Tire Warmers

[Hotfoot]

Help, I am confused about tire warmers. I recently started using them, at the insistence of my track buddies and tire supplier. The logic from them was that I wouldn't have to 'waste' the first few laps warming up tires, and that the tires would last a lot longer due to reduced heat cycles. I do enjoy the good grip on the first laps and the increased compliance of the warm tires, that's working out well, however it seems to me that my tires are NOT lasting as long as before - they got slippery (kinda greasy) in just two track days.

 

This would seem to indicate that I am 'cooking' the tire. So, how do you know how long to run warmers? I asked a tire guy at the track and he said, "you have to run the warmers at least twenty minutes to get the rims and tires warm." Then I asked him how long I can leave the warmers on, and he said "not more than twenty minutes at a time." Uh... so I have to run them EXACTLY twenty minutes? "No, you have to run them at LEAST twenty minutes." Eventually I gave up on that conversation.

 

Anyway, the track days usually run twenty minutes on track, forrty minutes off. Most people seem to leave their warmers on the whole time between sessions. My warmers have only one temp setting, no adjustment. I do not have any instructions with them, I bought them used.

 

How is this supposed to work, and what am I doing wrong if I am overcooking the tires, or how do I know if I am?

[hubbard_28]

I think it's worth spending the money on new tires for me, and I'll get some warmers when my wife graduates, but I was also of the impression that it would wear the tires out faster. I know it sure seems to. I also know people who keep them on way over 20 minutes. WAY over 20 minutes. There is a temp reading on the warmers I've seen that tell them when it's where the tire should be. But 20 minutes sounds right, because it does have to get the rims warmer also. Sorry I'm not much help. It's something I'd like to know also, though.

[jodypresti]

This is a great thread. I too run warmers and have not noticed an appreciable difference in tire life. At most track days by the time I get the warmers off and roll down pit lane the wait for the session to begin must cool the tires down.

 

I haven't changed my first lap riding in that I am cautious making sure the tires have a good lap or so (summer heat on the east coast helps this) before approaching full lean angle.

 

I just completed four days with CSS and didn't see the coaches running warmers. However, they are doing 2-3 times the amount of track time and save for lunch, I can probably assume that the tires never really cycle.

[hubbard_28]

I start on cold tires, and have to do two well paced, but cautious laps. In the winter it's one SLOW lap and two faster paced, yet still cautious laps. I can't wait to get warmers.

[fossilfuel]

Hotfoot,

You just need to slow down!

 

I was thinking about this. There are many factors that come into play here from how long you have the warmers on, tire pressure, track condtition, track temperature and the way you ride. Is it both tires that are getting greasy? Where is the wear? What is the tire compound?

 

I normally fill my tires with air at the track with in a couple of pounds over my normal cold tire pressure, I heat the tires 40 minutes before my first track session and do not take the warmers off until the third call. I immediately put the warmers back on after each session and check the tire pressure 4 to 5 times during the day. During lunch break, I turn the power off but leave the warmers on until about thirty minutes before I go out for the first session after lunch. After the day is over I unplug my warmers and leave them on the tire for as long as I can to let the tires cool at a slow rate.

 

I was just admiring how beautiful my rear tire looks. I'll take a picture and post it in the thread later. It has three track days on it.

[Hotfoot]

Hotfoot,

You just need to slow down!

 

I was thinking about this. There are many factors that come into play here from how long you have the warmers on, tire pressure, track condtition, track temperature and the way you ride. Is it both tires that are getting greasy? Where is the wear? What is the tire compound?

 

I normally fill my tires with air at the track with in a couple of pounds over my normal cold tire pressure, I heat the tires 40 minutes before my first track session and do not take the warmers off until the third call. I immediately put the warmers back on after each session and check the tire pressure 4 to 5 times during the day. During lunch break, I turn the power off but leave the warmers on until about thirty minutes before I go out for the first session after lunch. After the day is over I unplug my warmers and leave them on the tire for as long as I can to let the tires cool at a slow rate.

 

I was just admiring how beautiful my rear tire looks. I'll take a picture and post it in the thread later. It has three track days on it.

 

Thanks for the info Fossil... here are some answers to your questions.

 

I am running Michelin Power Race tires (PRC front and PR3 rear), and have been running this model of tire for a while. I was getting 4 track days and never noticing any decline at all in performance, without using warmers. After 4 or more days I'd change the tires but they still looked great and I either sold the take offs or kept them for future use.

 

Now I am running with warmers and in the middle of my SECOND track day on a set of tires I noticed I was having trouble with the back tire sliding around a lot when slowing for turns. Later in the day I started to notice less grip on the edges on the front tire. I never noticed any trouble with rear tire leaned-over drive slides, but I would not say I was pushing it very hard since it was sliding all over PRIOR to the turn! The tire wear looks fine, same as it did without warmers, but I see some blueing on the edges that I don't normally get. There is wear on the sides of the tires but very little wear in the middle. I get little balled up bits of rubber on the outer 1/4 of the rear tire, but they are not streaked or melted and they are small bits.

 

I ride 20 minutes, then put the warmers on after the session, so they are on for 40 minutes between sessions. I run like this all day with no lunch break. The warmers have no temp display but they do turn on and off to maintain a temperature, there is an indicator light for on or off. Tire pressure is 30 in front and 22 in back and I do not typically check it through the day.

 

Before anyone mentions it, I do realize that it isn't particularly difficult to ride without warmers and that you can get good tire life without them, but I am trying to get used to them so I can use them for racing, otherwise I get clobbered in the first lap. These tires have less grip when cold than the street model tires like the Pilot Power, so I have to go pretty slow in the first lap or two. The new PowerOnes are REALLY slick when cold and SUPER stiff, I don't think I can run those at all without warmers.

 

So, with all that info... do you think I am over-cooking my tires? Is there any way to tell?

[fossilfuel]

Hotfoot,

Drum roll, please..........................................................................

................. I think, if this is cold tire pressure you are giving me, that you are to hard in the front and to soft in the rear! Don't worry about the blueing thats normal.

This one is Dunlop slick 31 psi hot http://i160.photobucket.com/albums/t172/dt...51/IMG_7439.jpg three track days

This one is Michelin slick 27 psi hot http://i160.photobucket.com/albums/t172/dt...51/IMG_7441.jpg one track day

 

I too was slipping around on the Michelin rear. A 22 psi cold tire would be about 27 to 28 psi hot. I have always seen more wear on the Michelin power race than any other tire I have used.

[fossilfuel]

DISCLAIMER:

The Dunlops were on a CBR1000RR and I was "carrying the mail"

The Michelins were on a Ducati 999R about 6 seconds off the pace. The first time I had ridden it and I was just trying to get the feel of the thing, sightseeing

Both had the same model tire warmers.

[hubbard_28]

The second set is tearing apart, but that leads me to a question. Aren't performance tires supposed to be "oily?" Isn't that what keeps them peeling like the tires in your pic so it keeps "shedding" loose rubber and maintain traction?

[fossilfuel]

Hub,

What a great question! Look at the two tires again and tell me which one you think would have better traction? I think the Michelin tire is under inflated, to hot and sluffing off to much rubber, actually to slick? The Dunlop is close to its optimum pressure and temperature and adheres better. The rubber is peeling away but at an acceptable rate which doesn't interfere with traction. My educated opinion not anything else.

I was riding a little out of my comfort zone on the Dunlop but I could have pushed it harder. I had no issues with traction period.

What does this have to do with tire warmers? The tire warmers are only part of the equation. Optimum temperature is important but so is pressure.

[Kevin Kane]

Optimum temperature is important but so is pressure.

Fossil;

How do you set your tire pressures? Do you use a cold setting to anticipate what your hot pressures are going to be or do you wait until after your first session to set them?

Since forever, I have been running my Dunlop 208/209 pressures around 30/31 or 30/32 cold but I am now hearing that that is way too firm for a cold pressure.

 

Kevin

[Kevin Kane]

Optimum temperature is important but so is pressure.

Fossil;

How do you set your tire pressures? Do you use a cold setting to anticipate what your hot pressures are going to be or do you wait until after your first session to set them?

Since forever, I have been running my Dunlop 208/209 pressures around 30/31 or 30/32 cold but I am now hearing that that is way too firm for a cold pressure.

 

Kevin

[fossilfuel]

Kevin,

I have just gained enough knowledge in the last year to be dangerous. I have been paying close attention to the way my tire wears after a session and adjusted accordingly. I over fill my tires at the start so I may put 28 to 30 psi cold in the tire and as they get hot with the tire warmers, I bleed the pressure off. It may take me two or three times to do this but I would rather bleed hot air out than add cold air to a hot tire. I then monitor the pressure about two more times to make sure they are stable.

Look at the picture of the Dunlop tire. The tire was wearing more and beading up to the outside more before I added 1.5 psi. That amazed me how the wear and look of the tire changed by just adding 1.5 psi. (this was the pressure I was running for the the 1:38)

Look at the picture of the Michelin. If I were at the track and saw that tire, I would add a little air pressure, check the feel on the track and the wear when I got back to the paddock.

 

Most of this stuff I talk about maybe applicable to your needs or it may be a bunch of rambling ###### but it is what I have observed. When you are in the paddock most information you get is here say. I run this, I heard that, so in so said this, etc, etc. Close observation and twicking your bike and settings to your needs is the best way to learn.

[Hotfoot]

Hotfoot,

Drum roll, please..........................................................................

................. I think, if this is cold tire pressure you are giving me, that you are to hard in the front and to soft in the rear! Don't worry about the blueing thats normal.

This one is Dunlop slick 31 psi hot http://i160.photobucket.com/albums/t172/dt...51/IMG_7439.jpg three track days

This one is Michelin slick 27 psi hot http://i160.photobucket.com/albums/t172/dt...51/IMG_7441.jpg one track day

 

I too was slipping around on the Michelin rear. A 22 psi cold tire would be about 27 to 28 psi hot. I have always seen more wear on the Michelin power race than any other tire I have used.

 

Recommended pressure for the Michelin Power Race from the Michelin distributor at the track is 29 front and 22 rear, cold pressure, which is why I run at those pressures. My tires look like your Dunlop photo, not like the Michelin photo. I would definitely think, if I saw that kind of wear, that something was wrong, it looks like it is melting! The only time I have ever gotten that sort of wear was on my 636 when my rear suspension settings were WAY too hard, on a really hot day, and I overworked the tire so much that it got way too hot and I got streaks and globs like that. I was sliding, because apparently the rubber was melting faster than it was shedding off.

 

I have been running at these same pressures for a long time - both before and after I started using warmers - but the problem of the tires getting slick is new, since I started using the warmers.

[lwarner]

I have Michelin Pilot Powers on my 600rr and the Michelin tech at the track had me run 36 psi front and rear! I was a bit surprised at that and I spoke with him for a bit about the tires... he said that the compound is designed to run at a different temperature from other tires (like the Power One that someone else mentioned) and by running less pressure you are challenging the sidewall integrity as it's not rigid enough to run at a "softer" pressure. Also, and more importantly, at lower pressure you are actually cooking the tire. By adding a few lbs to my tires I noticed a drastic decrease in wear, no difference in traction and a stability that I hadn't realized I had been missing.

[fossilfuel]

Good info! I decided to look at some info on the tire myself since Michelin is not my first choice in tire. Michelin Tire info From Sportbike Track Time

This pretty much agrees with your information.

[Kevin Kane]

...but what about Dunlops? Any 208/209 riders out there who know what the cold and hot temp pressures should be? I have seen my rear tire look alot like Fossil's Michelin photo when I ran them at 30/32 cold.

 

Rainman

[GregGorman]

...but what about Dunlops? Any 208/209 riders out there who know what the cold and hot temp pressures should be? I have seen my rear tire look alot like Fossil's Michelin photo when I ran them at 30/32 cold.

 

Rainman

 

Answers here: http://dunlopracing.com/fitment-2009.html

[GregGorman]

Not an expert in this. It sounds like your one temperature setting is too high. I would reduce the time I have them turned on. I would suggest a procedure like this:

 

Pit, put tire warmers on but off.

At the start of the session prior to yours, turn the tire warmers on.

 

That'll give you about 20 minutes on the warmer.

 

I have chicken hawk warmers with three temperature settings. I run the medium setting for 40 minutes like you're saying, that keeps the tires at ~150 degrees. The High temp is ~170 and the low is 130 something.

 

The reason why it's recommended that the rim get warm too is to retain heat longer when the bikes are gridding up for a race.

[Kevin Kane]

...but what about Dunlops? Any 208/209 riders out there who know what the cold and hot temp pressures should be? I have seen my rear tire look alot like Fossil's Michelin photo when I ran them at 30/32 cold.

 

Rainman

 

Answers here: http://dunlopracing.com/fitment-2009.html

Holy ######! "Sportmax 190/55/ZR-17" - "21 Cold/23 Hot"

 

Greg;

Thanks for posting that here. I've been running overinflated rear tires for a long time. Anxious to see how they will feel with a one-third reduction in air pressure.

Kevin

[Hotfoot]

Not an expert in this. It sounds like your one temperature setting is too high. I would reduce the time I have them turned on. I would suggest a procedure like this:

 

Pit, put tire warmers on but off.

At the start of the session prior to yours, turn the tire warmers on.

 

That'll give you about 20 minutes on the warmer.

 

I have chicken hawk warmers with three temperature settings. I run the medium setting for 40 minutes like you're saying, that keeps the tires at ~150 degrees. The High temp is ~170 and the low is 130 something.

 

The reason why it's recommended that the rim get warm too is to retain heat longer when the bikes are gridding up for a race.

 

Thank you, this is helpful. It seems obvious now, but it had not occurred to me to measure the actual temp the warmers are maintaining. I will check it out. I think I remember hearing that the one setting on them is 180, and relative to your Chicken Hawks, that certainly does sound high. Your suggestion of running them just 20 minutes is a good plan, I'll give that a try, and if keep doing this racing stuff I guess I'll have to get a better set of warmers. My little third place trophy from yesterday is good encouragement to spend more money!

[fossilfuel]

I guess my tires are getting old since they aren't even listed anymore! A nice note at the bottom of the Dunlop fitment page for thise who use tire warmers:

Set Hot PSI after 45 min-1 hr

at 70-75oC (160-165oF)

[GregGorman]

A nice note at the bottom of the Dunlop fitment page for thise who use tire warmers:

Set Hot PSI after 45 min-1 hr

at 70-75oC (160-165oF)

 

 

Yep, that applies to Dunlop tires. I have seen that other manufacturers have different recommendations.

[hubbard_28]

Hub,

What a great question! Look at the two tires again and tell me which one you think would have better traction? I think the Michelin tire is under inflated, to hot and sluffing off to much rubber, actually to slick? The Dunlop is close to its optimum pressure and temperature and adheres better. The rubber is peeling away but at an acceptable rate which doesn't interfere with traction. My educated opinion not anything else.

I was riding a little out of my comfort zone on the Dunlop but I could have pushed it harder. I had no issues with traction period.

What does this have to do with tire warmers? The tire warmers are only part of the equation. Optimum temperature is important but so is pressure.

I was thinking the Michelin was ridden by a rider on an unfamiliar track, or having a bad day. That's what mine look like after one of those days. The Dunlops seem to have scrubbed off the rubber better and/or the rider is smoother. Could also say something about the compound?

Tire warmers heat the tire up more than most can do just riding for heat. As with all rubber, if it's heated more than an equivalent rubber piece and ground on the pavement, wouldn't the heated rubber rub off faster? That's how I figured it was with tires as well.

[fossilfuel]

Hub,

What a great question! Look at the two tires again and tell me which one you think would have better traction? I think the Michelin tire is under inflated, to hot and sluffing off to much rubber, actually to slick? The Dunlop is close to its optimum pressure and temperature and adheres better. The rubber is peeling away but at an acceptable rate which doesn't interfere with traction. My educated opinion not anything else.

I was riding a little out of my comfort zone on the Dunlop but I could have pushed it harder. I had no issues with traction period.

What does this have to do with tire warmers? The tire warmers are only part of the equation. Optimum temperature is important but so is pressure.

I was thinking the Michelin was ridden by a rider on an unfamiliar track, or having a bad day. That's what mine look like after one of those days. The Dunlops seem to have scrubbed off the rubber better and/or the rider is smoother. Could also say something about the compound?

Tire warmers heat the tire up more than most can do just riding for heat. As with all rubber, if it's heated more than an equivalent rubber piece and ground on the pavement, wouldn't the heated rubber rub off faster? That's how I figured it was with tires as well.

"I was thinking the Michelin was ridden by a rider on an unfamiliar track, or having a bad day."

Hub this was the first time I had ridden this bike on the track. The shift lever was not correct and the suspension needs to be set for me. So, I guess you could say I was having issues getting to know the bike.