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twg
01-12-2003, 01:02 PM
David, if you read this, please shed some light on what you know. From the last post it is obvious that I had a slight incident while practicing at OHR. I had been running a soft compound that was pretty shredded, but had not been through many heat cycles. Actually, the tire had only been run one day prior, but the conditions were too warm and shredded it.

When I thought the tire was gone, I changed rear wheels to a previously run medium. That tire had been run at the MSR race weekend in October. It had almost all its tread and looked like a scrubbed tire, but it had been through several heat cycles and then sat in the shop until yesterday.

When I crashed the tire gave no indication it was breaking loose. It was an immediate snap and loss of traction. Unlike the worn soft which was warning me. After the crash Dwayne looked at the tread on the tire and commented on how incredibly hard it was.

So I am asking even if the tire looks okay, how many heat cycles are about enough? Obviously it will depend on rider skill and demand. So I am asking in general what would you suggest? I would much rather swap tires too early than to rebuild the bike.

Thanks,

twg

twg
01-12-2003, 01:02 PM
David, if you read this, please shed some light on what you know. From the last post it is obvious that I had a slight incident while practicing at OHR. I had been running a soft compound that was pretty shredded, but had not been through many heat cycles. Actually, the tire had only been run one day prior, but the conditions were too warm and shredded it.

When I thought the tire was gone, I changed rear wheels to a previously run medium. That tire had been run at the MSR race weekend in October. It had almost all its tread and looked like a scrubbed tire, but it had been through several heat cycles and then sat in the shop until yesterday.

When I crashed the tire gave no indication it was breaking loose. It was an immediate snap and loss of traction. Unlike the worn soft which was warning me. After the crash Dwayne looked at the tread on the tire and commented on how incredibly hard it was.

So I am asking even if the tire looks okay, how many heat cycles are about enough? Obviously it will depend on rider skill and demand. So I am asking in general what would you suggest? I would much rather swap tires too early than to rebuild the bike.

Thanks,

twg

BrianLee
01-12-2003, 10:09 PM
Normally 2-3 heat cycles are all a tire has in it, and if it shows any signs of shredding trash it it is much cheaper to replace it than crash. Hoppe you mad it better than ur bike.
Brian

BrianLee
01-12-2003, 10:09 PM
Normally 2-3 heat cycles are all a tire has in it, and if it shows any signs of shredding trash it it is much cheaper to replace it than crash. Hoppe you mad it better than ur bike.
Brian

jonlampert
01-12-2003, 10:34 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Originally posted by BrianLee:
Normally 2-3 heat cycles are all a tire has in it, and if it shows any signs of shredding trash it it is much cheaper to replace it than crash. Hoppe you mad it better than ur bike.
Brian</div></div>I'd hate to think a tire has only 2-3 heat cycles of life. That would mean after two practice sessions and one sprint race, I'd be buying another set of tires to finish up the other sprints. I've never heard of anyone doing that before. At that rate, it may be cheaper to crash than replace the tires (maybe not, but you know what I'm getting at).

Brian, where did you get your information on the 2-3 heat cycles? Is this based on experience or is it something someone told you?

The current set of tires on my bike were brand new at the last race of last season (Cresson). I ran two practice sessions and four sprint races. I don't have enough experience yet (I've only run three races, and my first two were on street tires) to judge whether the tires had started to go away yet. I currently plan on using them for the Oak Hill practice session Feb 8-9. After going through 6 heat cycles and then sitting for several months, are they still safe to run?

Any tire experts out there that would like to chime in?

jonlampert
01-12-2003, 10:34 PM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Originally posted by BrianLee:
Normally 2-3 heat cycles are all a tire has in it, and if it shows any signs of shredding trash it it is much cheaper to replace it than crash. Hoppe you mad it better than ur bike.
Brian</div></div>I'd hate to think a tire has only 2-3 heat cycles of life. That would mean after two practice sessions and one sprint race, I'd be buying another set of tires to finish up the other sprints. I've never heard of anyone doing that before. At that rate, it may be cheaper to crash than replace the tires (maybe not, but you know what I'm getting at).

Brian, where did you get your information on the 2-3 heat cycles? Is this based on experience or is it something someone told you?

The current set of tires on my bike were brand new at the last race of last season (Cresson). I ran two practice sessions and four sprint races. I don't have enough experience yet (I've only run three races, and my first two were on street tires) to judge whether the tires had started to go away yet. I currently plan on using them for the Oak Hill practice session Feb 8-9. After going through 6 heat cycles and then sitting for several months, are they still safe to run?

Any tire experts out there that would like to chime in?

m novak
01-12-2003, 10:56 PM
I'm not a tire expert, but I've run pilots and the endurance compound slicks. I was able to get about 8-10 cycles out of the pilots. (I'm not an aggressive tire slider) And we got about 10 total endurance hours out of the slicks, plus the practices. That would be at least 8-10 cycles there too. When they started to go, it was predictable.

Folks say cold michelins will dump you on your head without warning....not sure if your's were heated up or not. Oak hill is also known for dirty spots, maybe you found one??

Hope you are all right.

Mark

m novak
01-12-2003, 10:56 PM
I'm not a tire expert, but I've run pilots and the endurance compound slicks. I was able to get about 8-10 cycles out of the pilots. (I'm not an aggressive tire slider) And we got about 10 total endurance hours out of the slicks, plus the practices. That would be at least 8-10 cycles there too. When they started to go, it was predictable.

Folks say cold michelins will dump you on your head without warning....not sure if your's were heated up or not. Oak hill is also known for dirty spots, maybe you found one??

Hope you are all right.

Mark

BrianLee
01-12-2003, 11:00 PM
Hey Jon,
My opinions are based on experience and talking too some of the tire guys. I work with Annandale Honda and we are actually working with michelin this coming yr. But wait....... this does depend on bike size , rider experience, track temps etc. Dave is prob ur best man too talk about this too. But my experiences racing a 600 in ex most guys burn up 2-3 sets a weekend, this is not a poor mans sport but u can race certain bikes and get by without spending everything u work hard for. But when you wanna step in the ex big bike classes bring ur wallet your gonna need it.

BrianLee
01-12-2003, 11:00 PM
Hey Jon,
My opinions are based on experience and talking too some of the tire guys. I work with Annandale Honda and we are actually working with michelin this coming yr. But wait....... this does depend on bike size , rider experience, track temps etc. Dave is prob ur best man too talk about this too. But my experiences racing a 600 in ex most guys burn up 2-3 sets a weekend, this is not a poor mans sport but u can race certain bikes and get by without spending everything u work hard for. But when you wanna step in the ex big bike classes bring ur wallet your gonna need it.

jonlampert
01-13-2003, 07:32 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Originally posted by BrianLee:
...this does depend on bike size , rider experience, track temps etc...But my experiences racing a 600 in ex most guys burn up 2-3 sets a weekend...u can race certain bikes and get by without spending everything u work hard for. But when you wanna step in the ex big bike classes bring ur wallet your gonna need it.</div></div>Wow!! I didn't realize people went through tires like that. The information I had received was from ameteurs running lightweight bikes (which is what I am and what I'm running). That would probably explain why they weren't burning up as many tires. I guess as you go faster, and get more power, you go through your tires a little (or alot) faster. I suppose that's pretty obvious, but I was unaware of how much faster one would go through tires in the expert big(er) bike classes.

jonlampert
01-13-2003, 07:32 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Originally posted by BrianLee:
...this does depend on bike size , rider experience, track temps etc...But my experiences racing a 600 in ex most guys burn up 2-3 sets a weekend...u can race certain bikes and get by without spending everything u work hard for. But when you wanna step in the ex big bike classes bring ur wallet your gonna need it.</div></div>Wow!! I didn't realize people went through tires like that. The information I had received was from ameteurs running lightweight bikes (which is what I am and what I'm running). That would probably explain why they weren't burning up as many tires. I guess as you go faster, and get more power, you go through your tires a little (or alot) faster. I suppose that's pretty obvious, but I was unaware of how much faster one would go through tires in the expert big(er) bike classes.

m novak
01-13-2003, 08:30 AM
yeah, I should have mentioned I was on a 600, but I'm not fast nor do I have aspirations to run up front, so my tire usage is considerably less.

m novak
01-13-2003, 08:30 AM
yeah, I should have mentioned I was on a 600, but I'm not fast nor do I have aspirations to run up front, so my tire usage is considerably less.

SMILEYMAN
01-13-2003, 08:45 AM
Hey guys, I am sure not the smartest guy on the track but on my SV650 I was getting two weekends(2 practices and 3 or four races) out of my Michelins. I dare say I could have gotten a 3rd weekend, an expert friend of mine does, but I was too chicken to try it. They do take a lap or two to get up to temp, but after that they hold fine.
I never used tire warmers, either. I got similiar results with the Pirelli's albeit quicker warmer and seemingly the same traction. I ran them 4 weekends before I discovered contingency money was really cool!
Chris Smiley CMRA 506
PS ride lap times with the expert 600's and you will do a set MUCH quicker!

SMILEYMAN
01-13-2003, 08:45 AM
Hey guys, I am sure not the smartest guy on the track but on my SV650 I was getting two weekends(2 practices and 3 or four races) out of my Michelins. I dare say I could have gotten a 3rd weekend, an expert friend of mine does, but I was too chicken to try it. They do take a lap or two to get up to temp, but after that they hold fine.
I never used tire warmers, either. I got similiar results with the Pirelli's albeit quicker warmer and seemingly the same traction. I ran them 4 weekends before I discovered contingency money was really cool!
Chris Smiley CMRA 506
PS ride lap times with the expert 600's and you will do a set MUCH quicker!

David Hirsch
01-13-2003, 05:00 PM
Tom, there is no set number of heat cycles a tire is capable of going through. It depends on several things, tire design, temperature - how high - how long, how hard the tire was ridden to name a few. Then you have to consider the time sence it was run. A new tire will last sitting in a rack for a couple of years. Once a tire is heated to operating temperature the rubber keeps degrading and does not stop. Then how was the tire stored, UV light is the enemy as are exrtreams of temperature. Then if the tire was touching anything the rubber that is touching something will change at a rate different than the rubber simply exposed to the air. So to answer your question there is no way to tell without taking all of these and other tings into consideration, it is why I make the big bucks, HA /ubbthreads/images/%%GRAEMLIN_URL%%/smile.gif

David Hirsch
01-13-2003, 05:00 PM
Tom, there is no set number of heat cycles a tire is capable of going through. It depends on several things, tire design, temperature - how high - how long, how hard the tire was ridden to name a few. Then you have to consider the time sence it was run. A new tire will last sitting in a rack for a couple of years. Once a tire is heated to operating temperature the rubber keeps degrading and does not stop. Then how was the tire stored, UV light is the enemy as are exrtreams of temperature. Then if the tire was touching anything the rubber that is touching something will change at a rate different than the rubber simply exposed to the air. So to answer your question there is no way to tell without taking all of these and other tings into consideration, it is why I make the big bucks, HA /ubbthreads/images/%%GRAEMLIN_URL%%/smile.gif

twg
01-13-2003, 05:48 PM
I kind of figured that there was a lot to it. I am still a Michelin rider, it was most likely due to rider skill and cold tires. Still I think I will throw that particular tire in the trash as I do not like it any more. Or maybe use it to get a good hot fire for burning leaves. Anyway if I can afford it, I will use soft compounds until the temps get into the upper sixties or until I regain my confidence. BTW I bet my lap times suffer from this.

Thanks,

See you guys in February,

twg

twg
01-13-2003, 05:48 PM
I kind of figured that there was a lot to it. I am still a Michelin rider, it was most likely due to rider skill and cold tires. Still I think I will throw that particular tire in the trash as I do not like it any more. Or maybe use it to get a good hot fire for burning leaves. Anyway if I can afford it, I will use soft compounds until the temps get into the upper sixties or until I regain my confidence. BTW I bet my lap times suffer from this.

Thanks,

See you guys in February,

twg

Eric Kelcher
01-13-2003, 08:37 PM
Mark Junge and Dave Swarts did a tire test at OHR about 2-3 years ago and the tires showed as much as .5 sec slower lap times on tires with a heat cycle on them as opposed to fresh tires. This was with the "new" at the time Pir/Metz, Michelin Pilot and Dunlop 207* (I think it was the star maybe normal 207)

Eric Kelcher
01-13-2003, 08:37 PM
Mark Junge and Dave Swarts did a tire test at OHR about 2-3 years ago and the tires showed as much as .5 sec slower lap times on tires with a heat cycle on them as opposed to fresh tires. This was with the "new" at the time Pir/Metz, Michelin Pilot and Dunlop 207* (I think it was the star maybe normal 207)