Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Tyre tightening torque

With an M14 and a 40 N.m torque :
Force in the stud ~ 1700 daN
stress at the base depending on the fillet radius ~ 20 daN/mm²

But your 1932 stud is surely not an M14 (ISO)?

Dear CBY

The nut is 15/16inch, so in ISO, it is probably closer to an M16?
If so, the tightening torque would be around 80Nm?
Difficult to say.

mon32

It depends on:
. The class of the stud, by instance 5-6 tensile strengh (rupture): 5*10=50 daN/mm² , yield (elastic) limit = 5*6=30 daN/mm² which induces the limit of the constraint
. the security factor
. the force you want to apply

An M16 with a 1.5mm thread with a constraint of 10daN/mm² inducing a security factor of 3 (30/10) for a 5-6 class you get:
Force in the stud: 1280 daN
Torque: 3.45 daN.m

Force and constraint are proportional to torque.

Nota: 5-6 is a low class.
As said above a torque of 4 daN.m seems right: force ~ 1500 daN , constraint 11.5 daN/mm² security factor for a lower class 5-6 : 2.6

Paint a small touch of nail polish between nuts and wheel and check it after a running test.

Dear CBY

Thank you very much for the technical explanation.
It was very helpful.
I can drive with peace of mind.
I look forward to working with you in the future.

mon32
1932 M3W supersports beetle back