I've been debating what to do for the upcoming Tire Rack SCCA Bristol Championship Tour which was recently added to the national Solo schedule. I've been trying to manage tire wear the best I can, however my current set of tires is nearly toast.
I considered buying some used Hoosier A7s to run SSR for Bristol and possibly one or two additional events, however I decided against it. I don't plan to run SSR next year, so I didn't want to have to potentially change my setup to make the tires work. And I can't knowingly go to an event without trying to be competitive. :) In addition, SSR at Bristol only has 3 people in it and therefore no opportunity for contingency. Back to the Yokohamas...
Front - 295/30-18
Rear - 315/30-18
My current FRONT tires are actually not worn that bad. I plan to run these at Bristol, going into the event with 94 runs. The fronts have about 2.5/32 tread depth across the middle rib. These tires have a strange wear pattern, where each tread block wears in a convex shape, even though, when they are new, they are concave to start with. I calculated these tires to wear approximately .0019 inches per run (based on rear tire wear). This should allow 30-40 more runs on the front tires, or about 125 total runs. This is good news for Yokohama drivers, provided you can get even tire wear.
The REAR tires are another matter. Even though they just won Top PAX at the last event, they're toast. The tread depth is as low as 1.25/32. They could potentially go another 15 runs based on my calculation, but it would be a shame to lose grip in the middle of a large national event.
I do have my last set of Yokohama's, which I took off in February after only 63 runs. Initially, I wasn't considering running these, because visually they didn't look great and they've been sitting in my garage for the past 8 months. I took a measurement and they actually have ~2.5/32 left and should be good for another 30-40 runs. I will be running these at Bristol. This will also be a good test to see if the Yokohama's retain the same grip level after sitting un-mounted, and un-bagged for so long.
Here are pictures of the 94 run tires. All measurements taken from the tread closest to the gauge. The inner scale on the gauge is in 1/32 increments.
Here are pictures of the 63 run rear tires which I just had re-mounted to run at Bristol.
