billla

Folks, I don't want to kick off another "who's better" autocross tire discussion. At some point, everyone's just got to make the decision...and mine is the V710 in 275/305 on my stock Z06 rims. I may be wrong, but that's part of the learning process, right?

I'm putting together my budget for this year and I'm wondering if I need to budget for more than one set. I'll be trailering the tires to the event, and I'll be running 15 or so events this year usually with 3-4 runs/event.

How many runs/events should I plan for from these tires?

Should I pay TireRack to heat cycle them?

For any Seattle-ites, any local sources vs. TireRack?

Any other tips?

Thanks!

Datawiz

I believe the Kumhos last longer than the Hoosiers, but I can tell you, I only get 3 competitive weekends out of a set of Hoosiers on m Z. I run about 18 - 20 weekends a year. You may be able to last the season, but not sure how fast you'll be at the end of the year.

I have mine heat cycled by Tire Rack. Some will tell you it's a waste of money. The one set I didn't heat cycle corded rapidly.

ltborg

My Kumhos have lasted over half a season (maybe 25 events in a year) and were still pretty good with two drivers at most events and several two day events. I was very careful to take good care of them, just in case (cool dry dark place for storage, didn't let them overheat, etc). They still felt ok but two are out of tread and would probably cord if I ran a few more events.

Datawiz

Also, I run on concrete.

The surface you run on plays a big role on tire life.

Solofast

The older they get the more you need to get them hot before they will work.

With two drivers we were finding that after about 65 runs (4 runs x 2 drivers x 8 events) the tires started to fall off in performance. After that, you need to get them pretty hot before they will work at well. They were no where near cording at that point but they weren't fast.

With one driver you are probably going to get most of a season out of set, but near the end of the season they are going to be going off.

I never had the tire rack heat cycle mine, but I generally took them to a test session where I could do it right (get them nice and hot and then take them off the car, as opposed to trying to do it at a typical event)...

GS023

15 events x 4 runs. 60 runs, you should easily get by on one set IMHO.

mountainbiker2

My budget is 5 to 6 sets. Depending if I'm using Hoosiers or Kumho's. You probably can get at least 100 laps out of Kumho's far as rubber depth goes. You can roughly figure at 50 laps they will be 1 second slower. 100 laps at least 2 seconds slower. Based on a 60 second autocross course. I've only used 2 sets of Hoosiers. From what I can tell, you can go about 60 laps before they will cord. Not sure how slow they are by then.

Steve

EvilBoffin

From the feedback I've heard from several national-level drivers, this seems to be the general consensus on Kumho life characteristics.

Assuming they're initially heat-cycled and stored properly, the performance of the 710's is best when they are fresh, then it falls off steadily, usually quite dramatically before the tread is gone. In comparison, Hoosier A6's tend to stay pretty consistent until the tread is physically gone and cord is showing.

The total number of 'competitive' runs you can get out of them will be affected by the surface you're on, the pressures you use and how long they are stored between events, too. Obviously, there's lots of variables to tire life...

Aaron Quine (rasrboy on this forum) works for Kumho, and can probably offer some tips to improve the useful life span.

.

TedDBere

Kumho's will give you 20 great runs and then they start to fall off. They seem to last forever though. FYI - Kumho backed out of contingency monies this year.

The A6s I've gone through have remained fast for a long time and I haven't corded a set yet despite running up to and over 120 runs. I could never have said that for the A3S05s or the A3S04s. The A6s are just that much better.

If you overdrive any tire it will cord. Most new drivers cord their tires due to over agressive corner entry. IMHO. If you don't stuff the corners the 710s will most likely last you the entire year, but if you decide to run at nationals you'll need a fresh set to be competitive.

96solo

One thing that is missing here. As you get better and more demanding on the tires, the less track time you get from your tires. So you need to talk to someone of a similar skill level that has run the two tires. I used to get 40 runs off of a set of Kumhos in autox, but not anymore. Better skill level and better times equals shorter life of the tire, even if well maintained.

I can toast a set of Hoosiers in a weekend of track time in getting a Time Trials win.

jwt1603

Back to the original question of 710 auto-x lifespan, IMHO you should be able to get the 15 weekends out of one set but as noted above after about 10 - 11 the tires need a lot more heat to work right. You'll easily notice the difference when they start to fall off from their performance peak.

I have two drivers in the car and we run NCCC events and we do two day weekends quite often with 10 to 14 runs each day for each driver so we'll put 40 to 56 runs on the tires in a typical weekend. What I have found is that since we run two drivers we don't heat cycle the tires as much, they get hot and stay hot for the day. This seems (to me) to make them last quite a bit longer than with one driver where they heat cycle more frequently with the cool down time between runs.

As far as having Tire Rack heat them up for you, I used to do that but stopped a couple of years ago. If I did high speed instead of auto-x I would probably have Tire Rack do it to prevent chunking the tires.

All that said we'll get three, maybe four weekends out of a set of 710s. Bear in mind that's a lot of runs for us. As noted above, the surface you run on will make a difference too.

Just my thoughts of course.......

Solo2GS

Anyone have any luck with tire treatments and extending the life? Can't remember the brand names I have seen, but its where they apply several coats to help keep the tires fresh?

Solofast

I tried Forumua V, and have had great results with it on some tires, but it didn't seem to help the V710's all that much. Generally, by the time they are that hard I am using them for test and tunes and only then to get some seat time early in the season to get some of the cob webs out of the brain, but it wasn't like they were fresh after they were doped...

billla

Thanks, folks - this has all been very helpful!