Need advise on E90: Braking slightly out of control on 19"

[baconboy77]

Dear all,

Just got new 19" non-staggered on a E90. While braking fast in a straight line, feels like the car is not able to keep itself straight (sort of like when the tires are not catching the ground but in much shorter interval)

Should I go for wheel alignment? (have not done that since I change the wheels) or should I go back to the wheel shop and get them to check the wheel balance?

Also should I do my Eibach pro-kit before I do the wheel alignment? :screwedu:

Any better springs for E90?

Cheers,
Baconboy77

 

[mars69]

Re: Need advise on E90: Braking slightly out of control on 19"

It's a good habit to always do wheel alignment after changing the wheels. If you are planning to do anything to the suspension, do it before you go for alignment. Otherwise you'll have to spend the $60 again after tweaking your suspension. But have to bear in mind that the longer you drag, the more uneven wear you're gonna get on your tyres....

 

[centurion]

Re: Need advise on E90: Braking slightly out of control on 19"

Stability under braking is quite a complex issue, when you touch the suspension or tyres you upset it all. Besides alingment, Usually the usual suspects include camber. without a fully adjustable suspension, ... good luck with that.

 

[totoseow]

Re: Need advise on E90: Braking slightly out of control on 19"

i think u shud also look at ur tyre pressure....if u hit it hard enuf for the ABS to intervene, its pretty 'normal' for u to feel that ur car is not going in a straight line...over-pressured tyre will make you feel that ur car is skipping. under hard braking ur car pitches forward on its front 2 wheels...n its loading the front wheels a lot more than ur back. if u hold ur steering straight.....ur car shud stay straight....but ur butt may feel that ur car is not going straight.

 

[shaaz]

Re: Need advise on E90: Braking slightly out of control on 19"

Dear all,

Just got new 19" non-staggered on a E90. While braking fast in a straight line, feels like the car is not able to keep itself straight (sort of like when the tires are not catching the ground but in much shorter interval)

Should I go for wheel alignment? (have not done that since I change the wheels) or should I go back to the wheel shop and get them to check the wheel balance?

Also should I do my Eibach pro-kit before I do the wheel alignment? :screwedu:

Any better springs for E90?

Cheers,
Baconboy77

I think it's due to ur tires being over-inflated, nothing big... no worries.

YES you must do wheel aligment after doing ur Eibach pro-kit, but you dun need to when u change rims.. does not affect the aligment at all.

It's a good habit to always do wheel alignment after changing the wheels. If you are planning to do anything to the suspension, do it before you go for alignment. Otherwise you'll have to spend the $60 again after tweaking your suspension. But have to bear in mind that the longer you drag, the more uneven wear you're gonna get on your tyres....

Like what i said above, you don't need to. You've not disturbed the aligment a bit by changing tires ,rims or both so no need for aligment, balacing is all it's required.

Stability under braking is quite a complex issue, when you touch the suspension or tyres you upset it all. Besides alingment, Usually the usual suspects include camber. without a fully adjustable suspension, ... good luck with that.

True, but the suspension has not been touched at all. Camber alone in the rear only comes when the car is lowered, right?. if not camber should be neutral?

i think u shud also look at ur tyre pressure....if u hit it hard enuf for the ABS to intervene, its pretty 'normal' for u to feel that ur car is not going in a straight line...over-pressured tyre will make you feel that ur car is skipping. under hard braking ur car pitches forward on its front 2 wheels...n its loading the front wheels a lot more than ur back. if u hold ur steering straight.....ur car shud stay straight....but ur butt may feel that ur car is not going straight.

Correct, that's how it'll react, should dip abit too..

 

[centurion]

Re: Need advise on E90: Braking slightly out of control on 19"

True, but the suspension has not been touched at all. Camber alone in the rear only comes when the car is lowered, right?. if not camber should be neutral?

By default his camber for the rear should be very slightly negative on 17" rims, right (not familar with BMW rears).

If you increase it to 19" with correspondingly wide tyres, the same camber will have too much effect. May need reduction for comfort's and stability's sake.

 

[shaaz]

Re: Need advise on E90: Braking slightly out of control on 19"

By default his camber for the rear should be very slightly negative on 17" rims, right (not familar with BMW rears).

If you increase it to 19" with correspondingly wide tyres, the same camber will have too much effect. May need reduction for comfort's and stability's sake.

very slight, even with the same height and camber, it should not affect the car at all esp when it's at negative, slightly more rear grip, very safe... car will tend to understeer rather than oversteer.

 

[centurion]

Re: Need advise on E90: Braking slightly out of control on 19"

Then the easy thing to do is to reduce rear tyre pressure ....

 

[baconboy77]

Re: Need advise on E90: Braking slightly out of control on 19"

Thank you all for your help!

Did my eibach pro-kit today, will go for alignment in a week after the springs settle down.

Reduce rear tyre pressure to xx psi? (235/35/ZR19)

Cheers,
Baconboy