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Michelin tire heat cycles

Started by twg, January 14, 2003, 05:59:50 PM

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twg

I need help in determining how many heat cycles Michelin tires are good for.  I crashed last Saturday while practicing at OHR in Texas using a tire that had been last used in a CMRA race in October 2002.  The tire had good tread on it and I thought it was still good.  Now I think I had used the tire through too many heat cycles.  I realize this is a general question as rider skill and how hard tires are run affect the cycles.  But in general, especially you guys riding in colder climates, what do you use as a rule of thumb?  Also any tricks in getting the tire warmers to really heat the tires in 40 degree weather?  I thought about wrapping the the wheels and warmers in several blankets to help hold in the heat.

Thanks,

Eric Kelcher

Seems like I heard of this question before ::) anyway best bet is ask bibmen
Eric Kelcher
ASRA/CCS Director of Competition

DRU2

Chickenhawk warmers i heard are the best. i also was told too heat soak them.but i have notice that if they were sitting in the cold that they tend to get hard but that was just my observation.  ccs midwest chicago :-/

Super Dave

A used tire that gets exposed to cold temperatures begins to lose some oils that are in the tire.  That's that blue-ing that you see sometimes.  

It is a used tire that has sat.  If it sat in contact with the ground rather than being in the air, sometimes that can be worse.  

But, yes, talk to Dave.  Bibmen are good...

Warming the tire will help.  But on really cold days, the tire quickly looses heat as you ride.  I helped in working with a new tire warmer manufacturer, Baker Race Gear, and at Gateway a couple of years ago, we watched out tire temperatures go from 150 before the race, to 100 after a race.  The temperature was in the high thirties to low forties...
Super Dave

sdiver68

And to add to that....

Aren't Michelins, at all levels, pretty well known for being great tires with the caveat that when they let go, they are gone without much if any warning?

I've seen that comment on Michelins repeatedly all the way from GP racers to AMA to club Amateurs.  I know my Pilot Sports were that way, but that was a street tire.
MCRA Race School Instructor

james-redsv

Might not have been the tires, could you have hit sand, made a mistake yourself, is your suspension working correctly etc. There are plenty of other things that could have made you crash beside your tires. I was behind two guys last year going through a turn at the same speed, same lean angle, new Pirellis on all bikes. They both slid out in front of me and I did not. The only thing we could figure is they were slightly out of the race line to the outside and hit some sand. Go figure, I wound up in 2nd place instead of 4th. ;D

Dawn

QuoteAren't Michelins, at all levels, pretty well known for being great tires with the caveat that when they let go, they are gone without much if any warning?

There are some SV riders, besides Paul, that swear that this is true.

$0.02

Dawn   :)

twg

Eric, yes you heard this one on the other board.  I will talk with David at OHR before I go out next month.

Super_Dave, I did see a lot of blueing on the tire that was involved.  And I also believe I did not properly warm the tire.

James, also true OHR is not the cleanest track in our circuit and could have played a role, after the crash I loaded up and went home.  Didn't look at the track, probably should have.

I heard the bad things about Michelins going from great traction to nothing with little warning, but had not experienced it before.  I know the softs will slide and let you know.

Let me ask you guys that ride in the cold, when do you decide on softs or mediums (ie ambient temp, track temp, etc)?

Thanks to all for information.  I am trying to learn and improve.

Super Dave

The traction on the Michelin lets go hard for a couple of reasons.  

One, the traction is so high on the tires, that when it does let go, well, it lets go.  Other tires have a tendency to slide or even spool up earlier.  

Two, you have to aquire a sense of traction.  I was a big Michelin rider some time ago when I did AMA Pro stuff.  There was a certain squish that the tire had when you were riding.  That was the sidewall moving.  Just before I would make it slide, the squishy motion (highly technical description) would stop.  The tire had kind of taken a set, and I could dial in a bit of slide.

It takes some time and attention to learn it.  

The blue-ing of the tire makes me think that it might have been a bit out of its prime....
Super Dave

MELK-MAN

i noticed a big difference in "letting go" and "sliding alot" between the medium pilot and the soft pilot. I get more sessions out of the medium and it is a MUCH easier tire to ride on fast if you keep them on warmers. THe 1st lap was no fun on pilots before warmers. THe soft tire you can slide out of corners and even mid corner much more predictably but after 1 track day it was really toast. i dont compete at a level nor have the wallet for $220 tire every track day. going back to mediums to get 1 very good day-and 1 pretty good day.
  
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Super Dave

When I last used the Michelin's, I really found that I just liked the Medium better than the Soft.  Even for a sprint race.  It has to be something in the carcass construction that makes it feel different;  not just the compound....
Super Dave

twg

I have one more new set of soft compound tires.  I will save them for the first sprint races at OHR in February.  After that the temps in Texas should be a bit warmer and mediums will be the tire of choice.  Tire warmers will be the norm throughout the season.

However, changing to Pirelli's may be in the future as I am not a good suspension guy and Michelin Race 2s require a bit of adjusting. :-/

twg