Harrier 2017

[richard_crl032]

  On 1/7/2018 at 2:03 AM, Davidtch said:

Look at the load index of factory spec tyre vs tyre on car.

 

May need to increase or decrease tyre pressure

Hi David,

 

Kindly elaborate or share link on load index and how to go about making deviation from recommended tyre pressure.

 

Thanks in advance.

 

Cheers.

 

Richard

[inlinesix]

  On 1/7/2018 at 2:08 AM, richard_crl032 said:

Hi David,

 

Kindly elaborate or share link on load index and how to go about making deviation from recommended tyre pressure.

 

Thanks in advance.

 

Cheers.

 

Richard

In tyre section, there is 1 thread on load index and another thread on load index

 

Download conti tyre brochure which has a table on load index + tyre pressure => corresponding weight

 

Use that table to find corresponding pressure once load index differs from factory.

 

Factory tyre pressure is minimum.

[explorerX]

  On 1/6/2018 at 11:05 PM, richard_crl032 said:

For petrol station pump, you should pump up to additional 10-15kpa to recommended tyre pressure on label without any loaded passengers since tyres are already heated up and loaded tyres will show higher pressures... if you have installed tpms, you will then notice tyres pressure nearer to the recommended tyre pressure in the morning after left overnite and it is ok to be higher after running around especially during hot noon.

 

Cheers.

 

Richard

 

Hi Richard, thanks for the tip. 

[The_mark]

  On 1/6/2018 at 4:23 PM, explorerX said:

Not for harrier :(

 

210 not under inflated? My previous ride 17" I am on 230F/220R & much lighter car than HT.

Oh, interesting. For my previous car on 15", it was about 210. My 18" now states 240 to 270 depending of car typical loading. I pump 270.

 

There's 2 sets of numbers for my car too, for 18" and 17" because stock comes either with 17 or 18. Is your 18" factory default or changed locally by BM?

Edited January 7, 2018 by The_mark

[explorerX]

  On 1/7/2018 at 3:12 AM, The_mark said:

Oh, interesting. For my previous car on 15", it was about 210. My 18" now states 240 to 270 depending of car typical loading. I pump 270.

 

There's 2 sets of numbers for my car too, for 18" and 17" because stock comes either with 17 or 18. Is your 18" factory default or changed locally by BM?

 

Rims are factory default, same set are shown on JDM models brochure.

 

Tire pressure does affects the ride experience, over inflate jumpy, under inflate slower pickup.

All my previous rides are higher for front due to the engine's weight, for HT it's the 1st time I come across 220 for 4pcs & 1.7 ton car. Will try and error till I get the sweet spot, just done my 1k oil change. Need to spend more mileage with this new " gf " to get connection LOL. 

[The_mark]

  On 1/7/2018 at 3:54 AM, explorerX said:

Rims are factory default, same set are shown on JDM models brochure.

 

Tire pressure does affects the ride experience, over inflate jumpy, under inflate slower pickup.

All my previous rides are higher for front due to the engine's weight, for HT it's the 1st time I come across 220 for 4pcs & 1.7 ton car. Will try and error till I get the sweet spot, just done my 1k oil change. Need to spend more mileage with this new " gf " to get connection LOL.

Agreed that for such a heavy car, 220 sounds really low. I would reckon min 240.

 

Enjoy your intimate connection with your "gf" to find that sweet spot.

[Thaiyotakamli]

  On 1/6/2018 at 11:05 PM, richard_crl032 said:

Hi Thai,

 

Recommended tyre pressures on car label refers to cold tyres in the case when you are at tyres shop for new ones.

 

For petrol station pump, you should pump up to additional 10-15kpa to recommended tyre pressure on label without any loaded passengers since tyres are already heated up and loaded tyres will show higher pressures... if you have installed tpms, you will then notice tyres pressure nearer to the recommended tyre pressure in the morning after left overnite and it is ok to be higher after running around especially during hot noon.

 

As a result of above overlooked points, we tend to under-inflate our tyres and have prematured tyre wear on outside of tyres in additional to more noisy ride, poorer FC and longer braking distance than intended.

 

Especially for long distance nshwy driving, it is more important to get tyre pressure correct and not under inflated.

 

Cheers.

 

Richard

Hi Richard

 

Normally i pump at midnight and from my house to petrol station few hundred metre only i think when i pump the tyre still cool. i nvr install tpms. i think overinflate lead to more tyre noise imo and going through bump or pothole lagi worse. just my observation tho

 

 

regard

thai

[andrewyewkc]

  On 1/6/2018 at 2:11 PM, explorerX said:

Owners, can share whats the tire pressure settings u guys use?

 

Manual states 220 which I find it puzzling for 18".

Let me hazard a guess. The sweet spot is probably around 230 kPa for such a heavy car. 220 is ok but 210 is probably too low. I usually inflate slightly higher to 255 kPa. When my ride start to get more comfortable, it means my pressure has dropped and I will pump again. I sacrifice some comfort for improved handling, fuel efficiency, tire wear rate and convenience as this gives me more time before I need to reinflate the tires. Actually trial and error is the best way to find the best pressure instead of manufacturer's recommendation, so just vary your tyre pressure and feel the difference to find the pressure that suits you the best.

[inlinesix]

  On 1/8/2018 at 3:09 AM, andrewyewkc said:

Let me hazard a guess. The sweet spot is probably around 230 kPa for such a heavy car. 220 is ok but 210 is probably too low. I usually inflate slightly higher to 255 kPa. When my ride start to get more comfortable, it means my pressure has dropped and I will pump again. I sacrifice some comfort for improved handling, fuel efficiency, tire wear rate and convenience as this gives me more time before I need to reinflate the tires. Actually trial and error is the best way to find the best pressure instead of manufacturer's recommendation, so just vary your tyre pressure and feel the difference to find the pressure that suits you the best.

Manufacturer recommendation is the minimum pressure. One should not pump lower than that as car tyre is load bearing.

 

Pump higher does not improve handling. Higher pressure will reduce tyre contact patch

[andrewyewkc]

  On 1/8/2018 at 8:32 AM, Davidtch said:

Manufacturer recommendation is the minimum pressure. One should not pump lower than that as car tyre is load bearing.

 

Pump higher does not improve handling. Higher pressure will reduce tyre contact patch

Agree, reduced pressure will increase the contact patch and reducing the pressure by 20% less than prescribed will actually have the shortest braking distance.

 

http://article.sapub.org/10.5923.j.ijtte.20130202.01.html

 

"The vehicle had the shortest braking distance when the tires have been inflated 20% less than the prescribed pressure.The vehicle was losing its stability when braking at slow velocity and even on flat surface."

Edited January 9, 2018 by andrewyewkc

[richard_crl032]

  On 1/9/2018 at 2:16 AM, andrewyewkc said:

Agree, reduced pressure will increase the contact patch and reducing the pressure by 20% less than prescribed will actually have the shortest braking distance.

 

http://article.sapub.org/10.5923.j.ijtte.20130202.01.html

 

"The vehicle had the shortest braking distance when the tires have been inflated 20% less than the prescribed pressure.The vehicle was losing its stability when braking at slow velocity and even on flat surface."

Hi Andrew,

 

Great read and I had learned.

 

What do you make out of the below in final paragraph on wet condition?

 

Poorly inflated tires worse reacts to the action of lateral forces, resulting in a significantly worse driving and also has the wet braking distance than in the case of a dry surface. The results of measuring the stopping distance and braking adverse effects the drive-ability of the vehicle clearly show that in terms of safety is the manufacturer specified tire inflation optimum.

 

Cheers.

 

Richard

[andrewyewkc]

  On 1/9/2018 at 5:05 AM, richard_crl032 said:

What do you make out of the below in final paragraph on wet condition?

 

Poorly inflated tires worse reacts to the action of lateral forces, resulting in a significantly worse driving and also has the wet braking distance than in the case of a dry surface. The results of measuring the stopping distance and braking adverse effects the drive-ability of the vehicle clearly show that in terms of safety is the manufacturer specified tire inflation optimum.

 

The English not so good but I think the effect of a poorly inflated tire is worse under wet road conditions. Lower pressure affects handling and control. Generally the most conservative approach is to follow manufacturer specification for optimal safety.

[richard_crl032]

  On 1/9/2018 at 6:38 AM, andrewyewkc said:

The English not so good but I think the effect of a poorly inflated tire is worse under wet road conditions. Lower pressure affects handling and control. Generally the most conservative approach is to follow manufacturer specification for optimal safety.

Hi Andrew,

 

Thanks and indeed a bit singlish but I also concluded the same that indeed under inflated tyres has reduced braking in dry conditions but worse under wet road conditions .. with recommended mfgrs tyre pressure being the optimum.

 

Cheers.

 

Richard

[andrewyewkc]

  On 1/9/2018 at 11:33 PM, richard_crl032 said:

Hi Andrew,

 

Thanks and indeed a bit singlish but I also concluded the same that indeed under inflated tyres has reduced braking in dry conditions but worse under wet road conditions .. with recommended mfgrs tyre pressure being the optimum.

 

Cheers.

 

Richard

It is optimal for safety and comfort only.

[richard_crl032]

  On 1/10/2018 at 3:20 AM, andrewyewkc said:

It is optimal for safety and comfort only.

Hi Andrew,

 

Dun mean to patronise but ONLY seems to infer other consideration(s) over safety and comfort by complying to recommended mfgr recommended tyre pressure if we accept the conclusion from this article ??

 

Cheers.

Edited January 11, 2018 by richard_crl032

[andrewyewkc]

  On 1/11/2018 at 12:10 AM, richard_crl032 said:

Hi Andrew,

 

Dun mean to patronise but ONLY seems to infer other consideration(s) over safety and comfort by complying to recommended mfgr recommended tyre pressure if we accept the conclusion from this article ??

 

Cheers.

Hi Richard,

 

I will try to understand and answer your question. As I mentioned in my earlier post, other considerations that I value are:

fuel efficiency, handling, tire wear rate and convenience. Some people may also increase the pressure if they have bigger rims.

 

Safety wise I feel that the brake and reaction time affect braking distance much more than just tire pressure. Comfort wise, it is a tradeoff, that is why I say trial and error to see how much beating the butt can take. I prefer my tires harder if possible. Haha, sorry, I think I am making something simple complicated.

[richard_crl032]

  On 1/11/2018 at 3:40 AM, andrewyewkc said:

Hi Richard,

 

I will try to understand and answer your question. As I mentioned in my earlier post, other considerations that I value are:

fuel efficiency, handling, tire wear rate and convenience. Some people may also increase the pressure if they have bigger rims.

 

Safety wise I feel that the brake and reaction time affect braking distance much more than just tire pressure. Comfort wise, it is a tradeoff, that is why I say trial and error to see how much beating the butt can take. I prefer my tires harder if possible. Haha, sorry, I think I am making something simple complicated.

Hi Andrew,

 

Understand fully and tks tks !

 

Richard

[richard_crl032]

Ummh .... quite almost 2 weeks lapse without new post. 

 

Harrier turbo owners are really likened to be aspiring or just made-it towkays and not the usual forum sharing type or enjoying so much of their new ride to be too busy to share or nothing more to share since perfect liao ? 

 

Cheers,