Knockon Nut For Brand Lotus Wheel

[CBUEB1771]

We don't see Brand Lotus wheels much in the US and I was very interested by the images of the wheel that Mark posted in the boot floor support thread. The surface contacted by the knock on nut is radiused, unlike the conical surface of the pressed steel wheel. Is there a different knockon nut for the Brand Lotus wheel? The service parts list suggests not, but I don't think the alloy wheel is listed either. I ask because I bought a set peg drive Minilites for my +2S recently. The Minilites have the same radiused contact surface as seen on the Brand Lotus wheel.

[ppnelan]

Yes, there are wheelnuts marked 'For alloy wheels only' for these wheels.
The steel wheels LOOK like they have a conical face, but don't they only have a 'line' contact with the nut too?

Matthew

[CBUEB1771]

Matthew,
Thanks for your prompt reply. You raise an interesting question about contact between the nut and the pressed steel wheel. I'll have to check mine this weekend. Does the "alloy wheel only" nut have a different profile in the contact area?

[Elanintheforest]

I have heard of these knock-on nuts with 'alloy use' on them, but I've never seen one. The cars I have that are fitted with alloys all have steel inserts in the wheel centres which the nuts tighten up to. Does this then make them comparable with the steel wheels? I have a set of knock-on Wolfrace and a set of 4 spoke Revolutions for the Plus 2, and they have similar steel inserts.

Mark

[ppnelan]

Having checked a spare 'normal' nut with a steel wheel, it does appear that they have mating conical faces i.e. more than just a line contact. I will compare an 'alloy wheels only' nut with a 'normal' one next time I have to remove one, as the spares I have seem to have been turned down to make them identical to the 'normal' ones...
I have been led to believe that the cone angle was different for each type of wheel nut.

The line contact with alloy wheels, and the fact that there are probably a lot of 'normal' nuts used with alloy wheels, explains why it is common to have them come loose!

Matthew