Crappy roads = crappy ride...

[dgm]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

 

[tomwac]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

that's 2.2 bar front and 2.3 bar rear....I'll give it a try...

 

[playalistic]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

Same here for road. A little more for track.

To the OP - when they did the geo they should have provided you with a before & after reading. Do you have this to show us?

 

[tomwac]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

Same here for road. A little more for track.

To the OP - when they did the geo they should have provided you with a before & after reading. Do you have this to show us?

yes, I have it at home...I'll scan it in tonight or tomorrow and post it...

 

[tomwac]

so here is the geo sheet, but I guess you won't understand too much of it as it's in Dutch...but now I noticed that they did the geometry for a roadster, not coupe...are they different?

 

[tomwac]

and I have a second set of CSL's on order together with aero skirts...the second set of CSL's will be painted in gunmetal...something like this:

 

[Ewazix]

I'm finding it hard to think of a car that looks that good at twice the price, awesome, wheels look terrific

 

[indez4cpe]

I'm finding it hard to think of a car that looks that good at twice the price, awesome, wheels look terrific

The Coupe is such a fantastic looking car...

 

[Franzino]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

that's 2.2 bar front and 2.3 bar rear....I'll give it a try...

For the moment I'm using 2.5 bar (front and rear)on my 19" CSL wheels. I'm running the oem CSL tyre set-up (235/35ZR19 and 265/30ZR19). Is 2.2 bar and 2.3 bar the tyre pressure that BMW advice for the M3 CSL?

 

[Franzino]

so here is the geo sheet, but I guess you won't understand too much of it as it's in Dutch...but now I noticed that they did the geometry for a roadster, not coupe...are they different?

I don't know if the geo is different, but the suspension between the Z4M roadster and Z4M coupe is indeed different (also the steering ratio)...
My Z4M also hates crappy roads (a lot of reviews talk about this). But I never had the behavior that you described when braking hard. Did this became noticeable after fitting the Eibach springs...? Or also with the oem Z4M suspension?

Scoring 14,500Nm/degree in BMW’s torsional stiffness test, the M Roadster is pretty stiff for an open car, and despite its wide 225/45 and 255/40 rubber on 8.0J and 9.0J x 18-inch alloys rubber, scuttle shake on poor roads in minimal. Even so, it does not come close to the Coupé’s impressive 32,000 Nm/degree, which is more than double the Roadster’s rigidity.

This extra structural strength means that the engineers have been able to dial in much more aggressive suspension settings knowing they will be maintained better even under high lateral loadings on a racetrack.

The springs and dampers are a completely new set-up. The front spring rates are increased by about five per cent, but because the rears are progressive rate it is hard to put a comparative number to them. It is easier to say that that the first half of their travel is similar in rating to the Roadsters, but once that point is reached, their rate rises faster. The characteristics of the Sachs/Boge dampers are calibrated to match.

What makes the Coupé more pointy however, is the combination of a quicker 12.8:1 steering ratio (Roadster 13.7:1) and a 1mm thicker rear anti-roll bar, which combine to mitigate some of the understeer you feel in the Roadster. “Because the Coupé shell is much stiffer, we can load the chassis more on initial turn-in and so improve overall handling response,” explained BMW M’s chassis guru, Gerhard Richter, who is also one red hot test driver.

 

[daz05]

Where did you get that article?

 

[ChawenHalo]

tyre pressure is according to the doorsticker, on the CSL's...what tyre pressure should I put on the CSL's?

Try 33psi on the rear and 32 front, works really well for me.

Same here for road. A little more for track.

To the OP - when they did the geo they should have provided you with a before & after reading. Do you have this to show us?

same for me on road;

Dum question Playalistic: Why more pressure on track? I thought more heat into the tires created more pressure anyway :?

 

[ChawenHalo]

so here is the geo sheet, but I guess you won't understand too much of it as it's in Dutch...but now I noticed that they did the geometry for a roadster, not coupe...are they different?

I don't know if the geo is different, but the suspension between the Z4M roadster and Z4M coupe is indeed different (also the steering ratio)...
My Z4M also hates crappy roads (a lot of reviews talk about this). But I never had the behavior that you described when braking hard. Did this became noticeable after fitting the Eibach springs...? Or also with the oem Z4M suspension?

Scoring 14,500Nm/degree in BMW’s torsional stiffness test, the M Roadster is pretty stiff for an open car, and despite its wide 225/45 and 255/40 rubber on 8.0J and 9.0J x 18-inch alloys rubber, scuttle shake on poor roads in minimal. Even so, it does not come close to the Coupé’s impressive 32,000 Nm/degree, which is more than double the Roadster’s rigidity.

This extra structural strength means that the engineers have been able to dial in much more aggressive suspension settings knowing they will be maintained better even under high lateral loadings on a racetrack.

The springs and dampers are a completely new set-up. The front spring rates are increased by about five per cent, but because the rears are progressive rate it is hard to put a comparative number to them. It is easier to say that that the first half of their travel is similar in rating to the Roadsters, but once that point is reached, their rate rises faster. The characteristics of the Sachs/Boge dampers are calibrated to match.

What makes the Coupé more pointy however, is the combination of a quicker 12.8:1 steering ratio (Roadster 13.7:1) and a 1mm thicker rear anti-roll bar, which combine to mitigate some of the understeer you feel in the Roadster. “Because the Coupé shell is much stiffer, we can load the chassis more on initial turn-in and so improve overall handling response,” explained BMW M’s chassis guru, Gerhard Richter, who is also one red hot test driver.

Its so lovely to read just how special our tin tops are