Does anyone have a definite figure? The owners manual gives a range from 108Nm to 147Nm which is so vague as to be utterly useless!
Usual approach is to pick the middle value.
Middle: 128Nm / 94 ft/lb.
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I have spoken to the service department at the dealership & they tighten to 120Nm with the locking wheel nut @ 110 (as they have been known to shear apparently.) They don’t differentiate between different types of wheel in regard to torque settings which I confess I find a little odd.
Fair enough. Always interesting to hear a Service Dept’s approach 
You may also have noticed with your old NC that it was the same; a range was quoted.
Cheers,
Steve
Why would you think different wheels on the same vehicle should have different torque specifications? If the vehicle has manufacturers wheels I can’t see why there would be any difference 
I took the comment to mean perhaps between different models of Mazda that may say have 16/17/18 inch wheels. Or even steel or alloy.
So they use a specific torque for them all, which was my interpretation.
Yes, it was the lack of a specific figure which concerns me. The handbook obviously covers all models of the MX5 some of which are fitted with 16” wheels and have different power outputs. The BMW One series has several different torque settings depending on wheel size and power output for example. I don’t like guesswork or approximation especially when it comes to safety critical items such as wheels & brakes. The figure can also depend on number of wheel nuts per wheel and the thread diameter and pitch of the wheel studs. Even if the handbook had a table which covered all the different wheel and tyre sizes & the respective torque setting that would be a significant improvement & could be put in the same handbook.
I think you are unnecessarily over thinking this, use the middle figure as suggested then any inaccuracies in your torque wrench will be covered.
Remember most owners will not use a torque wrench so stop worrying and go out for a drive and just enjoy the experience.
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I can see where you’re coming from, but I’ve never had an issue with Mazda’s approach. Put simply, it’s to do with the diameter of the wheel bolts. Bigger diameter = more torque required.
With your other comments, it’s also the first I’ve heard of BMW having variable wheel bolt torque figures. I have run many BMWs and they were 120Nm across the board for years. They then moved from from M12 to M14 bolts and revised their torque specification accordingly, from 120Nm to 140Nm. This applies to a base 1-series or an M5.
Cheers,
Steve
My wheels have never fallen off from motorbike, car, caravan or motor home.
Had a few tank tracks fall off mind. 
As above middle of the road as Mazda say and all will be fine.
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Thank you all for your input. I get a bit twitchy when tightening nuts & bolts. My last Ducati had a single sided swing arm and the single wheel nut had to be tightened to a precise 176Nm! I once had a lower brake caliper securing bolt come loose on a motorcycle and it made a real mess of the rim.
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Just wanted to drop a bit of info I got a few years back - not MX-5 specific but useful nonetheless - a few years back I had a lock wheel nut key break one of its ‘teeth’ so it would no longer work. In the midst of having it resolved, a chap at the local tyre place told me that in their shop they do not see locking wheel nuts as wheel holding nuts, ie they do not torque them - they do them up by hand and then a bit of tightening with a wheel brace but very gentle from what I saw him do. I was quite amazed and actually made sense to me. I must admit I’m still not the biggest fan of locking wheel nuts…
I don’t know about other brands but if you have the original documentation that came with Mcgard locking wheel nut, they will supply a replacement
That makes sense, thank you. I had to take a wheel in for a friend from a 135i to have a puncture repaired. 140Nm was the setting specified.
An update. I contacted McGard asking what their recommended maximum torque setting was for their locking wheel nuts. This is the reply received:
“ Thank you for reaching out with your application inquiry. The McGard locking lug nuts are approved and recommended to be installed to the vehicle’s torque spec that is outline in your manual. The main reason that a key may become damaged during installation/removal is from the locks being overtightened beyond what the vehicle calls for or if the key is not fully engaged during the process. As long as you keep the key fully engaged with inward pressure and the locks are the first fastener removed and last one installed, you should not run into any problems. For the locking lug nuts we will always suggest installation/removal to be done by hand with a wrench or calibrated torque wrench with no lubricant applied. We do not suggest the use of an impact gun as that is the leading cause for fasteners to be overtightened.”
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