Higher profile tyres at rear for comfort

[Zulu4]

I no longer like a rock hard ride but I still enjoy the Z4 for its speed and open top motoring. My Zed has 18" wheels with sports suspension.
The car was getting too bumpy for me so I decided to experiment with slightly higher profile tyres at the rear.

I changed from 255/35R18 (Michelin) to 255/40R18 (Vredestein). It does seem to have made the ride more compliant.
The speedo will be different by 4%, but I hope this will just counteract the conservative reading that the manufacturers tend to build into speedometers for legal reasons.

It also fills the rear arches more with no rubbing.

 

[Zulu4]

Curiously, when I look at this thread on my phone the text that I wrote along with the photos does not appear. It displays OK on my PC though.

 

[smorris_12]

You must have selected black text - I can only see it on my phone if I highlight it (I've got a black background.)

I always used to find the biggest difference in tyre comfort was being either side of 50 profile where the side wall changes from curved (50 and above) to flat (45 and below.)

 

[Zulu4]

You must have selected black text - I can only see it on my phone if I highlight it (I've got a black background.)

Off topic - My original post was written on my PC with the default black text on a white background. The Z4-forum app has a black background with white text on my phone, so what do I need to do to ensure my PC's black text can be seen on the app's black background ? (without me having to write in orange )

 

[Mr Tidy]

My Z4 had 19" CSL replicas fitted when I bought it, with 265/30 rear tyres.

Everyone has some sort of CSL style so I went back to OE 18" wheels and went up a profile to 255/45 rears. They filled the arches well but in all honesty I didn't notice any improvement in the ride quality.

But maybe my very stiff coil-overs are the real issue!