Tyre self sealant

[Drake2007]

Ok, thank you. I'll go check. It seems to be very cheap, R65 at makro. To plug a tyre at TWT cost R125 plus the inconvenience of a flat. I'm very surprised that I've never heard of this.

R125 is daylight robery! local garage does ours for R40.

 

[Ockie]

 

[3WA]

R125 is daylight robery! local garage does ours for R40.

Lots of rural places will charge R100 or more, reason being, if you're there enquiring, circumstances dictate that you'll be willing to pay it.

 

[SauRoNZA]

Chances are it never penetrated the tyre properly because you should have seen the goo flow out then to plug it.

 

[Geoff.D]

My daughter is a keen mountain biker. She moaned like anything last week for being quoted R100 per mountain bike wheel.

 

[Craig_]

The product in my emergency kit is called

STOP LEC.

Used for trucks, cars and bikes and cycles.

Here is quite an interesting article about TPMS systems. It sounds as if your car is fitted with the indirect TPMS version, which would be unaffected by these compounds?

http://www.bridgestonetire.com/trea...ire-pressure-monitoring-system-how-tpms-works

Would still check what your car manual has to say about it.

It uses ABS apparently.

If you drive over a sharp object like a nail in a large plank you'll not know that the sealant has done its work because the nail is not embedded in the tyre so you will blissfully continue to cruise at high speeds.

This doesn't sound like a good idea to me.

It would be quite important to regularly check your tyres with this in place. I checked because I heard a sound coming from the back of the car for a few seconds, and then it went away.

Chances are it never penetrated the tyre properly because you should have seen the goo flow out then to plug it.

It definitely went right through the tyre. But up to now there has been absolutely no pressure loss at all. Might take the car in on Friday to have the tyre checked out as I'm doing a long distance trip this weekend with it. Don't want to risk the tyre letting go suddenly at highway speeds.

 

[SauRoNZA]

It uses ABS apparently.



It would be quite important to regularly check your tyres with this in place. I checked because I heard a sound coming from the back of the car for a few seconds, and then it went away.



It definitely went right through the tyre. But up to now there has been absolutely no pressure loss at all. Might take the car in on Friday to have the tyre checked out as I'm doing a long distance trip this weekend with it. Don't want to risk the tyre letting go suddenly at highway speeds.

If you are trusting silicone in the first place what’s the real difference with liquid silicone?

It can’t just suddenly “let go”.

It might slow puncture deflate but that’s about as exciting as it will get.

If it’s not leaking and has maintained pressure there is no reason to worry about it.

Also TPMS and ABS have nothing whatsoever to do with each other.

One sits inside your tyre on the valve attached to the rim, the other is part of your braking system.

 

[Foxhound5366]

SauRoNZA, the TPMS in BMW doesn't have anything in the tyre. It uses the tyre's rotational speed to detect if one has started deflating and is rotating at an abnormal speed. You have to initialise the system every time you too up your tyre pressure.

 

[Craig_]

If you are trusting silicone in the first place what’s the real difference with liquid silicone?

It can’t just suddenly “let go”.

It might slow puncture deflate but that’s about as exciting as it will get.

If it’s not leaking and has maintained pressure there is no reason to worry about it.

Also TPMS and ABS have nothing whatsoever to do with each other.

One sits inside your tyre on the valve attached to the rim, the other is part of your braking system.

Was just my clumsy way of referring to the below. You might be right about the slow leak thing. I will check with a workshop anyway before the weekend.

Indirect TPMS do not use physical pressure sensors but measure air pressures by monitoring individual wheel rotational speeds and other signals available outside of the tire itself. First generation iTPMS systems are based on the principle that under-inflated tires have a slightly smaller diameter (and hence higher angular velocity) than a correctly inflated one. These differences are measurable through the wheel speed sensors of ABS/ESC systems. Second generation iTPMS can also detect simultaneous under-inflation in up to all four tires using spectrum analysis of individual wheels, which can be realized in software using advanced signal processing techniques. The spectrum analysis is based on the principle that certain eigenforms and frequencies of the tire/wheel assembly are highly sensitive to the inflation pressure. These oscillations can hence be monitored through advanced signal processing of the wheel speed signals. Current[when?] iTPMS consist of software modules being integrated into the ABS/ESC units.

 

[SauRoNZA]

SauRoNZA, the TPMS in BMW doesn't have anything in the tyre. It uses the tyre's rotational speed to detect if one has started deflating and is rotating at an abnormal speed. You have to initialise the system every time you too up your tyre pressure.

And where do you think it gets that rotation information from?

https://www.ecstuning.com/News/BMW_...320_328_335_Activehybrid_2012_2013_2014_2015/

The sensors in the wheels of course.

It's a bit silly that you need to initialize it whenever you topup. It should be the very first diagnostic that runs after the first coupe of meters from a fresh start.

Much like ABS.

 

[Craig_]

And where do you think it gets that rotation information from?

https://www.ecstuning.com/News/BMW_...320_328_335_Activehybrid_2012_2013_2014_2015/

The sensors in the wheels of course.

It's a bit silly that you need to initialize it whenever you topup. It should be the very first diagnostic that runs after the first coupe of meters from a fresh start.

Much like ABS.

I definitely do not have sensors in my wheels, but I do have a TPMS.

Edit: that is a US site and I think indirect TPMS is not used in the US.

 

[Foxhound5366]

And where do you think it gets that rotation information from?

https://www.ecstuning.com/News/BMW_...320_328_335_Activehybrid_2012_2013_2014_2015/

The sensors in the wheels of course.

It's a bit silly that you need to initialize it whenever you topup. It should be the very first diagnostic that runs after the first coupe of meters from a fresh start.

Much like ABS.

Ok, it wasn't clear what you referring to when you said that the TPMS was in the tyres. The rotational sensors in the tyres are also used by the ABS and ESP systems, right?

 

[SauRoNZA]

Was just my clumsy way of referring to the below. You might be right about the slow leak thing. I will check with a workshop anyway before the weekend.

Indirect TPMS do not use physical pressure sensors but measure air pressures by monitoring individual wheel rotational speeds and other signals available outside of the tire itself. First generation iTPMS systems are based on the principle that under-inflated tires have a slightly smaller diameter (and hence higher angular velocity) than a correctly inflated one. These differences are measurable through the wheel speed sensors of ABS/ESC systems. Second generation iTPMS can also detect simultaneous under-inflation in up to all four tires using spectrum analysis of individual wheels, which can be realized in software using advanced signal processing techniques. The spectrum analysis is based on the principle that certain eigenforms and frequencies of the tire/wheel assembly are highly sensitive to the inflation pressure. These oscillations can hence be monitored through advanced signal processing of the wheel speed signals. Current[when?] iTPMS consist of software modules being integrated into the ABS/ESC units.

Well that's not TPMS (as it cannot actually tell you the tyre pressure) but rather just a flat tyre monitor.

And yes that exists but as above it can't actually tell you the pressure, just that there's potentially a flat.

Which makes sense if it's using a run flat tyre system as most BMW's do.

 

[SauRoNZA]

Ok, it wasn't clear what you referring to when you said that the TPMS was in the tyres. The rotational sensors in the tyres are also used by the ABS and ESP systems, right?

It's two different things.

Flat Tyre system would use the ABS ring and yes it can count the rotation speed based on that and pick up a variance, but would only give you a flat tyre warning.

Tyre Pressure Monitoring System will have sensors inside the tyre and will read you the actual pressure in bar/psi/kpa.

It think it's just a mixture of terms being used under a single banner.

Probably find on the lower end BMW's it would be just a flat tyre warning system and the higher end models full blown TPS.

 

[Foxhound5366]

Well that's not TPMS (as it cannot actually tell you the tyre pressure) but rather just a flat tyre monitor.

And yes that exists but as above it can't actually tell you the pressure, just that there's potentially a flat.

Which makes sense if it's using a run flat tyre system as most BMW's do.

Aah yes, Sauron isn't going crazy, there are indeed some systems with pressure sensors inside the wheels: http://techcenter.mercedes-benz.com/en_ZA/tyre_pressure_monitoring/detail.html

Very spiffy.

 

[Craig_]

Well that's not TPMS (as it cannot actually tell you the tyre pressure) but rather just a flat tyre monitor.

And yes that exists but as above it can't actually tell you the pressure, just that there's potentially a flat.

Which makes sense if it's using a run flat tyre system as most BMW's do.

It doesn't tell pressure yes, just says one of the tyres has low pressure (can't say which one), or says a tyre is flat. The manual refers to it as TPMS as well as very other document I can find on the internet. That's why I also referred to it as TPMS.

 

[Foxhound5366]

It doesn't tell pressure yes, just says one of the tyres has low pressure (can't say which one), or says a tyre is flat. The manual refers to it as TPMS as well as very other document I can find on the internet. That's why I also referred to it as TPMS.

It's ok Cr419. Peasants like you and me can't understand the likes of Sauron's fancy-pants TPMS, complete with its butler service and cat paw massage facilities.

 

[SauRoNZA]

Aah yes, Sauron isn't going crazy, there are indeed some systems with pressure sensors inside the wheels: http://techcenter.mercedes-benz.com/en_ZA/tyre_pressure_monitoring/detail.html

Very spiffy.

Yeah my BMW has them.

But I checked the manual for the 3-series now and I do see they refer to it as TPMS in an explanation but actually all the feature you refer to FTM (Flat Tire Monitor) and it's a neat trick to use if you have ABS loaded anyway as it's just a bit of software really.

 

[SauRoNZA]

It doesn't tell pressure yes, just says one of the tyres has low pressure (can't say which one), or says a tyre is flat. The manual refers to it as TPMS as well as very other document I can find on the internet. That's why I also referred to it as TPMS.

Yeah I saw that in the manual now and I guess it's ultimately not really incorrect as it's not a trademarked system and the words do ring somewhat true that it is at least checking the overall system for pressure even though it's not accurately monitoring and displaying it.

Don't really need more than that on a car to be honest so it makes more sense as it's cheap (virtually free) and requires no replacement batteries and such.

But I do understand now why you would worry about the slime stuff affecting it but don't worry the ABS ring is still external to the tyre so it doesn't really matter at all what's inside each tyre as they'll still rotate the same as long as they are filled properly.

Interesting that it can't tell which one though as in reality it does have that information, but I guess it's not perfectly accurate.

 

[Foxhound5366]

But I checked the manual for the 3-series now and I do see they refer to it as TPMS in an explanation but actually all the feature you refer to FTM (Flat Tire Monitor) and it's a neat trick to use if you have ABS loaded anyway as it's just a bit of software really.

Haaibo, downgrading TPMS to FTM. What next? Degrading the 3 Series to a "petrol-driven variant of an oxcart"? Don't touch me on my TPMS, Sauron!