One thing I have noticed is the apparent lack of any resistance to the wheels spinning on their axles.

For example, a car rolls onto it's roof... the wheels will spin for an exhorbinate amount of time before finally stopping.

In the real world, the wheel would stop much quicker.

I thereafore conclude that axle and wheel friction is not correctly simulated and is something that should be addressed at some point in the future.

Under normal racing conditions, the friction of the wheel bearings is not a significant factor. The rolling resistance of the tires alone completely overpowers it, as does the drag on the car body. It should only really be an issue if the bearing is damaged.

It's possibly not modelled, bearing friction really is a tiny fraction of the drag on the vehicle that it won't affect racing in any noticeable way.

For example, here are some numbers:
Air Drag: 122kW
Rolling Resistance: 20kW
Bearing Friction: 150W (0.15kW)

Those figures are some examples of the power required to overcome the friction of each resistance at about 150mph.

Bearing friction is modelled. Just flip your car, disengage gear, brake the wheels down to zero and then spin them ever so slightly with clutch + any gear. They will stop rotating by themselves.

This topic reminded me of something. I don't think steering resistance is modelled, or rather, the friction in the steering mechanism.

I think if this was modelled it may cut out some of the unwanted oscillations you get with a FFB wheel.

Quote from Forbin :

Under normal racing conditions, the friction of the wheel bearings is not a significant factor. The rolling resistance of the tires alone completely overpowers it, as does the drag on the car body. It should only really be an issue if the bearing is damaged.

he never said anything about bearings... just to let you know.

Quote from Mako. :

he never said anything about bearings... just to let you know.

Explain what other component would induce friction on the wheel spinning if not the bearings, barring the brake calipers exerting force on the brake disc.

I see no one has any opinions on my suggestion a few posts above?

Quote from mrodgers :

Explain what other component would induce friction on the wheel spinning if not the bearings, barring the brake calipers exerting force on the brake disc.

how about the transmission ? you should lose a considerable amount of power in the transmission regardless of which side its powered from

Quote from Shotglass :

how about the transmission ? you should lose a considerable amount of power in the transmission regardless of which side its powered from

Yes, I admit I was thinking only of non-driven wheels. The driveline and transmission would definitely slow a spinning tire down immediately if left in gear and quickly if left in neutral/clutch engaged.

Quote from mrodgers :

Explain what other component would induce friction on the wheel spinning if not the bearings, barring the brake calipers exerting force on the brake disc.

Air friction--maybe that's modelled?

Regardless, Lucretian's point is surely that it's not enough, whatever it is.

@wark: More commonly know as drag, which most certainly is implemented, albeit in a rather simplistic way (or at least I've heard it's simplistic).

I very much doubt the drag is modelled for a spinning tyre. For the body and undertray, aero drag is just a number that gets multiplied by speed to get a force. The wings are similar but some algorithm chamges these numbers for a given wing angle. I don't know how physically based that medelling is.

Oh, I thought he was refering to the drag on the car itself, not the wheel.