to be correct. RFTs do have a more rigid sidewalls compared to normal tubeless tyres.

If this is correct, would it be appropriate to say that the RFTs sidewalls are more prone to damage vs tubeless tyres on bad roads because of higher rigidity?

This is not necessarily correct. This is just one theory. RFTs are probably more likely to pass the impact to the rims, and thus, over a longer run, cause some rim bends (another problem common with BMWs). But the extra rigidity of the RFT sidewalls does not necessarily mean it should be more prone to damaging itself - if anything it should be the other way round.

The reason I stress on "not necessarily" is because these are complex questions and the answers would vary based on the angle of impact, nature of impact and damage (pinching of the tyres etc), air pressure, speed, and other engineering factors. Only a detailed simulation of certain failure modes on RFTs and non-RFTs of the exact same size and in exact same loading and other conditions would answer such questions.

In reality, it remains unknown as to which types of tyres will be more prone in given conditions for a given type of impact. It is not that normal tubeless tyres are invincible either. There are plenty of known examples of normal tubeless tyres having suffered severe sidewall damage in real-life driving conditions.

Also, note that regardless of type of tyre, the probabilities of damage are still statistically very small. In my case, I have faced this one single tyre issue in my 60,000+km of running of the BMW in all sorts of road conditions including many really bad roads. If I combine the driving experiences of 3-4 of my friends who often drive their BMWs with me, together, I would say we have seen 3 damages in more than 200,000km of running BMWs on typical Indian rural roads. So statistically, the odds are still very small.

In summary, regarding the probability of tyre damage, there is no clear winner. However, in case of the low probability event of an actual tyre damage, an RFT is much easier to live with than a non-RFT. You are totally safe even when a damage happens at high speed and you can simply drive to the nearest town even with zero pressure. For this reason, I would always choose RFTs for my BMW.

But others may choose normal tubeless tyre. That is fine too. There is no right or wrong answer here. One has to choose what they like based on their own preferences.

[ajayc123]

Originally Posted by Dr.AD

You are totally safe even when a damage happens at high speed and you can simply drive to the nearest town even with zero pressure. For this reason, I would always choose RFTs for my BMW.

But others may choose normal tubeless tyre. That is fine too. There is no right or wrong answer here. One has to choose what they like based on their own preferences.

My takeaway appears to be: if there is a sudden burst and pressure drops to zero instantaneously at high speed, the vehicle stability should be better with RFT, when compared to tubeless. Besides, ability to drive to nearest town (especially under hostile conditions) is also another important benefit. Definitely appears to be a lower risk option vs tubeless. I would vote for RFT.

[PapaBravo]

RFTs vs Tubeless is an endless debate. I am from the tubeless team. The ride quality, plushness, no noise & reliability are far more appreciated than ability to drive with a puncture. Keeping a tyre inflator/stepney in the boot mitigates that possibility as well.

Add to that the sidewall cuts due to minor potholes is something which is difficult for me to live with, especially while driving in Kolkata or on the Himalayan trips.

Also, unlike a belief that RFT give good performance, it should be good to note that BMW does not provide RFT but regular tubeless in their //M cars.

But in the end, it is all about expectation from the tyre & the roads that one ususally drives on.

Cheers

[Dr.AD]

New Brakes, Car Wash, and another Drive!

In all the tyre discussion above, I forgot to mention anything about a few other things. I think it is time to move on from the tyre discussion, and let me share some other updates.

Just about three months ago, I had replaced the front brake pads and the front brake discs. That time, CBS was showing about 5000km life still left in the read brake pads.

At the start of last weekend's Karwar drive, the rear brake pads life was down to 1800km. I assumed I would need new brake pads immediately after that drive which was about 1200km total (in the last 1500km or so the brake pad life decreases nonlinearly). However, thanks to the slow and careful return drive after the tyre drama, the brake pad life did not decrease much, and I still had 1200km of life left when I returned home. However, in preparation of the upcoming drives, I decided to change the brake pads anyways and not wait for it to go under 1000km of life.

With some short city runs, the brake pads life was down to 1100km when I went to Navnit BMW for new brake pads and brake discs:


Brand new discs (in addition to new pads) installed at the rear:


By the way, this was the third set of rear brake pads that I consumed in about 74,000km of driving (now installed the fourth new set). For the front pads, I had consumed the third set and installed fourth set at about 67,000km mark. Thus, on average, I am getting about 24,666km per set of rear brake pads, and about 22,333km per set of front brake pads. I think this is quite par for the course for a 320d.

In addition to the new brake pads and brake discs at the rear, I also got the car thoroughly inspected (by opting in for some kind of vehicle inspection package) and also got all the suspensions inspected after driving on the space saver tyre. There was also some "pre-monsoon vehicle check" campaign going on at BMW service center, and Navnit BMW offered me this check free of cost. Thankfully, the car passed all the vehicles checks quite well and everything was totally fine after the eventful Karwar drive. Overall, a great service experience at Navnit BMW. They did the job quite well and quite fast.

Although the brake pads under "CBS Service Requirements" were taken care of, now the next service requirement due is oil change in another 4700km:


This means that in about two months of time I will be back at the service center for oil change. My previous oil change was done in 05/2022, and therefore, the time limit for next oil change is 05/2023 as you can see above. However, I have already driven more than 6000km after the oil change in 05/2022, and thus, have only 4700km left on this oil which I will have to change in just about 2 months time now.

Now my car had new tyres, new brake pads, everything was inspected and passed the tests, and now I was eagerly looking forward to the next drive. However, the car was very dirty after the recent "monsoon drive" to Karwar, and in all the drama of tyre change, brake pads change etc, I had not got time for a proper car wash. So now I decided to give the car a thorough wash before the next weekend's drive.

I went to a new car detailing/wash place opened in HSR Layout, called "Next Level Detailing":



The car was very dirty and desperately needed a proper wash:



The car was properly washed with a high pressure water first:



Followed by a foam wash and another round of high pressure wash:



The car looking clean finally (this place did a good job and is certainly a nice place for a car wash; I will go here again for car washes for sure):


With brand new tyres, new brakes at the rear, almost new brakes at the front, and a nicely washed clean car, it felt lovely to drive the car! With this, I went for another weekend drive on the very next weekend since the eventful Karwar drive.

Drive to Wayanad, Kerala

This was a drive together with my close friend BHPian @robimahanta driving his BMW M340i. This was actually a family drive, with our respective better halves with us.

Unfortunately, this time Robi suffered a tyre scare, which he has described here. Quite strange that we had two cases of tyre troubles on two consecutive weekends after years of driving together without any trouble. Just some bad luck I assume.

Anyways, apart from this minor issue, in general we had a great drive and a great weekend trip. Roads to and within Wayanad are lovely, the locations and landscapes were beautiful, and the weather was quite perfect! We loved our weekend experience in Wayanad.

We stayed in LakeRose Resort (https://g.page/LakeRose?share) and it turned out to be quite a nice place. Thanks to our friend BHPian @KarthikK for discovering and recommending this resort to us from his previous trip there.

Our cars at the parking lot of this resort, with a lake in the background:



View from our room:



And the view from the restaurant:



Nice swimming pool, right on the shores of the large lake/reservoir:



Food in the resort was quite good, and we had several interesting dishes. However, let me sum up the food experience with this picture of the desserts (five desserts for the four of us was par for the course ):


We took an evening stroll in the Karapuzha Dam Park which was just about 200m away from the resort.

A view from Karapuzha Dam Park:



Some nice views around the dam:



Some late evening views around the lake back in the resort:



The swimming pool looked quite nice in the night:



Next day we drove to a nearby lake called Pookode Lake, and took a walk around the lake. View of Pookode lake:



Although we drove there in our BMWs, My Jeep Wrangler Rubicon (1:32 scale ) was with me, packed somewhere in my backpack, and I could not resist taking a few photos of my Jeep there while we chilled and relaxed in the resort the next day.

My Jeep in the resort:



It does not look out of place at all in that setting:



Finally, a parting shot of our cars before the return drive:


Overall a fun weekend with another memorable drive. Hopefully some more drives will happen soon.

That is all for now. Thanks for reading!

[Kochikaran]

Is it Normal for brake pad replacement at every 25K for a beemer?

[Dr.AD]

Originally Posted by Kochikaran

Is it Normal for brake pad replacement at every 25K for a beemer?

Yes, quite normal. In fact, the brake pad life I get on average is probably a bit more than normal. Most 3 series owners get about 20,000km on the brake pads. Anything more than 20k km can be considered a bonus :-)

For more powerful BMWs such as the M340i, just about 15,000km of brake pad life is the norm.