Jump to content

  •  

Show
Photo
- - - - -

Tire Pressures?


  • Please log in to reply
29 replies to this topic

#1 ItalianStig

ItalianStig

    Club Member

  • Registered Member
  • PipPip
  • 50 posts
  • Gender*:Male
  • Toyota Model: 2001 Yaris vvti

Posted 03 March 2011 - 09:46 PM

hey guys, just wondering what the tyre front and rear tires pressures should be for my 2001 yaris vvti?

cheers

Have something to contribute?

Sign in or register to start a topic...

Sign up to TOC Premium Membership To Remove These Ads

#2 Cyker

Cyker

    Top Rank Poster!

  • Registered Member
  • PipPipPipPipPipPipPipPip
  • 2,997 posts
  • Gender*:Male
  • Toyota Model: Yaris/03

Posted 03 March 2011 - 11:24 PM

It's in the manual, or on the edge of the door IIRC

It was something like 35/32 IIRC (I run 40/35 for fuel efficiency tho' :))

#3 Hartside

Hartside

    Advanced Club Member

  • Registered Member
  • PipPipPipPip
  • 165 posts
  • First Name:Colin
  • Gender*:Male
  • Toyota Model: Yaris 1.3TR
  • Year: 2008
  • Location: Northumberland

Posted 04 March 2011 - 12:03 AM

(I run 40/35 for fuel efficiency tho'



That might give you better fuel efficiency, but it will lead to premature tyre wear in the centre and also reduce your braking effiency as you are reducing the contact patch presented to the road by over inflating. It could be quite dangerous in the wet. What's wrong with the manufacturers recommended pressures?

#4 Cyker

Cyker

    Top Rank Poster!

  • Registered Member
  • PipPipPipPipPipPipPipPip
  • 2,997 posts
  • Gender*:Male
  • Toyota Model: Yaris/03

Posted 04 March 2011 - 01:10 AM

They say overpressure will lead to premature wear in the centre but I haven't found that at all.

The theory for premature centre wear is that the tyre bulges out in the middle when you over inflate it, but I reckon you'd have to go over the recommended spec by considerably more than 5psi for that to happen.

I've been running that setup for a while now, and if anything the tyre wear has been a lot more even; At the recommended pressures I was getting noticeably more wear on the outer edges of the tyre compared to now.

Hasn't affected braking or acceleration negatively that I've noticed (If anything they've been sharper!) and you can 'feel' the car better at motorway speeds.

The only nasty detriment of the higher pressures that I've found is that the car is noticeably more understeery in the wet, especially on loose surfaces, but that might be partly down to the fact that they need changing (Nearing 3mm; I generally replace them round there rather than waiting until they drop to the legal minimum!).

(When I say it's more understeery, this is when I'm thrashing it down some open country road BTW; Under normal driving conditions I'd never get near the tyre's grip limit no matter what pressure it's at! :lol:)


But it is worth mentioning these things; Over inflating changes the behaviour of the car and tyre, and it's a lot like a 1st generation low rolling resistance tyre.

And deffo go back to stock pressures in the snow!


I'm going to be getting some ContiEcoContact 3's soon... still debating whether to go high-pressure with those or not!

#5 Korny_Yaris

Korny_Yaris

    Advanced Club Member

  • Registered Member
  • PipPipPipPip
  • 172 posts
  • First Name:Mark
  • Gender*:Male
  • Toyota Model: Corolla T Sport
  • Year: 2005
  • Location: Derbyshire

Posted 04 March 2011 - 12:04 PM

just go here mate, bang in ur license plate number, job done. :thumbsup:

http://www.kwik-fit....sure-search.asp

#6 GS John

GS John

    Club Member

  • Registered Member
  • PipPip
  • 93 posts
  • Gender*:Male
  • Toyota Model: 2010 1.33 Yaris T Spirit, 2004 1.3 Yaris
  • Location: Aberdeenshire

Posted 05 March 2011 - 10:51 AM

It was something like 35/32 IIRC (I run 40/35 for fuel efficiency tho' :))


Have you read the Highway Coode recently, or Law CUR reg 27?

Also here if you haven't: http://www.direct.go...ycode/DG_069871 :thumbsup:

#7 carlowlad

carlowlad

    Advanced Club Member

  • Registered Member
  • PipPipPipPip
  • 127 posts
  • Gender*:Male
  • Toyota Model: yaris 1.4D4D
  • Location: ---------Ireland-----------

Posted 05 March 2011 - 10:03 PM

They say overpressure will lead to premature wear in the centre but I haven't found that at all.....................................................................

And deffo go back to stock pressures in the snow!


I'm going to be getting some ContiEcoContact 3's soon... still debating whether to go high-pressure with those or not!

+1

Mind you, if overinflated from new they will wear in the centre. Leave them at the recommended pressure for say 1000miles then bump up the pressure. I've done this and all was ok. Apparently when the wire beds in it will stay that way. so from new it will bed in in a bulge if overinflated. But leave the pressure down and it will bed in evenly. Then overinflate as much as you dare... High pressures from new had my tyres wearing more in the middle, despite lowering the pressure to even it out. That uneven-ness stayed there.

Re; the regs on tyre presure. Thats interesting alright. However, there is NO evidence ANYWHERE that i can find that shows how grip decreases at higher tyre pressures. Believe me, i've looked. By all means show me though.
Let me know how the conti eco contact tyres go for you. I was thinking along these lines:http://www.tyrereviews.co.uk/Tyre/Toyo/350.htm
http://www.ctyres.co...s/Toyo/350.html
Thoughts?

#8 Cyker

Cyker

    Top Rank Poster!

  • Registered Member
  • PipPipPipPipPipPipPipPip
  • 2,997 posts
  • Gender*:Male
  • Toyota Model: Yaris/03

Posted 05 March 2011 - 10:52 PM

Thanks for the tip :)

I guess I'll run them at stock to see how they feel and then experiment with the higher pressures later :)

I think that as the tyre compound is harder, it might not deform as much under load vs normal tyres and thus not benefit so much from the higher pressures.

The other thing is as it naturally has less grip than a normal tyre, it might actually be much worse so I guess it'll be a case of experimentation :)

#9 markweatherill

markweatherill

    Club Member

  • Registered Member
  • PipPip
  • 62 posts
  • Gender*:Male
  • Toyota Model: WiLL Vi

Posted 05 March 2011 - 11:12 PM

That old warning about overinflated tyres wearing out the centre of the tread is from the olden days of cross-ply tyres, by the way.
I haven't heard of brand new (radial) tyres developing a bulge if overinflated, and I've not experienced that. (If they're on the car, the tread would be flattening against the road surface all round the tyre circumference, all the time the wheels were going round anyway which would counteract any tendency to bulge, even if the tyre construction allowed it to happen)
This thread reminds me to check my tyre pressures tomorrow. Thanks!

#10 Hartside

Hartside

    Advanced Club Member

  • Registered Member
  • PipPipPipPip
  • 165 posts
  • First Name:Colin
  • Gender*:Male
  • Toyota Model: Yaris 1.3TR
  • Year: 2008
  • Location: Northumberland

Posted 06 March 2011 - 11:16 AM

Wow, I can't believe what I'm reading - you guys are worrying me!

http://www.theaa.com...-pressures.html

http://www.michelin....f-tyre-problems

http://www.kwik-fit....re-pressure.asp

http://www.safermoto...rePressure.html

All the above make reference to over inflation as well as under inflation.

Have something to contribute?

Sign in or register to start a topic...


Not what you're looking for?

Register now, we have a huge community of enthusiasts to answer any questions you might have



0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users