How many/much thread is adequate ?

[30psi 4agte]

As the title states..... How many threads on a wheel stud would be deemed enough ?

In general i am led to believe you go by the stud /bolt dia and use that as the length required..

IE a 10mm stud requires 10mm of thread to be used to enable a good grip on the stud....

Also .....what is deemed safe as far as scrutineering goes ?? -- i have herd for certain events scrutineers dont like "dome" wheel nuts as they cant see how much thread is holding on the wheels..


The reason i ask this is ...... I have to space out my new wheels approx 8mm and this will leave me with only 9 mm of thread on a 1/2 inch stud...

My old wheels used only 8mm of thread to hold the wheel on ....I was told this was ok by the tyre shop .... but it doesnt seem like much..

[roadsailing]

i had to ask myself this question recently, general thread rule is for example 8mm engagement on an M8 thread (steel on steel) but more in alloy (1.25 diameters engagement)

my wheel nuts are flush with the studs (no protruding threads) and im not that comfortable with it, even though the wheel nuts are longer than their diameter.

some drag racing rules state you must have a stud diameter worth of protruding thread, so it depends who you talk to i guess.

problem is, if you cut down your wheel nuts, it would look like its safe, but would it be? if you wanted to go all out, fit new studs, i'd like to but just CBF!

[Billzilla]

1.5 times the diameter of the stud is enough.
And to do the job properly, the wheel studs do not locate the wheels, merely hold it up against the hub and the hub locates the wheel.
This is so the studs only work in tension, and don't have to cope with bending forces as well.

[30psi 4agte]

Hmmmmm so i take it my 9mm of thread on a 1/2 inch stud may not be enough ?

[IN 05 NT]

better safe then sorry,...just speak to GU11TY...he had a wheel come off as he was turning a bend....(due to spacers and not enuf thread),...ran straight into a NEW BMW, $20,000 damage, not insured,

just get some longer studs and slap them in,

[30psi 4agte]

just get some longer studs and slap them in,

Easier said than done when it comes to alloy hubs.... But i hear what you are saying.

[IN 05 NT]

if you can afford alloy hubs you can afford the studs

[30psi 4agte]

Yeah thats not the drama.....

It is how well the new stud will fit into the hub after the old one has been pushed out !!

Its not like steel where the hole will remain basicly the same. Once the old stud has been pushed out of a alloy hub the is a possibility that the new one will be a "sloppy" fit.

[oldcorollas]

i wonder if you could get a new stud either oversize and then machined to suit the alloy hub?

9mm is not much

[roadsailing]

if its a sloppy fit, then apart from being a bastard to engage and the stud falling out, there will be no major issues as long as the stud doesnt freespin in the hub. friction is what holds wheels on hubs, not studs or centrebores.

9mm engagement on a ~12mm stud is definately not enough!

[30psi 4agte]

Where is the best place to find longer studs ?

[fixeruperer]

you can get them from repco, veals or coventries you can also get arp ones just give a retailer the size and thread and they can get you wont you wont.

[LeeRoy]

Maybe a bolt wholesaler. Linden buys them from some auto shop but im not sure of the name.

[oldeskewltoy]

Well in the "olde" days... with conventional lug nuts(about 20mm tall) the rule was a minimum of 2 threads showing.....

[Cuzzo]

When i changed my studs in the axels the part which grips into the axel was larger than the studs that were in there originally needing to be drilled out. So you find that new ones could be slightly larger.

However you may already have new ones in there.