The official "my Yaris handles bad on the highway/with crosswinds" thread

[arcath]

why?

I was under the impression that 32 was stock. Hence my problem.

[blacksan]

Originally Posted by arcath

why?

I was under the impression that 32 was stock. Hence my problem.

If you over inflate without the factor of heavy load then you cause the tire to assume a more rounded, or U shaped profile. This causes less of a contact patch/profile in relationship to tire on the road surface. I am not an artist by any stretch of the imagination so try to imagine the difference between this ) (over inflation) and this ] (correct inflation) in relation ship to contact patch with road surface. Which would you consider more stable?

[grampi]

Originally Posted by blacksan

If you over inflate without the factor of heavy load then you cause the tire to assume a more rounded, or U shaped profile. This causes less of a contact patch/profile in relationship to tire on the road surface. I am not an artist by any stretch of the imagination so try to imagine the difference between this ) (over inflation) and this ] (correct inflation) in relation ship to contact patch with road surface. Which would you consider more stable?

Not true. As long as you stay under the max pressure listed on the sidewall, you'll suffer no ill-effects (with the exception of a stiffer ride, of course). Tires are made to hold their shape up to the max pressure regardless of vehicle weight. According to every tire expert I've talked to, running with the pressure listed on the driver's door plus 5 PSI is optimum for traction, handling, max tread life, and lowest road noise. The only benefit to running right at the recommended pressure is a smoother ride, but then everything else suffers.

[blacksan]

Originally Posted by grampi

Not true. As long as you stay under the max pressure listed on the sidewall, you'll suffer no ill-effects (with the exception of a stiffer ride, of course). Tires are made to hold their shape up to the max pressure regardless of vehicle weight. According to every tire expert I've talked to, running with the pressure listed on the driver's door plus 5 PSI is optimum for traction, handling, max tread life, and lowest road noise. The only benefit to running right at the recommended pressure is a smoother ride, but then everything else suffers.

http://www.thedieselstop.com/content...re%20Inflation

[nsmitchell]

Originally Posted by blacksan

http://www.thedieselstop.com/contents/getitems.php3?Proper%20Tire%20Inflation

Great article!

[blacksan]

Originally Posted by nsmitchell

Great article!

I didn't want to argue the fact, but I grew up in the heavy industry business and often pilot a vehicle up to and beyond 80K GVW. If I followed some of the advice given here I would have blown tires and killed myself, and or other innocent folks on the road.

[deebrown]

Originally Posted by blacksan

http://www.thedieselstop.com/content...re%20Inflation

no offense, but "the diesel stop" website looks pretty cheesy - like it was put together by some guy with Frontpage in his basement. Plus, and more importantly, the person who wrote the article doesn't list outside sources or detailed studies - seems like he's pretty much just giving his opinion...

[nsmitchell]

Originally Posted by deebrown

no offense, but "the diesel stop" website looks pretty cheesy - like it was put together by some guy with Frontpage in his basement. Plus, and more importantly, the person who wrote the article doesn't list outside sources or detailed studies - seems like he's pretty much just giving his opinion...

He does seem like he's giving just his knowledge, but it also jives with my understanding as well. My brother, who was a mechanic for 20+ years explained this stuff to me more than once. The chalk test is a surefire method to make sure your tires are correctly inflated. You can't really argue with his article. His website may look cheesy because this guy may primarily be a mechanic or an engineer.

[blacksan]

Originally Posted by nsmitchell

He does seem like he's giving just his knowledge, but it also jives with my understanding as well. My brother, who was a mechanic for 20+ years explained this stuff to me more than once. The chalk test is a surefire method to make sure your tires are correctly inflated. You can't really argue with his article. His website may look cheesy because this guy may primarily be a mechanic or an engineer.

+1 I have an engineering background and the article does a real good job of explaining things in a layman's terms. If he would have presented his thesis then no one would have been interested in reading it. I still get a kick out of folks that want to argue away things that they themselves are noy really shore about.

BTW, Have you ever been to the Harbour Freight store? I want to slip down there sometime soon and pick up a floor jack.

[deebrown]

Originally Posted by arcath

why?

I was under the impression that 32 was stock. Hence my problem.

My sedan tires do say 40 psi max but i found a link on the tire manufactures website that said 44 psi - i have since (for the last 6 weeks/2000 miles) been at 44 psi - I would say the improvement has been about 50%. I have looked at other message boards (including ones for the prius - which comes with the 185's on them as well) and it seems that upgrading to 195's makes a big difference (not sure if that's really true or not)...apparently, corrolla's also have this problem as well. i'm going to keep my current tires (like you, strapped for cash) until late November and then upgrade to 195's - as the 160 tread on those stock tires doesn't cut it in the wisconsin winters...