[HELP] Iriz Rear End Hopping

DNGFashion

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DNGFashion

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Hi all sifus,

Currently, while I take corners (medium long / long corners) on uneven pavement or motorway with expansion joints or mild uneven surface at 50km/h or less, the rear end will skip or hop. Also I neither accelerate nor brake during cornering.

I have looked up on cars with torsion beam suspension. Some of them experienced such complications while others are close to none. Also, there are no concrete direct solutions which can curb this problem.

Any recommendations or advice please?

Thank you.
 

gunnerzz

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gunnerzz

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Check your rear tyre pressure.

If its really hopping then the vsc light should blink.does it blink?
Some bridge joint or road joint are metal and your tyre wont have much grip.but in this case it will slide a bit,nothing dramatic.
the stock tyre is crappy.
 

DNGFashion

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DNGFashion

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Some expansion joint is overlay with concrete.
Nope the VSC light didn't blink.

So to change tyre and suspension?
 

gunnerzz

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gunnerzz

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dont change the tyre if its really hopping as its due to either the an overinflate tyre or suspension or you are going too fast for the corner.
i have never experience hopping before or normal driviing speed.however,the rear suspension can easily be upset when you are driving alone with the rear tyre inflated to the higher recommended pressure to carry people.
fast definition really depends to individual.my fast could be slow for you.

The cheapest solution is to recheck the tyre pressure and adapt your driving style to the car character.
 

DNGFashion

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DNGFashion

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Front 32 psi and rear 30psi, driving alone all the time.
My normal cornering speed is equal or less than 40km/h on medium long or long corners. If sharp turns, it will be definitely lower than 10km/h. Cornering wouldn't be fun anymore :(

I try lowering the tyre pressure
 

vr2turbo

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vr2turbo

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can it be done on my own? or I need to consult a mechanic for such service?
Normally they press hard on your car and see the re bounce. If car keep bouncing up and down means worn. If jam then hard to even press down. Best if can find suspension test machine. Some tyre shops used to have, but lately cannot find any. Car driven over a platform, the machine bounces the tyre up and down then record the feedback.....:smokin:
 

^pomen_GTR^

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^pomen_GTR^

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Hi all sifus,

Currently, while I take corners (medium long / long corners) on uneven pavement or motorway with expansion joints or mild uneven surface at 50km/h or less, the rear end will skip or hop. Also I neither accelerate nor brake during cornering.

I have looked up on cars with torsion beam suspension. Some of them experienced such complications while others are close to none. Also, there are no concrete direct solutions which can curb this problem.

Any recommendations or advice please?

Thank you.

check your tyre pressure first...

set at around 180-210kpa max for rear tyre



if still not sufficient.... then u can try retrofit softer rear spring....probably from 1st model myvi
 

DNGFashion

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DNGFashion

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Updates:

Readjusted tire pressure back to stock recommended settings.

Have been driving in and out for one week, rear skipping during cornering at commoner's speed (30-40km/h)is still noticeable.

Any advice please?
 

DNGFashion

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DNGFashion

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During cornering with no braking and constant acceleration or sometimes no acceleration on mild uneven roads or small expansion joints on motorway (very prominent on MEX highway), I felt that one of the rear tire is lifted and soon when either one tire gain traction quickly, the rear end will skip (slight slide without tyre squirm) and I can feel it in my steering too.
(For example, if I turn right, the rear end skips left and vice versa).

Some call it snap oversteer or lift off oversteer

Having said so, this incident doesn't trigger the VSC and it is still controllable.

Let me know if you need more clarification.
 
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^pomen_GTR^

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^pomen_GTR^

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Updates:

Readjusted tire pressure back to stock recommended settings.

Have been driving in and out for one week, rear skipping during cornering at commoner's speed (30-40km/h)is still noticeable.

Any advice please?
have u tried running the tyre pressure i've recommend above?

or try this pressure instead: 180kpa~200kpa max
 

6UE5t

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6UE5t

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Yeah skipping usually means it's a bit too stiff, can be from the suspension and/or the tires. Now since your suspension is still stock and normally stock suspensions are pretty soft already, then most likely is the tires, probably too high pressures and/or rubber too hard with poor grip performance.
 

vr2turbo

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Yeah skipping usually means it's a bit too stiff, can be from the suspension and/or the tires. Now since your suspension is still stock and normally stock suspensions are pretty soft already, then most likely is the tires, probably too high pressures and/or rubber too hard with poor grip performance.
Well, other likely chance is stock suspension jammed?
 

DNGFashion

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Maybe I will go to ftuned to have the suspension system check and also at the same time check for any tyre failure.

Personally, I found that the stock tyre is incompetent

Will get back to everyone soon.

Thanks.
 

^pomen_GTR^

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^pomen_GTR^

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stock tyre is silverstone....definately it was on the stiff sidewall....


thats why i'm recommending lower tyre pressure than stock....
 

sweelt

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try open irix rear door. try sit/ press (left and right side) and see hows the rear suspension move up/down. Fast or slow.
Might be one side of the shocks/absorber give way.
 

6UE5t

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6UE5t

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Well, other likely chance is stock suspension jammed?
Maybe I will go to ftuned to have the suspension system check and also at the same time check for any tyre failure.

Personally, I found that the stock tyre is incompetent

Will get back to everyone soon.

Thanks.

It's a relatively new car so should not yet have suspension problems, let alone jammed suspension. If it does though, sorry to say that means the car quality is crap! I still think most likely is due to the shitty stock tires.
 

vr2turbo

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To us is likely the tyres or suspension. Since tyre reduce air pressure still like that , that is why maybe need check suspension....lol
 

^pomen_GTR^

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^pomen_GTR^

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Yeap I have tried your recommended tyre pressure, still it skips during cornering:confused:

Then next tyre change u can look into more comfort tyre category...


or to my earlier suggestion, change into a softer rear springs...


i believe that u were looking for better comfort?
 

vr2turbo

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Iriz original tyre size should be 175/65R14, tyre should not be that hard being 65 series aspect ratio?
 

DNGFashion

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Personal check on suspension system: seems normal being not too slow and not too fast.
Tyre pressure: I have adopted the recommended range by pomen_GTR
Tyre: 195/55/15 silverstone, which I believe is a terrible tyre.

I'm actually prefer sport handling with little stiff ride.
 

vr2turbo

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Personal check on suspension system: seems normal being not too slow and not too fast.
Tyre pressure: I have adopted the recommended range by pomen_GTR
Tyre: 195/55/15 silverstone, which I believe is a terrible tyre.

I'm actually prefer sport handling with little stiff ride.
If using 195/55R15 there are many tyre choices......:driver: