Bigger Tyres

[pod10811]

Hi everyone,

First post on this forum hope you can help.

I've got a Yaris 1.0vvti, I decided to changes the tyres and go wider on the existing rims, therefore I went from 155/80 -13 to 175/70 -13 which are the nearest to maintain circumference.

The problem is the steering has now gone very light, in corners it feels as though it is understeering, although it's not, centering force on the wheel has got a lot less as well, sometimes it feels like the car wants to turn into a corner by it's self.

All in all not confidence inspiring.

Tyre pressures are correct for the new size as per toyota's recommendation.

What do you think is happening. ?

Thanks for the help in advance.

[gar]

Hi everyone,

First post on this forum hope you can help.

I've got a Yaris 1.0vvti, I decided to changes the tyres and go wider on the existing rims, therefore I went from 155/80 -13 to 175/70 -13 which are the nearest to maintain circumference.

The problem is the steering has now gone very light, in corners it feels as though it is understeering, although it's not, centering force on the wheel has got a lot less as well, sometimes it feels like the car wants to turn into a corner by it's self.

All in all not confidence inspiring.

Tyre pressures are correct for the new size as per toyota's recommendation.

What do you think is happening. ?

Thanks for the help in advance.

Check the tyres rotational direction is facing the correct way.

[forde]

centering force would have lessened because the new tyres are heavier probably.

maybe theyre just crap tyres lol wat make are they

[pod10811]

centering force would have lessened because the new tyres are heavier probably.

maybe theyre just crap tyres lol wat make are they

I had thought about the crap tyres option !! and yes they are some weird foreign brand, and they were very cheap £ 125 inc fitting for four.

Anybody got any thoughts about varying tyre pressures, what do you all think about the max pressure -10% method.

I will check the direction of rotation, but I can't remember seeing any marks or arrows for this.

[gar]

centering force would have lessened because the new tyres are heavier probably.

maybe theyre just crap tyres lol wat make are they

I had thought about the crap tyres option !! and yes they are some weird foreign brand, and they were very cheap £ 125 inc fitting for four.

Anybody got any thoughts about varying tyre pressures, what do you all think about the max pressure -10% method.

I will check the direction of rotation, but I can't remember seeing any marks or arrows for this.

Just read a piece about fitting bigger tyres. It said roadholding can worsen, especially in wet/frosty/snowy weather! I know from years ago, fitting wider tyres and low profile stuff can make the stearing heavier and wear out the tyres faster but you seem to have only gone about the size of the higher spec Yaris', I think!

I would have thouth it was either rubbish tyres or poor fitting.

What brand were they after all?

[pod10811]

centering force would have lessened because the new tyres are heavier probably.

maybe theyre just crap tyres lol wat make are they

I had thought about the crap tyres option !! and yes they are some weird foreign brand, and they were very cheap £ 125 inc fitting for four.

Anybody got any thoughts about varying tyre pressures, what do you all think about the max pressure -10% method.

I will check the direction of rotation, but I can't remember seeing any marks or arrows for this.

Just read a piece about fitting bigger tyres. It said roadholding can worsen, especially in wet/frosty/snowy weather! I know from years ago, fitting wider tyres and low profile stuff can make the stearing heavier and wear out the tyres faster but you seem to have only gone about the size of the higher spec Yaris', I think!

I would have thouth it was either rubbish tyres or poor fitting.

What brand were they after all?

[pod10811]

centering force would have lessened because the new tyres are heavier probably.

maybe theyre just crap tyres lol wat make are they

I had thought about the crap tyres option !! and yes they are some weird foreign brand, and they were very cheap £ 125 inc fitting for four.

Anybody got any thoughts about varying tyre pressures, what do you all think about the max pressure -10% method.

I will check the direction of rotation, but I can't remember seeing any marks or arrows for this.

Just read a piece about fitting bigger tyres. It said roadholding can worsen, especially in wet/frosty/snowy weather! I know from years ago, fitting wider tyres and low profile stuff can make the stearing heavier and wear out the tyres faster but you seem to have only gone about the size of the higher spec Yaris', I think!

I would have thouth it was either rubbish tyres or poor fitting.

What brand were they after all?

The brand is Mohawk.

I suppose I will have to go careful until they wear out and then go back to where I was before size wise, you're right though a 175 is standard fit but that is on a 14" rim so the aspect ratio is lower, perhaps that makes a difference.