274 replies to this topic

[FTodaro]

I will pull one out and line it up with a different brand and post. but warning if you have these take a look. I TQ mine to 85ft lbs. as i always have never an issue. they are clearly designed different i will post a pic tonight.

[FTodaro]

I was going to use this as my excuse as to why Kyle beat me LOL.

[Keith Novak]

Just sent a letter to Saferacer...sucks but i will be throwing away 32 long studs new and used

 

I realize now I had a rear upright fail(new studs)its first session on track...causing the lose of a wheel and damage to the car. Unfortunetaley this was my spare i sold to someone else. At the time we all scratched our heads and thought it was wheel studs not tight or rotors that werent relief cut. Now I wonder if in fact we didnt have a stud failure

I've found that on some aftermarket hubs, pressing in new studs is a lot harder in the rears than in the fronts.  I think they may not have the same size hole as stock so the press fit puts a whole lot more stress into the hub flange.

[Steve Scheifler]

Yikes! And my main competitor lost two during Sunday's race. Scary moment coming into T1. Not sure the original source but also black. Major hazard, do not risk running on those!

[Ron Alan]

Update...

 

To their credit Saferacer has responded immediately and are taking action. I will be sending back everything I have for testing and they have temporarily taken the product offline. Also a full refund as would be expected.

 

Keith,

 

These studs pressed in nicely fYI. There has been discussion in the past about difficult to press studs. Not sure if it has been determined a stud shoulder issue or a hub hole issue. But there is a recommended size to drill the hole to for proper installation somewhere out there...Dave?

[davew]

I have only used ARP studs. Been using their various products forever. Using their Miata wheel studs for over 10 years. Never had, nor heard of a breakage issue.

 

I have installed with a hammer, with a press and by pulling with a nut.

 

There are 3 Miata studs from ARP. All are made from the same material and specifications.

 

1- Without the bullett nose tip. These fit all year front bearings and 1.6 rear hubs. These are significanly cheaper than the bullett nose design.

2- same as type 1 but with the bullett nose and a higher cost.

3- Fit rear 1.8 hubs (and all the aftermarket versions I have seen) with a bullitt nose. Same price as type 2. This is the only option for 1.8 rears.

 

All use the stock Miata 1.5 x 12mm thread for stock lug nuts. I like the 17mm head design.

 

No modification of the brake rotor or drilling of the hub is required.

 

FWIW, we torque lug nuts to 65-70 pounds. Anything more than that is overkill IMHO

 

I am glad to hear that SafeRacer is reacting quickly and properly. But I would expect nothing less from Charlie.

 

Dave

[Keith Novak]

Does anyone happen to know offhand what the right hole size is for a 1.8 rear?  I only use ARP studs, and the last ones that I pressed in did NOT go in easily, I don't have any OEMs to measure, and the search function didn't get me what I need.  I can always call, but I thought I'd ask first.

[OctaneNation]

This may seem like a silly question but what are the advantages of the aftermarket studs? I've seen very little (none?) information regarding stock studs failing but also I haven't gone looking...but my thought was that they seem to hold up fine and it's one less thing to potentially get wrong when installing.

[FTodaro]

I have attached a pick the one on the far left is the stud type that failed you can see the neck is not as long and it has a notch in it, this is the failure point. for comparison a competing stud and a stock stud.

 

 IMG_1140.JPG   126.77KB   7 downloads

[Erik Hardy]

Does the black stud have a larger diameter at the knurled portion of the stud?

[Keith Novak]

This may seem like a silly question but what are the advantages of the aftermarket studs? I've seen very little (none?) information regarding stock studs failing but also I haven't gone looking...but my thought was that they seem to hold up fine and it's one less thing to potentially get wrong when installing.

• To get the best nut retention, you want to use all the threads.  You should actually have a couple threads sticking out of the nut to be safe.  Stock studs don't allow this.
• If you use wheel spacers for a wheel offset other than 25mm, your stock studs definitely aren't long enough.
• Good after market studs are stronger.  You may not have seen stock studs failing, but studs do fail.
• You're less likely to cross thread a stud with speed tips, particularly in enduros
• They have that cool Ben Hur look to them.  Style points matter.  That's why we buy those air dams and add extra stickers

[davew]

I have attached a pick the one on the far left is the stud type that failed you can see the neck is not as long and it has a notch in it, this is the failure point. for comparison a competing stud and a stock stud.

 

IMG_1140.JPG

 

The black stud on the left is a rear 1.8 stud. The center (looks like an ARP version) and short studs (stock) are both front/1.6 rear. The flat spot is needed for installation without removing the hub from the bearing. You can also see the difference in spline diameter.

 

I agree with what Keith said about stud thread sticking out. NHRA rules require a certain number of threads to stick out past the nut. long studs really do make tire changes easier. Even when changing from rains to drys in hurry

 

dave

[FTodaro]

Does the black stud have a larger diameter at the knurled portion of the stud?

It may be for the rear as dave said but  the front is designed the say way, what i was trying to point out is that the knurled portion that fits into the hub is shorter,  and they fail right at the junction of where the threads start.

I replaced all with stock studs for now as i was doing this at the track.

[Bench Racer]

 long studs really do make tire changes easier. Even when changing from rains to drys in hurry

dave

With a little pile on Dave's comment ^. For first timer's, longer studs make starting the nut easier because the stud sticks outside the counter bore for the nut in the wheel.

[Steve Scheifler]

FWIW (very little) we have never used anything but the stock studs and aluminum lugs. We have never broken a stud or replaced one, lost a lug nut or cross-threaded one. If we do cross-thread it should damage only the lug nut and we would probably strip the nut before seriously over-torquing for the stud. Early days the hubs lasted a long time, these days I don't see stressing out a stock stud before the bearings fail,even the HD versions. It is minutiae, but I see no need to run heavier studs that stick out farther than necessary until/unless I intend to run spacers.

[Todd Green]

Does anyone happen to know offhand what the right hole size is for a 1.8 rear?  I only use ARP studs, and the last ones that I pressed in did NOT go in easily, I don't have any OEMs to measure, and the search function didn't get me what I need.  I can always call, but I thought I'd ask first.

From my notes on the ARP studs I use:

    PN 100-7719 fronts: 0.507" knurl dia., 0.335" knurl length and
    2.750" underhead length

    PN 100-7720 rears (1.8 and new 1.6): 0.579"/0.300"/2.750".

 

If you have the old style rear 1.6 hubs, use 7719, otherwise 7720.
 

Never had an issue with them (no breakage, no need to drill hubs, massage rotors etc.)  (I did have one black stud snap from Karl/ART years ago, but switched to ARP when that happened.)

[Keith Novak]

Reccomended hole size per a couple sources is 0.040-0.060 in smaller than the knurl dia.

[davew]

Reccomended hole size per a couple sources is 0.040-0.060 in smaller than the knurl dia.

That does not sound right to me. Maybe 0.004-0.006?????

[Bench Racer]

Does anyone happen to know offhand what the right hole size is for a 1.8 rear?  I only use ARP studs, and the last ones that I pressed in did NOT go in easily, I don't have any OEMs to measure, and the search function didn't get me what I need.  I can always call, but I thought I'd ask first.

 

.040/.060 smaller from memory of doing studs in other than SM sounds to small of a diameter. Didn't specify diameter on stud package.

 

ARP order/tech desk 800-826-3045
 

[Keith Novak]

That does not sound right to me. Maybe 0.004-0.006?????

I stand corrected.  I found a misquoted spec that had 0.04-0.06, and misread another one that said .1mm (.0039).  I originally read 1mm so I thought they agreed.

Per Dorman The hole should be .017" to .027" (.43mm to .69mm), smaller than the size of the knurl.

https://www.dormanpr...Sec10_Part8.pdf