Heat Cycling Tires Revisited/Location Of Cording=Over Inflation/Old Tires/Any Kumho’s - The Unofficial BMW M5 Messageboard (m5board.com)

Anita · 4th August 2004, 03:19

......Out There?

I found this thread re the need to heat cycle and shave tires.

Heat cycling/shaving comp tires- worth it?

I’m currently using Kumho Victor Racers V700’s and was told by Tire Rack if I had them heat cycled I could expect a 25% increase in tire life and that it was easier to maintain the sweet spot on the tire once you had them broken in. Has this been anyone’s else’s experience especially with Kuhmos?

Also when my front tires corded last Friday, it was in the center of the tires (I had the tires flipped on the wheels to help get maximum use out of the tires—the outer shoulder of the front tire is what looked like it was wearing most—was this a sign I’m running my tires with too much air pressure in them? I know the pressure will to vary depending on whether I’m doing 30 minute sessions or only 1.5 laps from a standing start, the type of track, weather, etc. Any insight?

Finally, can anyone help me find Kumho Victor Racer V700’s for the rear of my M Coupe—size 255/40 ZR17? They are on the boat and due back in stock at Tire Rack 9/30—local dealers don’t have any?

I can buy the fronts from an individual—how old is too old for an R Compund tire? How should they be stored?

Thanks very much!!!

Anita

Stem · 4th August 2004, 14:55

The outside edge wear is from not enough negative camber. That can be fixed with a new adjustable suspension!

I have outside edge wear on the M-5 and on the Porsche even though there is a limited amount of adjustment on the P-Car! I moved it to -1.0. The guys with suspension changes can get the -2.5 which seems to be optimum! Since the M5 wear is just about the same....that would seem to be the best though most expensive solution.

A guy at WGI had a suspension on his M5 and was easily able to out-.corner me at every corner since he could use the entire contact/surface area of his front tires.

I use to flip-the-tire method to optimize my R-compund tire life. It is cheaper then a new suspension! Or don't drive fast on the track...but who wants that as a solution?????

Lscman · 4th August 2004, 19:42

Quote:

Originally Posted by Anita

......Out There?

I found this thread re the need to heat cycle and shave tires.

Heat cycling/shaving comp tires- worth it?

I’m currently using Kumho Victor Racers V700’s and was told by Tire Rack if I had them heat cycled I could expect a 25% increase in tire life and that it was easier to maintain the sweet spot on the tire once you had them broken in. Has this been anyone’s else’s experience especially with Kuhmos?

Anita

Heat cycling does indeed increase tire life when NEW, FRESH tires see max G's "out-of-the-box". As a result, folks who install a fresh set of non-heat cycled tires and tow their car to the track (strapped to a trailer) will see greatly accelerated tire wear. This is the world racers generally have to deal with, since they are unable to put street miles on their illegal car.

The next question becomes....Are there alternate methods to heat cycle a tire, if you have a street legal car?? Heck yea & EASY! Most tire companies agree that heat cycling involves driving 10 miles (or more) at highway speeds and parking the car overnight for the rubber. The molecular structure of the rubber somehow changes after curing, when substantial heat is introduced, followed by cooling. The rubber hardens some & becomes more resistant to wear, tears & chunking. **Why pay for a dealer to do heat cycling for you? I find it very convenient to drive my street legal track car around on fresh tires before visiting the track. A week of commuting will do a much better heat cycling job than a silly tire rolling machine. Dropping the pressures some from factory max values (before driving) will raise temps & accelerate heat cycling. Alternately, elevated speeds (65+ MPH) for 15 min or so will do it. Just be careful you don't hit a pothole with lower pressures.

Anita · 5th August 2004, 18:30

Thanks to you both for the info. I may be getting camber plates in the near future to allow for more adjustment. And Lscman thanks for your (usual) practical (money saving) years of experience and knowledge .

Anita