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      12-09-2020, 09:31 PM   #23
dvas
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Quote:
Originally Posted by M2guru View Post
Was swapping between track wheels and street wheels when I tightened the first rear driver's side to something less than my goal and the stud snapped off in the hub. I removed all the others on that wheel to check them out and they look good.

I am curious about two things: 1) anyone else deal with this type of thing? I've been wondering how much of a wear items these are. 2) How would you recommend getting the remaining stud out of the hub? All that's left is the threaded part that goes into the hub...so it looks like drilling will be best, but then what does that look like (guidance)?

Thanks in advance for your thoughts.
I had this exact thing happen to me about a month ago.

I was prepping the car for the last track day of the season on the following day and was swapping over to my track wheels that had new hoosier take offs on them. Everything was done, wheels were on, car was packed, camera was setup, harness was in place, etc. The last thing was to torque my wheels and, then, snap on the driver's side rear stud.

My studs had about three years or 45 track days on them. These are of course wear items and I'm lucky and thankful it happened in the garage and not on the track. Going forward, I will be replacing them every two years. Apex wheels and studs, fyi. I've been happy with both (did the stud installation myself) but will go to bimmerworld race studs next time around, after talking to some racing friends.

In my second person experience, once one stud goes bad, all of them are susceptible and should be replaced at all four corners. I witnessed an M3 fellow instructor ending up in the wall and upside down at WGI after replacing all of the studs on the one wheel he saw a cracked stud only to have another wheel brake loose.

Anyways, my stud snapped very close to the hub. Luckily, I had an extra set of brand new Apex studs but of course had to get the old ones out first. I had to take off the rotor just to survey the situation. At first, I tried vice grips alone on the 2mm of stud showing but that was never going to work given the loctite. So, a quick trip to Home Depot for a torch and easy outs. It took me about an hour (first time) but with torching, drilling, hammering, and an easy out (first time an easy out ever worked for me), I was able to get the broken stud out. Unfortunately, by this time, the battery juicing the lights in my separate garage gave out and I was done for the night. I drove to Autosportfab in CT first thing in the morning (on four studs on that wheel) and they were able to change out all of the remaining studs within an hour and I only missed one session. (So big thanks to Paul and Autosportfab, highly recommended for those folks in central CT - they race in AER and support a number of other race cars).

Long story short, they used a stud extractor in parallel with a torch. I have since invested in the extractor, and anyone else that runs studs on track should do so as well. Hope my story helps.
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      12-09-2020, 09:46 PM   #24
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Quote:
Originally Posted by dvas View Post
I had this exact thing happen to me about a month ago.

I was prepping the car for the last track day of the season on the following day and was swapping over to my track wheels that had new hoosier take offs on them. Everything was done, wheels were on, car was packed, camera was setup, harness was in place, etc. The last thing was to torque my wheels and, then, snap on the driver's side rear stud.

My studs had about three years or 45 track days on them. These are of course wear items and I'm lucky and thankful it happened in the garage and not on the track. Going forward, I will be replacing them every two years. Apex wheels and studs, fyi. I've been happy with both (did the stud installation myself) but will go to bimmerworld race studs next time around, after talking to some racing friends.

In my second person experience, once one stud goes bad, all of them are susceptible and should be replaced at all four corners. I witnessed an M3 fellow instructor ending up in the wall and upside down at WGI after replacing all of the studs on the one wheel he saw a cracked stud only to have another wheel brake loose.

Anyways, my stud snapped very close to the hub. Luckily, I had an extra set of brand new Apex studs but of course had to get the old ones out first. I had to take off the rotor just to survey the situation. At first, I tried vice grips alone on the 2mm of stud showing but that was never going to work given the loctite. So, a quick trip to Home Depot for a torch and easy outs. It took me about an hour (first time) but with torching, drilling, hammering, and an easy out (first time an easy out ever worked for me), I was able to get the broken stud out. Unfortunately, by this time, the battery juicing the lights in my separate garage gave out and I was done for the night. I drove to Autosportfab in CT first thing in the morning (on four studs on that wheel) and they were able to change out all of the remaining studs within an hour and I only missed one session. (So big thanks to Paul and Autosportfab, highly recommended for those folks in central CT - they race in AER and support a number of other race cars).

Long story short, they used a stud extractor in parallel with a torch. I have since invested in the extractor, and anyone else that runs studs on track should do so as well. Hope my story helps.
Haha, just realized your post was from a while ago. Sorry, saw this and had flashbacks to my scramble so tried to reply asap without noticing the date or reading the other posts, including my own

Anyways, I would again suggest the bimmerworld studs for anyone looking at tracking with a stud kit. They sell two types, one for road and one for track. I have been recommended the BW race studs by folks that race in TCR and AER and will be going with those in the future. Apex is great for wheels, maybe not studs.

Quote:
Originally Posted by DRLane View Post
Definitely properly torque, but the "don't torque while hot" is dubious. Think about endurance (8hr -24hr) racing. They're going to swap a lot of wheels and will absolutely torque to spec after hours or racing.

BMWs are categorically the only ones in endurance racing that have the broken stud problems. Go to a press fit stud if you want to move on from the nonsensical risk of a thread-in stud. One less variable...
I would definitely not re-torque throughout the day when the wheels are hot. The metal expands when hot and that would be putting extra wear/pull on the studs. There's no need to retorque if you torque in the morning before the first session.

The guys that run endurance racing replace the studs much more frequently (and use race vs. show quality studs) than a typical track day junky. I don't think it's apples to apples ad definitely not worth the attempt, imo.
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      12-10-2020, 01:44 AM   #25
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Quote:
Originally Posted by dvas View Post
Quote:
Originally Posted by dvas View Post
I had this exact thing happen to me about a month ago.

I was prepping the car for the last track day of the season on the following day and was swapping over to my track wheels that had new hoosier take offs on them. Everything was done, wheels were on, car was packed, camera was setup, harness was in place, etc. The last thing was to torque my wheels and, then, snap on the driver's side rear stud.

My studs had about three years or 45 track days on them. These are of course wear items and I'm lucky and thankful it happened in the garage and not on the track. Going forward, I will be replacing them every two years. Apex wheels and studs, fyi. I've been happy with both (did the stud installation myself) but will go to bimmerworld race studs next time around, after talking to some racing friends.

In my second person experience, once one stud goes bad, all of them are susceptible and should be replaced at all four corners. I witnessed an M3 fellow instructor ending up in the wall and upside down at WGI after replacing all of the studs on the one wheel he saw a cracked stud only to have another wheel brake loose.

Anyways, my stud snapped very close to the hub. Luckily, I had an extra set of brand new Apex studs but of course had to get the old ones out first. I had to take off the rotor just to survey the situation. At first, I tried vice grips alone on the 2mm of stud showing but that was never going to work given the loctite. So, a quick trip to Home Depot for a torch and easy outs. It took me about an hour (first time) but with torching, drilling, hammering, and an easy out (first time an easy out ever worked for me), I was able to get the broken stud out. Unfortunately, by this time, the battery juicing the lights in my separate garage gave out and I was done for the night. I drove to Autosportfab in CT first thing in the morning (on four studs on that wheel) and they were able to change out all of the remaining studs within an hour and I only missed one session. (So big thanks to Paul and Autosportfab, highly recommended for those folks in central CT - they race in AER and support a number of other race cars).

Long story short, they used a stud extractor in parallel with a torch. I have since invested in the extractor, and anyone else that runs studs on track should do so as well. Hope my story helps.
Haha, just realized your post was from a while ago. Sorry, saw this and had flashbacks to my scramble so tried to reply asap without noticing the date or reading the other posts, including my own

Anyways, I would again suggest the bimmerworld studs for anyone looking at tracking with a stud kit. They sell two types, one for road and one for track. I have been recommended the BW race studs by folks that race in TCR and AER and will be going with those in the future. Apex is great for wheels, maybe not studs.

Quote:
Originally Posted by DRLane View Post
Definitely properly torque, but the "don't torque while hot" is dubious. Think about endurance (8hr -24hr) racing. They're going to swap a lot of wheels and will absolutely torque to spec after hours or racing.

BMWs are categorically the only ones in endurance racing that have the broken stud problems. Go to a press fit stud if you want to move on from the nonsensical risk of a thread-in stud. One less variable...
I would definitely not re-torque throughout the day when the wheels are hot. The metal expands when hot and that would be putting extra wear/pull on the studs. There's no need to retorque if you torque in the morning before the first session.

The guys that run endurance racing replace the studs much more frequently (and use race vs. show quality studs) than a typical track day junky. I don't think it's apples to apples ad definitely not worth the attempt, imo.
Plenty of reasons to torque your wheels during a track day. Swapping tires, checking suspension and it brakes after a violent spin to clear pebbles, to reseat a bead, to make suspension changes, etc. Again the notion you can't torque a hot wheel doesn't hold weight with a proper stud.

I've personally watched the BW race studs break repeatedly in endurance racing, and at regular track days. If you're running slicks and or aero you're putting a lot more strain on the hubs.

I would hope no one tracking their car is using "show quality" studs. I'd lump Apex studs in that bucket but to each their own. Not sure what the "attempt is" you're referencing and it's absolutely an appropriate apples to apples comparison.

Bottom line, everyone's welcome to trust threads-ins, but if you've personally broken studs or witnessed a crash at the result of broken studs why anyone would risk it of beyond me.
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      12-11-2020, 10:11 AM   #26
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I have Turner Motorsport studs on my Z4M from back in 2008. They did well on that car for about 4+ years of track days (100'ish days) with no breaks. The last 7 years the car mostly sits around except for the occasional drive. The last few years I've seen enough studs break on various cars that I simply have low trust for aftermarket quality on these. The M2 interchangeably uses OEM bolts and Ti bolts from Acer.

The quality issue applies to bolts too - so people need to do their research before buying those aftermarket bolts when running a spacer etc. On my TT RS I've had 2 broken bolts - aftermarket and longer as I needed to run a 5mm spacer to clear the KW Clubsport coils. This happened during a morning inspection of day 2 at Buttonwillow. Since they were bolts, I was able to use the broken bolt head, place it on the broken piece in the hub and simply turn it with my hand. A buddy had some spares that I threw on and completed my day, and the 1000+ mile drive back to Seattle.

This is a critical part of a car's safety for track use. Manage your risk.
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