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F1
December 20th, 2001, 08:29 PM
Can someone explain the mechanics of tire warm up (how good is the conduction coefficient). Does riding in a straight line (normal riding on streets) for a mile or 2 enough to warm up the entire surface of the tire?

Or is riding in S's necessary to warm up the the edges of the tire?

So the question could also be put as, the center contact area gets warm due to friction with the road, does the rubber compound have enough conduction to warm up the edges too?

Faisal ZX-6R

[ December 20, 2001: Message edited by: Faisal ]

Michael
December 20th, 2001, 08:56 PM
Some information here...
http://venus.13x.com/roadracingworld/index.html

Michael
December 20th, 2001, 09:03 PM
one more time--taken from RoadracingWorld.com
http://venus.13x.com/roadracingworld/issues/feb00/weave.htm

F1
December 20th, 2001, 09:13 PM
Wow, an eye opener. The data shows:

1: Weaving causes accidents not tire warm up.
2: Sunlight causes tire warm up.
3: Tire warmers cause tire warm up (the best).
4: Regular warm up lap causes tire warm up.

Doh, a lot of members weave before hitting the twisties and I followed the legacy!

Data shows that without warmers best way is to take a hot lap, does getting to the twisties equals a "hot lap" on the street, guess not. So the deduction could be to ride regular to the twisties and start leaning with caution before going double+ in the corners?

We should talk more about this, a total contradiction to popular belief!

Faisal ZX-6R

[ December 20, 2001: Message edited by: Faisal ]

bvia
December 20th, 2001, 10:38 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:
Doh, a lot of members weave before hitting the twisties and I followed the legacy!
We should talk more about this, a total contradiction to popular belief!

Faisal ZX-6R

[ December 20, 2001: Message edited by: Faisal ]<HR></BLOCKQUOTE>

The best way to heat up a tire, on the street, is to ride while trail braking. This causes the friction between the tire and road surface to rise and that in turn heats up the tire. The reason I weave before hitting the twisties is three fold.

1. To scrub any road grime the tires may have picked up on the way to the twisties off.

2. A quick last minute check of the tire pressures and the bike's overall fitness to hit the twisties.

3. And last but not least, phychological. That last minute weaving gets me in the correct frame of mind.

As an aside it also shows the newer riders that we are about to hit the twisties...plus it makes my *** look smaller ;)&gt;

Streetbike's aren't race cars with slicks. Weaving won't heat up the tires an appreciable amount.
hth,
bill

dcanovali
December 20th, 2001, 11:18 PM
Bill,

While I agree about 1 and 2, are you sure about #3 :eek: :eek: :D

dcanovali
December 20th, 2001, 11:19 PM
OOPs, I mean the 4th statement :rolleyes:

Jeff Roberts
December 21st, 2001, 06:46 AM
I'm really glad you brought this up. I'm heading for Arkansas tomorrow - Christmas with the wife's family and I will be hauling my bike along with us. I've been watching their weather with great interest, forecasted highs will be in the forties. While that in and of itself will be a ***** I've had concerns about the tires. I've really pondered what the effects of 40+ degree temperatures have on tires and whether they will truly ever come up to temp with that kind of cold air blowing on them at 40-100 mph? With a wind chill, that's like sticking your tires in the freezer. I know flexing and friction builds heat in a tire but it's all guessing game.

Before your post my plan was to take it easy, riding for about 15 or 20 minutes (in twisties - BTW they start at the end of the driveway) pull my glove off and check them. I then anticipated repeating this simple process so that I had some sort of odd baseline and adjust accordingly. I've ridden in Arkansas many times before but I usually take my boat during Christmas and fish this time of year. I think this will be the first time I've ridden these roads at these temperatures during Christmas.

The other good news is that my rear tire is brand new, I don't think it has 200 miles on it yet.

jr

Hood Ornament
December 21st, 2001, 08:48 AM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Dale Canovali:
OOPs, I mean the 4th statement :rolleyes:<HR></BLOCKQUOTE>

Are you in the habit of looking at Bill's ***? :eek: :D

Brett
December 21st, 2001, 10:41 AM
I remember reading an article in one of the sport rags written by a guy from Dunlop. He was talking about warming up tires and the theory of weaving.

The Dunlop guys response was that weaving was a waste of time. However, he did say the best way to warm up your tires is by hard acceleration and hard braking. He said that one way to really warm up a tires is to flex the carcus, and the best way to do that is by hard acceleration on the rear tire and hard braking on the front tire.

So, you DFW guys should be in good shape! "OK, out of the corner, time to pick up the pace &lt;insert hard acceleration&gt;. Uh oh, the road curves ahead! &lt;insert hard braking&gt;"

Happy holidays you guys!

bvia
December 21st, 2001, 02:03 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Dale Canovali:
OOPs, I mean the 4th statement :rolleyes:<HR></BLOCKQUOTE>

I was only going by what you said the last time you were riding behind me...;)&gt;
bill

bvia
December 21st, 2001, 02:10 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Jeff Roberts:
I'm really glad you brought this up. I'm heading for Arkansas tomorrow - Christmas with the wife's family and I will be hauling my bike along with us. I've been watching their weather with great interest, forecasted highs will be in the forties. While that in and of itself will be a ***** I've had concerns about the tires. I've really pondered what the effects of 40+ degree temperatures have on tires and whether they will truly ever come up to temp with that kind of cold air blowing on them at 40-100 mph? With a wind chill, that's like sticking your tires in the freezer. I know flexing and friction builds heat in a tire but it's all guessing game.

Before your post my plan was to take it easy, riding for about 15 or 20 minutes (in twisties - BTW they start at the end of the driveway) pull my glove off and check them. I then anticipated repeating this simple process so that I had some sort of odd baseline and adjust accordingly. I've ridden in Arkansas many times before but I usually take my boat during Christmas and fish this time of year. I think this will be the first time I've ridden these roads at these temperatures during Christmas.

The other good news is that my rear tire is brand new, I don't think it has 200 miles on it yet.

jr<HR></BLOCKQUOTE>

The first problem with your plan is that you will never be able to tell anything by using the "pull glove off and check them" method. By the time you stop, pull off you glove and feel them they will have lost any heat you put in them and they will always feel cold.

Problem two is that your rear tire isn't broken in yet. Yes, you've got 200 miles on them, but you also need heat cycles to break in a street tire.

I'd try trail braking for a few miles, weaving to see how they feel and then progressively wick it up until you find your cornering limit. Also if you're planning on doing Talihena, watch those long straights up on the top. It might give the tires a chance to cool down...a little trailbraking couldn't hurt on those straights.

Take it all with a grain of salt, YMMV, etc, yaddayaddayadda...
bill

bvia
December 21st, 2001, 02:13 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Hood Ornament- Albert to the tardos:


Are you in the habit of looking at Bill's ***? :eek: :D<HR></BLOCKQUOTE>

Don't get jealous, sweetie...there's enough to go around. ROTFLMAO...;)&gt;
bill

bvia
December 21st, 2001, 02:16 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Brett:
So, you DFW guys should be in good shape! "OK, out of the corner, time to pick up the pace &lt;insert hard acceleration&gt;. Uh oh, the road curves ahead! &lt;insert hard braking&gt;"

Happy holidays you guys!<HR></BLOCKQUOTE>

We would never use the patented "Brett Murdock Full Tilt Race Pace" on the street...;)&gt;
bill

F1
December 21st, 2001, 05:41 PM
Well the hard acceleration and braking works, just came back from a mini cemetary. Tried to find the traction limit by getting on the gas early a few times and sure enough the back came around once, the next corner the front slipped mid corner just as I hit the gas a lil too hard maybe(thought the front would remain planted!).

Next couple o miles tried the accel/brake method and the bike felt more planted on the same corners, same speed. Got a lil scared when the front slipped though, glad to be home!

Faisal ZX-6R

bvia
December 21st, 2001, 05:49 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:
Well the hard acceleration and braking works, just came back from a mini cemetary. Tried to find the traction limit by getting on the gas early a few times and sure enough the back came around once, the next corner the front slipped mid corner just as I hit the gas a lil too hard maybe(thought the front would remain planted!).

Next couple o miles tried the accel/brake method and the bike felt more planted on the same corners, same speed. Got a lil scared when the front slipped though, glad to be home!

Faisal ZX-6R<HR></BLOCKQUOTE>

Trailbraking the rear will flex the carcass just as much as hard acceleration will, possibly more so and quicker.
bill

F1
December 21st, 2001, 06:29 PM
Bill,

Define your trailbraking technique. Is it riding with the brake on? or just hit the rear brak a few times? in corners?

Faisal ZX-6R

bvia
December 21st, 2001, 06:55 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:
Bill,

Define your trailbraking technique. Is it riding with the brake on? or just hit the rear brak a few times? in corners?

Faisal ZX-6R<HR></BLOCKQUOTE>

Trailbraking is the two wheeled equivalent of "riding the brakes" on a car. In this context you simply ride in a straight line, accelerating and apply the front or rear brake. Keep both the brakes and the gas on until the bike slows way down, release the brakes, speed up and do it again. Don't jump on the brakes, do it gradually. This will flex the carcass and that creates the friction which causes the heating of the tire.

You can also trailbrake when you've gotten into a corner too hot. This should be used as a last resort because you're trading cornering grip for braking grip...
bill

Michael
December 21st, 2001, 06:57 PM
I've always taken trail braking as feathering the brakes (front and rear) off as you lean it in, something I'll do on the track if I'm trying to get around someone--but on the street, and as a method of warming up cold tires? hmmm.

F1
December 21st, 2001, 07:13 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by bill via:


Trailbraking is the two wheeled equivalent of "riding the brakes" on a car. In this context you simply ride in a straight line, accelerating and apply the front or rear brake. Keep both the brakes and the gas on until the bike slows way down, release the brakes, speed up and do it again. Don't jump on the brakes, do it gradually. This will flex the carcass and that creates the friction which causes the heating of the tire.

You can also trailbrake when you've gotten into a corner too hot. This should be used as a last resort because you're trading cornering grip for braking grip...
bill<HR></BLOCKQUOTE>

Now I'm confused, what is the purpose of keepng the gas on while braking? would'nt it just cause wear n tear of the pistons/rods/crank, the brake and the chain? The brakes and the motor are opposing forces in this scenario, the tire carcass would see the same distortion when brakes are applied while gas is let off, would'nt it


:confused:

Faisal ZX-6R

[ December 21, 2001: Message edited by: Faisal ]

Weave
December 21st, 2001, 07:45 PM
The brakes may suffer a bit more wear while trail braking, but I would think nothing too detrimental, as the braking action results in the pads rather lightly touching the discs, versus a pulling a "stoppy".

Also, the chain will have less force on it during trail braking than under a hard acceleration. I think Bill's example is to create a small amount of additional tension on the rubber. We undoubtedly create more tension during hard cornering and accelertion. The trail braking allows us to warm the tires under more controlled circumstance.

Weather on Monday looks c-c-c-cold. Who's up for a ride tomorrow (high of 62)?

bvia
December 21st, 2001, 07:48 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:


Now I'm confused, what is the purpose of keeping the gas on while braking? wouldn't it just cause wear n tear of the pistons/rods/crank, the brake and the chain? The brakes and the motor are opposing forces in this scenario, the tire carcass would see the same distortion when brakes are applied while gas is let off, would'nt it


:confused:

Faisal ZX-6R

[ December 21, 2001: Message edited by: Faisal ]<HR></BLOCKQUOTE>

Keeping the throttle working against the brakes allows me to bring the tires up quicker than accelerating/decellerating and it keeps me from stringing out the group due to the yo-yo effect. This also allows the rotors and pads to warm up. Wear and tear is negligible (but there is some) when using my method and only you can decide which is best. Trial and error and everyone's different. This method works for me, it might not for everyone/anyone else!
bill

F1
December 21st, 2001, 09:08 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by bill via:


Keeping the throttle working against the brakes allows me to bring the tires up quicker than accelerating/decellerating and it keeps me from stringing out the group due to the yo-yo effect. This also allows the rotors and pads to warm up. Wear and tear is negligible (but there is some) when using my method and only you can decide which is best. Trial and error and everyone's different. This method works for me, it might not for everyone/anyone else!
bill<HR></BLOCKQUOTE>

Even modern science cant explain why placebos work but they do. Maybe I'm missing something but braking with open throttle will warm up the pads n rotors no doubt, but hows does it translate to distorting the tire escapes me! I mean in this case the poor hub is under tension, how will it increase the friction between the tire n the road! Like I said, I'm missing something big.

Faisal ZX-6R

[ December 21, 2001: Message edited by: Faisal ]

Hood Ornament
December 21st, 2001, 09:57 PM
**** Faisal, just ride the **** thing, if the tires start slipping, slow down. :rolleyes:

F1
December 21st, 2001, 10:04 PM
[QUOTE]Originally posted by Hood Ornament- Albert to the tardos:
**** Faisal, just ride the **** thing, if the tires start slipping, slow down. :rolleyes:[/QUOTE

Works for me Albie, no more stupid questions.

Faisal ZX-6R

bvia
December 22nd, 2001, 12:07 AM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:


Even modern science cant explain why placebos work but they do. Maybe I'm missing something but braking with open throttle will warm up the pads n rotors no doubt, but hows does it translate to distorting the tire escapes me! I mean in this case the poor hub is under tension, how will it increase the friction between the tire n the road! Like I said, I'm missing something big.

Faisal ZX-6R

[ December 21, 2001: Message edited by: Faisal ]<HR></BLOCKQUOTE>

Like I said, maybe I'm wrong...maybe this IS just a placebo, but it's always worked for me.

I could go into the theory of a disc rotor brake system and it's inherent built-in modulation frequency and how that translates to the tire's carcass or the loading and unloading of the rubber crush drive in the hub or the tension variances in the rotating chain, but i wont. I'm not an engineer, you are...;)&gt; My point was that you don't need hard acceleration to heat up your rear tire.

All I can say is that I've never had a tire slide out because of cold weather before.
Sorry my science is lacking.
Bill

[ December 22, 2001: Message edited by: bill via ]

F1
December 22nd, 2001, 09:15 AM
Bill,

It's highly unlikely that you are wrong, if it works for you then there is definitely something behind it.

Faisal ZX-6R

Hood Ornament
December 23rd, 2001, 09:00 AM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Faisal:
[QUOTE]Originally posted by Hood Ornament- Albert to the tardos:
**** Faisal, just ride the **** thing, if the tires start slipping, slow down. :rolleyes:[/QUOTE

Works for me Albie, no more stupid questions.

Faisal ZX-6R<HR></BLOCKQUOTE>

Faisal,
There are NO stupid questions. But there is a point where you over-analyse something to the point where it's meaningless. Riding a motorcycle is an experience, not a science project. :D

Now go have fun.

Jeff Roberts
December 31st, 2001, 02:46 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by bill via:


The first problem with your plan is that you will never be able to tell anything by using the "pull glove off and check them" method. By the time you stop, pull off you glove and feel them they will have lost any heat you put in them and they will always feel cold.

Problem two is that your rear tire isn't broken in yet. Yes, you've got 200 miles on them, but you also need heat cycles to break in a street tire.

I'd try trail braking for a few miles, weaving to see how they feel and then progressively wick it up until you find your cornering limit. Also if you're planning on doing Talihena, watch those long straights up on the top. It might give the tires a chance to cool down...a little trailbraking couldn't hurt on those straights.

Take it all with a grain of salt, YMMV, etc, yaddayaddayadda...
bill<HR></BLOCKQUOTE>


Well, you're probably right but I did it anyway just to see what would happen. Temps were upper 30's to lower 40's. Just riding easy then picking it up for a bit did warm the tires to the touch. What did surprise me was how quickly they cooled. Once I stopped, sucked down a quick smoke and felt them again they were almost ice cold....maybe 5 minutes.

The sun definitely heats them nicely, only had one afternoon to try this test.

The whole time I was there I never had a lot of confidence in my back tire which validates your heat-cycle comments. Back in TX this Saturday my wife and I went for a ride 2 up, I think it was upper 50's. In a couple of turns we found the edge that still had the shine on it. It slipped but still felt in control, not like the colder temps with less lean angle.....for what it's worth.

jr