What is tyre flex?

[Izso]

After changing to these new tyres Yokohama Cdrive2 195/55/15 and adjustables, I've been experiencing something I've never come across before. I can't figure out if it's tyre flexing or the antiroll bar is not stiff enough.

Situation : hard (and sometimes fast) directional changes from left to right will result in the car suddenly squatting on the bottom left side which suddenly forces the turns even more which makes it somewhat unpredictable.

I stiffened the suspension to compensate and reduce body roll however I needed some body roll to some extent and that squat is still noticeable.

Is this the rear antiroll-bar sinking or being too soft or is this the tyre flexing around?

 

[johnsonlam]

"Squat" as in the weight is shifted to that part of the car?

From the sound of it, the spring rate for the Adjustable arent quite right for your car.

To rule out the Tire as the issue, try a few laps in the neighbourhood with your tires pumped up to higher pressure... 35PSI just to test it.

 

[^pomen_GTR^]

what was your previous tyre size and type?

if prev was 195/50-15 i believe it was tyre flex.....since thicker sidewalls=easier to flex wall...

 

[Izso]

"Squat" as in the weight is shifted to that part of the car?

From the sound of it, the spring rate for the Adjustable arent quite right for your car.

To rule out the Tire as the issue, try a few laps in the neighbourhood with your tires pumped up to higher pressure... 35PSI just to test it.

Yeah, weight shift. I can feel the weight shift which in turn pushes the car more into the corner. I haven't been able to properly control this which is why I want to get rid of it. Makes cornering fast very difficult and unpredictable.

Spring rate is the stock 6k front 4k rear. Any stiffer and the car will bounce around a lot. I've used 8k front and 6k rear before and that was unbearably uncomfortable.

My tyre pressure is normally at 240kpa which is about 35psi already.

what was your previous tyre size and type?

if prev was 195/50-15 i believe it was tyre flex.....since thicker sidewalls=easier to flex wall...

Erm... my previous tyre was 205/45/16. No flex confirm! But these tyres supposed to have relatively stiff sidewalls. Not like the hankooks

 

[vr2turbo]

Yeah, weight shift. I can feel the weight shift which in turn pushes the car more into the corner. I haven't been able to properly control this which is why I want to get rid of it. Makes cornering fast very difficult and unpredictable.

Spring rate is the stock 6k front 4k rear. Any stiffer and the car will bounce around a lot. I've used 8k front and 6k rear before and that was unbearably uncomfortable.

My tyre pressure is normally at 240kpa which is about 35psi already.




Erm... my previous tyre was 205/45/16. No flex confirm! But these tyres supposed to have relatively stiff sidewalls. Not like the hankooks

If you had no problem with 205/45R16 on same setup then the tyre are flexing too much. Try up to 40psi for those super soft sidewall Yokies CD2 and see how it goes.
But having more air in soft sidewall tyres are no fun. I rather have normal air pressure on hard sidewall tyres. Tested them before in the Toyo T1-R in my VR. To me this tyre sidewall too soft also...

 

[^pomen_GTR^]

sounds like confirm is flexing sidewall to me...

unless your tyre is those semislick with hard sidewall then still complains maybe its due to something else.....

 

[vr2turbo]

Izso, come switch my 17" GT Radial HPY and try. If still flex then suspension or ARB problem....

 

[Izso]

Izso, come switch my 17" GT Radial HPY and try. If still flex then suspension or ARB problem....

ok When?

 

[vr2turbo]

ok When?

Anytime you are free give me a call.
My rims are 8 holes so no worry, direct swap. Only you will need more juice to start up as overall diameter is 5% bigger, but then testing suspension only.

Okay, give you choice, my Hyundai also 17" on Goodyear Asy 2, rims also 8 holes.....ha! ha!
But HPY have harden sidewall....

 

[Supra_Fanatics]

can my corolla try too?

 

[^pomen_GTR^]

if put on my daily satria confirm have to put the "O/D off" mode most of the time

 

[vr2turbo]

can my corolla try too?

Come, come. Got two sets mah!

 

[Supra_Fanatics]

Come, come. Got two sets mah!

So is a 17" DIT.

 

[vr2turbo]

So is a 17" DIT.

Need more jacks.....

 

[Supra_Fanatics]

Need more jacks.....

Ask Izso to bring along hehe