Reason for easy spinning tires

[FFEsquared]

So I have a Focus Electric and a Fusion Energi. I was surprised by how easy it is to spin the front tires on the Focus compared to the Energi. I assumed it was due to the LRR tires, less weight and the electric motor having such a high torque at low RPM's. Then I noticed that the two cars have the exact same tires (size and spec [93V]). However the recommended tire pressure is different. The Energi is 35 psi and the Focus is 38 psi even though it is lighter. I would guess that Ford recommends such a high pressure to increase the range on the Focus to the detriment of ride and grip. I know that it is possible that the suspension engineers tuned the anti roll bars, spring rates, shock rebound and dampening in concert with the tires and tire pressures to optimize the car... but I think that they just need more range and decided to pump up the tires. Which brings me to my point... I believe the main reason for the car spinning tires is due more to the high tire pressure and the stiff suspension compared to the Energi than the torque of the electric motor. One day I will lower the tire pressures and see if that makes a difference.

 

[damania]

The change in PSI doesn't fix the grip all that much. Has anyone changed their tires with another brand/model yet?

 

[jeffand]

The FFE has 49% weight on the front axel, and 51% on the rear axel. When the car accelerates more weight is shifted off of the front axel. This makes it more likely for the front wheels to spin while doing an acceleration. I have noticed when the tires contacts a painted line during acceleration the tires are more prone to spin. It seems the road paint has less grip than the road surface.

 

[campfamily]

It seems the road paint has less grip than the road surface.

Just ask anybody who rides a motorcycle or bicycle about this!!! Even worse when it's wet.

 

[WattsUp]

I have noticed when the tires contacts a painted line during acceleration the tires are more prone to spin. It seems the road paint has less grip than the road surface.

Yup, my tires almost always quietly "chirp-chirp" over the crosswalk lines (a simple pair of lines, here in CA) when accelerating from an intersection.