Cruise control out of control…

[Funtasto]

…after having the tyres changed by the dealer, the cruise control stopped working as before: now, if set for example to 120kmh it goes automagically up 123kmh, always 2-3kmh higher as displayed in blue - also, it „pumps“ almost all the time, slightly accelerating and breaking alternating. The dealer has no clue and did not change anything except the tires. Does anyone has the same behavior lately? Perhaps the lower temperatures? In any case I have an upgrade from R32 to R34 scheduled soon, but my hopes are low that it will fix this specific problem…

 

[CybersterWatcher]

Silly question, what PSI does the car think the tyres have, and how does that compare to an external reader?

 

[leomindel]

What size tyres have you now got on and which model Cyberster to compare to the factory spec.

 

[Funtasto]

The 4WD model - tyres are both, summer and winter, 20“. The winter ones read: 245/40 R 20. Summer I didn‘t memorize.

 

[leomindel]

Hi on mine the tyres are different sizes front and back

The back are 275/35 R 20
The front are 245/40 R 20

Leo

 

[Funtasto]

Hmm… intriguing - will confront my dealer when (finally) making the upgrade to R34 in 2 weeks. Do you know why front and back are different with yours?

 

[leomindel]

Hmm… intriguing - will confront my dealer when (finally) making the upgrade to R34 in 2 weeks. Do you know why front and back are different with yours?

That is the size the GT ships with

MG Cyberster Cyberster GT * Electric 510 (375 kW) tyres | MICHELIN UK

It is usual on a sport car to have fatter tyres on the back.

 

[onkeldunkel]

Hmm… intriguing - will confront my dealer when (finally) making the upgrade to R34 in 2 weeks. Do you know why front and back are different with yours?

It’s like that on many cars, including Tesla Model S, BMW and Mercedes. It’s called a staggered setup/wheels.

 

[Funtasto]

It’s like that on many cars, including Tesla Model S, BMW and Mercedes. It’s called a staggered setup/wheels.

…indeed - the ones in the back are different, so, this is not what is causing those problems.