NC Miata -- Hub problems at the track and the solution -- RX8 hubs up Front + Mazdaspeed Rears
So when it comes to nearly all of the Miatas (NA-NC) the wheel hubs are a known weak point. They can fail, sometimes catastrophically, leaving the wheels up front just held on by the brake caliper, and in the rear the brake caliper and maybe the axle if you're lucky. If that doesn't sound terrifying, well then you're just a special kind of crazy! Here's a few more photos of a fellow named Troy Velazquez's issue with bearing failures at the track!
The known solution prior to 2022 largely has been to utilize the RX8 hubs up front, and the RX8 hubs in the rear.
The front is fairly straight forward and mostly just bolts right up. It even has the same speed sensor for ABS. You can just look up a 2009 model year RX8 hub, and sure enough it's a simple and straight forward task.
The rear RX8 conversion however requires swapping out a wide variety of parts however and runs into the thousands to repair if you're getting mostly new parts. On a budget track car, especially a lightweight momentum car like the NC Miata, that's a bit ridiculous.
On our track Miata we went with the RX8 hubs up front as they are readily available from a variety of locations and bolt right on. I've simply put off the rears on our track car, but it is constantly in the back of my mind as something I need to get on.
So knowing the RX8 rears are a bit of a cluster to install on the NC and spendy, any alternative would be preferable. Welp, a recent development (2023) from Mazdaspeed has a new option for beefier hub flanges and bearings that all fit right onto an OEM setup. Here's the only additional information I could find:
https://specmx-5.com/wp-content/uploads/2023/02/SMX-Comp-Rear-Hub.pdf
Again, to cite Troy Velazquez, he had not one but two rear bearing failures on the track with their NC, but has had no issues since switching to the Mazdaspeed units. Their car also owns six active lap records and four class championships, so they'd know if these were not up to the task.
Here are some measurements Troy took as well to show the difference in the hubs. First up are the OEM hubs as picture...
...and below are the new Mazdaspeed hubs
How to get the parts:
So MazdaSpeed ie Mazda sells these parts directly through their website... and they really don't make it easy to order. I was able to navigate it all for you though so here's the steps.
- Naviage to their website at https://store.mazdamotorsports.com/
- You should see a login at that page, and a link to register for an account. Register for an account.
- You will be given three choices of who you are. Click the top one which should say "I DO NOT RACE"
- Fill out the form. If you don't know, randomly select something. They don't actually seem to care since you aren't trying to get these parts on contingency or anything else like that.
- You should be accepted. Please note, you may get a strange email like I did that just says "Not Agreement Type". Yep... that's actually all the email they sent me said.
- You should be taken to a... shopping-cart-esque page. There is a table in the middle of the page, and the second column from the left says "Search by part #"
- Lookup each of the following items, adjust the quantity to 2, and click the shopping cart icon to the right of them to add them to your cart
- Hub Bearing - 0000-04-5531
- Hub Flange - 0000-04-5530
- Once complete and you have TWO OF EACH OF THE ABOVE ITEMS, Scroll down below the primary table and click the checkout button.
- Proceed and fill out all of your information and credit card info as you normally would so as to order the items.
How to Install the parts
More information to come. I have not done this to my own NC Miata, and while others have done it, I haven't seen a tutorial yet on how to do. I believe the process is simple, but we shall see!