[DanEC]

Originally Posted by KevinW

this is something i have never properly understood.

On the little race car project i am involved in (although not mechanically), my mech engineering colleague has assured me that the pins on a knock-on wheel are for placement of the wheel only, and that all the drive torque should be provided by the tightly clamped friction between rear face of the wheel onto the hub face, and that this load is then spread over a large surface area. Hence ive been told the drive surface should be fitted dry.

But it seems on cobra knock-ons, everyone considers the alignment pins provide the rotational torque.

I would be interested to hear any comments on this.

For what my Civil Engr degree is worth - I think you are correct. As long as the spinner is tight (approx 350 ft lbs torque on Corvette KOs I know) the wheel is clamped on and the pins are just for alighnment and along for the ride. If ever that spinner looses it's torque (and resulting clamping tension on the wheel) those pins might keep the wheels from freewheeling on the hub but they aren't going to keep the wheel on the car.