High speed driving/ tyre life - Team-BHP

rks · 22nd November 2005, 19:37

Folks,
I have just joined the forum and hope to get some important info from the various experts.

I drive an old Santro (Oct 2000 model, 1-lit). The car has done about 18500 kms in 5years, mostly in good road conditions. Recently, after my shift to Pune from Bangalore, I find myself doing the Pune-Mumbai route via the expressway quite frequently. I am prone to speeding and quite often push the Santro to its top speed (145-150 kph, speedo reading); I am consistently at speeds in excess of 130 kph on the expressway. I recently became aware of the dangers of tyre blowouts at such speeds, and so have the following questions on tyre maintenance.

(1) The tyres right now appear to be in excellent condition (treads, sidewalls), but they are already 5 years old. Is it necessary to go in for a tyre change, despite the low mileage of 18500 kms? If so, what tyres do you recommend for a safe drive at high speeds? Is it advisable to go in for tubeless tyres? I read on this forum that one problem with these is that small puncture shops don't know how to handle tubeless tyres and may end up damaging them.

(2) I check the tyre pressures at a Pune BP bunk before leaving for Mumbai, and set them to 30 psi in cold condition. But when I check the tyre pressures (cold) at the Mumbai bunk, they always complain that the tyres are over-inflated, to about 36 psi !!! So obviously I need to get a good pressure gauge; which one do you recommend, and how do I ensure that the gauge is correct (i.e, I assume that the gauge has to be calibrated from time to time; where do I get this done?).

(3) The tyres (Bridgestone S322) are S-rated, which can supposedly handle 180 kph (for how long, continuously?). However, I am extremely worried about the fact that the roads in Pune (where I live) are horrible in the monsoon season, with serious pot-holes/sharp stones, etc. So how will that affect the speed rating of the tyres? i.e., should I worry about any weak spots developing on the tyres/tubes which will come back to haunt me while I zip through the expressway?

Contrary to what I have often read in various forums, I find that my old Santro handles the high speeds quite brilliantly (although it could obviously do with more power/pick-up). The only dangers I have encountered on the expressway are:

(a) Objects, including road-blocks, stones, etc. on the right/left lanes, obviously left by workers who maintain the roads/dividers; these are a serious menace at night.

(b) Slow-moving vehicles, which often hog the right lane and force fast-moving vehicles to frequently change lanes. It seems that many people take the absurd speed limits of 80 kph, 50 kph and even 30 kph (!!!!) at various locations on the expressway too seriously. Especially at night, people who go at extremely slow speeds are a menace for the fast-moving vehicles because you may be on their tails before you even realize it (I myself had to do rapid lane changes on a couple of occasions at night, once when a car on the right lane seemed to be going at snail's pace, almost stopped).

(c) On one occasion, I found a big truck on the right lane coming in the opposite direction at night, and had to shift to the middle lane. Horror of horrors. I rubbed my eyes in disbelief and was even momentarily confused on whether I myself got into the wrong side of the expressway. Obviously the driver was either drunk or made a serious error (or was he trying to pull a smart-aleck stunt to avoid paying toll?).

Regards, rks

Shan2nu · 22nd November 2005, 19:55

Quote:

(1) The tyres right now appear to be in excellent condition (treads, sidewalls), but they are already 5 years old. Is it necessary to go in for a tyre change, despite the low mileage of 18500 kms? If so, what tyres do you recommend for a safe drive at high speeds? Is it advisable to go in for tubeless tyres? I read on this forum that one problem with these is that small puncture shops don't know how to handle tubeless tyres and may end up damaging them.

I think one should change tyres, once every 4-5 years. Even if the tyres have considerable tread on them, the rubber compound would have bcome hard and lost it's ability to grip.

Go in for tubeless tyres. They're a lot safer and puncture resistant than tubed tyres.

Quote:

(2) I check the tyre pressures at a Pune BP bunk before leaving for Mumbai, and set them to 30 psi in cold condition. But when I check the tyre pressures (cold) at the Mumbai bunk, they always complain that the tyres are over-inflated, to about 36 psi !!! So obviously I need to get a good pressure gauge; which one do you recommend, and how do I ensure that the gauge is correct (i.e, I assume that the gauge has to be calibrated from time to time; where do I get this done?).

There's nothing wrong with their gauge, the increase in pressure is bcoz the tyres heat up (due to friction) when they're are run at high speeds which makes the air inside expand with heat.

Don't check your tyres pressure as soon as you reach B'bay. Give the tyre some time to cool down (4 hours should be more than enuf). But remember, the car shouldn't be driven for those 4 hours or else the heat will build up again.

Do get yourself a good gauge anyway, it's much safer.

Quote:

(3) The tyres (Bridgestone S322) are S-rated, which can supposedly handle 180 kph (for how long, continuously?). However, I am extremely worried about the fact that the roads in Pune (where I live) are horrible in the monsoon season, with serious pot-holes/sharp stones, etc. So how will that affect the speed rating of the tyres? i.e., should I worry about any weak spots developing on the tyres/tubes which will come back to haunt me while I zip through the expressway?

According to standards, an S rated tyre should be able to handle 180kmph for a period of one hour without any problems but...........those are under ideal testing conditions. For normal use, always buy tyres that can handle 20-30kmph more than the top speed of your vehicle. This will put less strain on the tyre and let you enjoy your vehicle at full whack.

I've got a Vtec, which is rated at 185kmph (true speed) and i've got H rated tyres, that can handle speeds of upto 210kmph.

Shan2nu

Rudra Sen · 22nd November 2005, 20:09

rks, This is not a post of introduction.
Please go through the announcement section. Go through all the topic heads. Post in the right section for right information.

We're closing this thread and waiting to see your introduction as new thread. Thanks.

22nd November 2005, 19:37	#1 (permalink)
rks BANNED Join Date: Nov 2005 Location: ?? Posts: 1,198	High speed driving/ tyre life Folks, I have just joined the forum and hope to get some important info from the various experts. I drive an old Santro (Oct 2000 model, 1-lit). The car has done about 18500 kms in 5years, mostly in good road conditions. Recently, after my shift to Pune from Bangalore, I find myself doing the Pune-Mumbai route via the expressway quite frequently. I am prone to speeding and quite often push the Santro to its top speed (145-150 kph, speedo reading); I am consistently at speeds in excess of 130 kph on the expressway. I recently became aware of the dangers of tyre blowouts at such speeds, and so have the following questions on tyre maintenance. (1) The tyres right now appear to be in excellent condition (treads, sidewalls), but they are already 5 years old. Is it necessary to go in for a tyre change, despite the low mileage of 18500 kms? If so, what tyres do you recommend for a safe drive at high speeds? Is it advisable to go in for tubeless tyres? I read on this forum that one problem with these is that small puncture shops don't know how to handle tubeless tyres and may end up damaging them. (2) I check the tyre pressures at a Pune BP bunk before leaving for Mumbai, and set them to 30 psi in cold condition. But when I check the tyre pressures (cold) at the Mumbai bunk, they always complain that the tyres are over-inflated, to about 36 psi !!! So obviously I need to get a good pressure gauge; which one do you recommend, and how do I ensure that the gauge is correct (i.e, I assume that the gauge has to be calibrated from time to time; where do I get this done?). (3) The tyres (Bridgestone S322) are S-rated, which can supposedly handle 180 kph (for how long, continuously?). However, I am extremely worried about the fact that the roads in Pune (where I live) are horrible in the monsoon season, with serious pot-holes/sharp stones, etc. So how will that affect the speed rating of the tyres? i.e., should I worry about any weak spots developing on the tyres/tubes which will come back to haunt me while I zip through the expressway? Contrary to what I have often read in various forums, I find that my old Santro handles the high speeds quite brilliantly (although it could obviously do with more power/pick-up). The only dangers I have encountered on the expressway are: (a) Objects, including road-blocks, stones, etc. on the right/left lanes, obviously left by workers who maintain the roads/dividers; these are a serious menace at night. (b) Slow-moving vehicles, which often hog the right lane and force fast-moving vehicles to frequently change lanes. It seems that many people take the absurd speed limits of 80 kph, 50 kph and even 30 kph (!!!!) at various locations on the expressway too seriously. Especially at night, people who go at extremely slow speeds are a menace for the fast-moving vehicles because you may be on their tails before you even realize it (I myself had to do rapid lane changes on a couple of occasions at night, once when a car on the right lane seemed to be going at snail's pace, almost stopped). (c) On one occasion, I found a big truck on the right lane coming in the opposite direction at night, and had to shift to the middle lane. Horror of horrors. I rubbed my eyes in disbelief and was even momentarily confused on whether I myself got into the wrong side of the expressway. Obviously the driver was either drunk or made a serious error (or was he trying to pull a smart-aleck stunt to avoid paying toll?). Regards, rks

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22nd November 2005, 20:09	#3 (permalink)
Rudra Sen Team-BHP Support Join Date: Apr 2004 Location: Bangalore Posts: 3,961 View My Garage	rks, This is not a post of introduction. Please go through the announcement section. Go through all the topic heads. Post in the right section for right information. We're closing this thread and waiting to see your introduction as new thread. Thanks.