Quote:
Originally Posted by dogbone
Sorry to hear you had the broken stud. Your break shown in that photo is exactly the same as how mine would break.
Yeah....getting that broken piece out of the hub is painful. I got decent at removing it and sometimes was able to remove it at the track, but there were times I could not get it out and it ruined track days. I had a couple that even a shop could not remove and I had to replace the hub. Most of my breaks were on the front. It got to the point that I kept spare front hubs in the trailer and would simply replace the whole front hub to salvage the day and deal with the broken piece later. Replacing a front hub is not hard once you remove the entire brake system. It’s just four bolts—-much easier than using a Dremel to carefully cut a notch into the the stud while not damaging the hub threads. And then using a propane torch hoping to break the loctite. And then trying to use a screwdriver in the notch I had cut to rotate the broken piece out. It worked sometimes but not all the time.
Since you are tracking and breaking studs, I highly recommend going to 14mm press-in. The way the stress is distributed is fundamentally different than a threaded stud. With a press-in, there are no threads to reduce shank thickness inside the hub and there’s no thread stress/tension inside the hub. And the 14 mm press-in stud is actually 14.7mm of steel inside the hub flange compared to a shank thickness of 10.5mm of steel on a threaded 12mm stud (when you account for the shank thickness lost due to the threads). You’re working with 40% more steel at what clearly is a high stress spot. That is a MASSIVE difference in shank thickness.
My friend who I referenced in the story above has since purchased the Core4 14mm press-in solution for all four corners as well.
The irony is that I believe the Core4 14mm press-in is the best solution out there for our platform, but it’s actually less expensive than going with F80 M3 threaded 14mm hubs.
So—-were you able to set a new personal best with the new pavement at Chuckwalla before you broke the stud? Many people at our event in November was crushing their old times. I ran both directions that weekend and set new PBs in both directions.
|
Thanks a ton Dogbone and Core4 looks like a great solution. Thought the MSI Studs and M14 size (F82j would have a longer life than 16 months, but maybe operator error played a role - using impact gun to remove and install, but install to about 60 ft lbs, then torque wrench to recommended 85 ft lbs. There’s always that couple times at the shop where they over torqued even after instructions.
Luckily, didn’t use Loctite, so hoping to get this out myself. It looks like you didn’t drill into the stud, but used a dremel and screwdriver? Any reason not to drill into the broken stud?
Love the new surface at Chuck, just amazing. PB‘s are still above 2:00 as it’s about my fifth or sixth time at this track (slow learner), but still stoked.