'99 SL2 and Front Rotors

I have a 1999 SL2 that now has 70k. 10k ago I had the front rotors replaced
because of a Judder/Vibration on the steering wheel. About 3k later the
same problem was happening the rotors are warping and i'm getting the
judder/vibration again. Cutting the rotors only seems to delay the
inevitable.

Has anyone besides me having or had this problem? Could you please tell me
what you did to fix. My uneducated guess, is that the brakes are getting
too hot for the rotors. I have an appt. at a Vespia's shop to replace the
rotors under warranty and i'm using a high performance brake pads from EBC
Brakes.

Thanks,
Bob

 

Check two things - 1) Front wheel bearing is going slowly and leaking grease
out that is getting on the rotor. 2) Rear brakes not self-adjusting,
causing over working of front brakes.

 

Or the rotors that were used were inferior to begin with. Better to pay a
little more up front than to have to go thru this every 10k on cheap Chinese
rotors....

 

When I first went to Vespia's they wanted to install Saturn OEM rotors. I
told them I did not want that and they supposedly installed Raybestos.

Maybe I need slotted rotors to dissipate the heat?

Bob

 

So the vibration was only felt while braking, correct?

My experience has been that the wheel nuts have to be torqued to factory
spec (it's in your manual - my 97 with factory alloys runs 103 ft. lbs.).
And then 30-50 miles you do it again (my fronts usually back off a little).

Turning or cutting rotors is common, however in theory you are removing mass
and they will heat fast (potentially fading faster too). I'm not sure
running to the store and back you'd notice this as long as rotor thickness
was kept within legal spec.

From what I've read, the guys here have had pretty good luck with all
rotors, from cheap Chinese rotors to more expensive ones, even sport rotors
(drilled, slotted or both).

I'd bet you a cyber nickel it's wheel nut torque.

I've run factory rotors, Stillen's and Powerslot's.

 

I second what Jonnie said on both counts:

1) Torque the nuts correctly. If you have the click type of torque wrench,
it is no problem at all setting them to the correct torque.
2) Don't be afraid to use the "cheap Chinese rotors." I've used them and had
no problems whatsoever with them

 

I'll let you know on Fri. The appt is for thursday and I get the EBC pads
on Wed.

Thanks for the help!
Bob

 

I went through a problem with warpped rotors, replaced them with ones from
AutoZone (possibly made by Brembo but not that name) and EBC pads. I started
getting vibration again after a tire change I thought here we go again.
Someone posted a link which discussed material build up on the rotors as a
possible caus (less than 0.001 inch). At the next oil change I rubbed the
surfaces of the disk with 80 grit sandpaper in a swirl pattern- brake
vibration was much reduced di the other side - it was gone! Give it a try
YMMV. EBC pads are really good for my driving style, hard braking into
ocrners as in autocross.

Martyn

 

I have EBC's GreenStuff pads currently - nice balance of initial bite and
hot braking (not track stuff)...

 

With my '99 I had aftermarket ones installed by the dealer of all
things. I can't remember the brand, but the dealer offered two
different brands with differing prices. Still work great now the car
has 80k on it. Just make sure your wheels, whether steel or alloy are
properly torqued.

gck