Sqirming under brakes?

[Bertfatal]

When I brake hard from high speed my 7 seems to "squim". It dosen't pull in any one direction but just feels slightly un stable.

Any thoughts?

A bit more info, SV, Toyo R888, standard brakes and MC but uprated pads.

 

Bertfatal

[Fathead]

Unequal tyre pressures?

 

maybe the tyres just following the changes in the road?

 

Tom The most southerly uk blatter

😬Yellow 1.6 Supersport 😬 Photos here

[CageyH]

Uprated pads front and rear, or just rear?

[Bertfatal]

New pads front and rear, Mintex F4R. The car was sqirming before I changed the pads!

 

Bertfatal

[stephen grant]

 

Have you bled the system?

 

I take it there's no sign of fluid anywhere on the inside of a wheel?

 

stephen

 

 

Edited by - stephen grant on 20 Jun 2006 16:31:16

[Bertfatal]

No I haven't bled the brakes but the pedal is nice and firm.

Would altering the tyre pressures affect the stability? At the moment 17psi front, 18 psi rear.

 

Bertfatal

[ashaughnessy]

Uneven tyre pressures can certainly cause this. This is especially noticeable on the track when you set the pressures equal when the tyres are cold but the tyres warm up unevenly and the warm pressures are therefore unequal. If this happens you need to come in to the pits quickly from a hot lap and equalise the tyre pressures while all tyres are at their operating temperature. On the road, all you can really do is set the cold pressures.

 

But there's probably loads of other possible reasons due to suspension setup etc. that are beyond my understanding.

 

Anthony

[Tom_C]

Are F4R much of an upgrade from normal pads? I found mine very squirmy until I switched to Mintex 1144 fronts with standard rears.

 

 

Cheers

 

Tom

 

FH54WLX - only the car supports ManU, honest!

 

see here - UPDATED

[CageyH]

It could also be that the rear is overbraked in comparison to the front.

You need better pads in the front, compared to the rear, unless you have a bias valve.

I run the standard pads in the rear brakes and M1144's in the front, and the car feels more stable under braking now.

[CharlesElliott]

I would agree that the most likely cause is the rear starting to lock up - especially as the 'squirm' isn't in a particular direction. Incorrect corner weights tend to mean that a particular (front) wheel locks up early.

 

Charles

---

My SuperGraduates 2006 diary

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[Mr Locust]

Do you run much toe out on the front wheels?

 

Ian

 

Green and Silver Roadsport 😬