The one big problem we’re having with our Falken Azenis RT660 tires? | Garage Rescue Miata

Sponsored by
David S.
Update by David S. Wallens to the Mazda Miata project car
Nov 1, 2022 | Mazda, Miata, tires, Mazda Miata, Falken, Garage Rescue Miata, RT660

We’re having an issue with the Falken Azenis RT660 tires fitted onto our Garage Rescue Miata.

[200-treadwear tire test | Bridgestone Potenza RE-71RS vs. Falken Azenis RT660]

Excessive wear?

Lack of grip?

Groove of doom?

No. After 19 autocross days across two seasons and about 4100 miles of driving, the tires simply aren’t wearing out.

To date, we have only used up 2/32 of an inch all around as our tread depth gauge shows 6/32 all around. We’ve rotated the Falkens once or twice but haven’t been obsessive about it.

Autocross performance still feels predictable, but what does the stopwatch say? Look for some testing–new vs. old–soon.

Related note: Yes, we did heat cycle our Falkens before our first autocross.

Join Free Join our community to easily find more project updates.
More like this
APEowner GRM+ Memberand UltraDork
11/1/22 12:33 p.m.

What are you running for pressures and alignment specs and what are you getting for tire temps? 

At Southwest Motorsport here in Albuquerque we run the 660s as our spec tire for Spec Miata.  We've found that on the abrasive surface of Sandia speedway optimizing alignment and running much lower than expected pressures are the keys to getting the 660s to survive.

The exact numbers vary with the teams but We're running around 20psi hot and at least 3.5 degrees of camber in the front.  In the rear we teams typically run as much camber as they can and still hit the toe number that they like.  I think I'm at 3 degrees of camber and zero toe right now but I'd have to look at my notes to confirm.


David S. Wallens
David S. Wallens Editorial Director
11/1/22 1:03 p.m.

Some alignment settings:


1-5/8 degrees negative camber

1/16 inch toe-out


2-1/4 degrees negative camber

1/16 inch toe-in

Cold pressures are usually set at about 28 psi.


Mad_Ratel Dork
11/1/22 4:47 p.m.

I bought a used set of RT660's for my 2013 boss.  The prior owner used them in atlanta for a full season of Cam-C and 40 miles each way for each event.  (he delievered them to me in charlotte in his new tesla wearing it's new set of RT660's for the event).  I've done a full season on them minus two events and though they look like they've melted. I feel like I have got another season out of them.  

Captdownshift (Forum Supporter)
Captdownshift (Forum Supporter) GRM+ Memberand MegaDork
11/1/22 5:19 p.m.

The one great thing about high horsepower 4500 lb boats of performance cars existing, is that tire compounds have to be designed to survive the wear and tear that they put upon them. This results in sub 2500 lb vehicles simply not wearing out compounds that have remarkable amounts of grip, though if you check the pyrometer, you may find that running lower than expected tire pressure is needed in order to get the tires to warm up under use. 

dps214 Dork
11/1/22 5:28 p.m.

We heat cycled out two sets of falkens this year, both sets barely touched the wear bars and still have some amount of rubber left on the outer shoulders. The second set  was more heavily loaded and wore worse, but still cycled out before they wore out. We only had them on the car for like two months so it felt like we killed them immediately. Until I went back and did the math and they had over 200 autocross runs on them, plus quite a bit of aggressive street driving as we were trying to dial in damper and sway bar settings on the street.

te72 HalfDork
11/2/22 10:33 a.m.

"My tires last too long" is about the weirdest thing I've ever read on GRM. =P

David S. Wallens
David S. Wallens Editorial Director
11/2/22 10:56 a.m.
te72 said:

"My tires last too long" is about the weirdest thing I've ever read on GRM. =P

Figured someone would appreciate it. :) 

84FSP UberDork
11/2/22 11:05 a.m.

Are the delamination issues I hear about outliers?  Wondering if folks getting this great wear heat cycled or not.

You'll need to log in to post.

Sponsored by

GRM Ad Dept

Our Preferred Partners