Tire Pressure/Cold Tires


After sending this message to some of the moderators I recieved some input on posting this message for the rest of the members. So here it goes.

Hey there... It's me again. Something scared me this weekend. I always do my pre riding inspection: oil, tire presure, brake fluid, lights etc. I noticed the tires needed some pressure so I filled them up to 42psi. The temperature was 59 degrees. I went riding w/ some friends and the bike was fine but I noticed that it was sliding a little in the front when I was in the canyons here in Colorado. We stopped for a rest and started riding again back home. On the second turn I noticed my front slid like a half of the lane of pavement at like 50mph. I locked the rear and tried to ride it sideways when I noticed I was not stopping the lean angle but increasing it; I went ahead and put my foot down and up the bike went as the bike went up it shook like a snake and tank slapped. I #### my leathers. I rode the bike w/ alot of calm to the next stop. My buddy who was 10 feet behind me told me good save. We talked w/ a guy who rides in the track here in Colorado and he told me I had too much tire pressure on my tires to lower them a little like to 36psi in the rear and 32 in the front. Also he said the temperature dropped and the tires were cold. My question: What could have caused this to happen? Was it the tire pressure or the cold tires? Maybe both? What tire pressure do you run on when it's cold outside??? Thanks for your response guys and Merry Christmas.
Other information:
Before taking the turn I did the usual downshift, engine brake, look, lean, turn, maintenance throttle, and then accelerate. I'm riding the stock tires. I'm 185lbs. Temperature in that area dropped to 43-45 degrees. RPMS were at like 5k.

Here are some of the response from the guys:

Umm, there is some truth to running slightly lower pressures to improve grip.  Mostly what your doing by lowering pressure is increasing the heating.  Now on a Busa this could be a very bad thing cause you could easily get too much heat in your tires which will increase wear.  So, It may not be too bad of an idea to drop to like 38 front, 40 rear.  Try that first.  DO NOT GO TO LOW, cause all your going to do is muddy up the handling an increase wear.  On the track is one thing, on the streets is another.

Also, if your still running the stock Bridgstones, Loose em.  I recommend the Metzler Sportec M-1's.  Very predictable, better grip, and warm plenty fast.

OH and on REALLY DAMN cold days?  Your tires will have a hard time maintaining their ideal operating temperature regardless of pressure when your just rolling in a straight line.  So just keep in mind, your going to have slightly less grip on REALLY cold days.

My .02

I'm sure you're gonna get different answers and probably more questions from all of us, but to answer your direct question I always ride with 40 psi in both my front and rear. I do agree with folks that ride with slightly more pressure in the rear tire though.
On another note ... I suspect that the traction problems you were having was due to both the tires and the road being cold. It will take a little longer for tires to warm up in the mountains and of course the more pressure in them, the longer it takes. I ride in the WV mountains which are about a 90 minute ride away, but when I stop for lunch, I always swerve the bike agressively to warm the tires up quickly before leaning into the twisties again.
Anyway that was a good save and I'm glad that you kept the rubber side down ... good questions too, because we all should learn from those close calls!

The Oracle:
First...  You should really post this one.  Any answers would be useful for most everyone.  Also, maybe someone else out there has had a similar experience.

On to your question...  Yes, when you hit the rear during a slide on the front, you WILL low-side very quickly.  Your front was probably slipping because it was not warmed properly yet.  Your pressure (42 psi) is fine, but I normally go with 40.  Also, on the track, you run considerably lower, but you sacrifice in ride comfort and tire wear!

The other thing is how old your tire is.  Once they get older and have been through many heat-cycles, they don't grip like they used to.  This is called getting greasy.  It is possible to get greasy before you burn through all of your tread.  It depends upon your riding style, your weight, and other factors like road surfaces and number of heat cycles.

When the front is washing like that, it is normally because you changed the traction for some reason.  Perhaps you thought it might be slipping and then rolled off the throttle a hair.  This is a big no-no...  Rolling off the throttle will shift the weight forward and give a slipping tire even more need for traction!

One thing that you could have done, would be to roll a little (I repeat, "a little") throttle on.  This would transfer your weight a bit to the rear which already had good traction.  This would have been a better choice than the rear brake.  Forget that friggin' rear brake dude!

Stay safe bro!

Thanks to all and Hope it's nice reading...

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sounds like you had to save you own mistake of hitting the rear brake.the front tire slide wasnt gonna hurt ya until you hit the brake!its like riding in the dirt when front slides some stay on it and keep rearend under ya. like flat tracking.
Your stock 56's are great tires. I've chewed the bitter edges off more than one set and I would bet, there is not three guys on this site that can out ride the stock rubber?

Your tires only have two requirements in order to function properly. One, pressure and two, temperature. One, the reason you run 42 psi in your busa tires is for high speed stability, longer life and the tight tire will actually make your busa faster on the top end as well as accelleration. Low tire pressure robs HP but gives better grip. The lower the tire pressure the larger the contact patch and the more heat you can generate. I usually run between 34 and 36 for everyday play. I drop the pressure down if I want to do wheelies or stoppies. When the outside temperature is below 60 degrees you'll never make them really sticky on the streets. What heats the tire for grip is hard accelleration and braking, not necessarily speed. Unless you are cruising at 180 for a half hour on a low tire, you will never heat your tire up with speed. It will get warm but not hot! Don't worry about heat cycles on the street. You will never get your tires hot enough with street riding to go through a heat cycle. Not many guys get them that hot on the track without tire warmers. The proper way to check for proper pressure is to check the cold pressure and after you think they have reached operating temp. check the pressure again. You should have a 3 to 4 pound increase. Once you have this proceedure down, you have optimum tire pressure.

It doesn't take long for a tire to cool down. If you stop for a fifteen minute break, warm up your tires again. Cold tire, cold pavement is a combination that will put you on the seat of your pants. When I take my busa to the track, I run 30 - 30 and it seems to work pretty well. Really hot day, maybe 31 -31. Cold day, drop it down to 28 or 29. When your tires are up to optimum temp. they will actually be HOT to the touch, not just warm. Once you get tires figured out and know what to look for, you can look at the face of the tire and tell what's going on, whether you are running it to cold or to hot or just right. Our tire guy at the track will look at your tire and tell you to add a pound or two or decrease the pressure a little.

The key to riding safely in cold weather is never ride really hard. Your tires are just not going to perform like they do in warm weather. If you do get a little front end slip, DON'T touch either brake. A little throttle will help to decrease the load on the front and hopefully let your front tire grip enough to save you. Your Bridgestone tires are easy to read. They will do just like yours did and slip just a little before giving up. You could have been on Michelins and when the tire slipped, you are on your arse. Just be careful and don't push the envelope. Learn in little baby steps. You don't have to crash to become a good rider. Good Judgment and Common Sense is the key. Enjoy your busa. Ride your Battleax tires with confidence, they are great and you will get pretty good life from them unless you ride really hard. I actually prefer the BT014's over the 56's. I am just about to install my fourth set of 14's and until someone makes something better, I'll continue to use them. I'm sure there are lots of guys who will argue their tire is better, and they very well could be? It's just that I fell in love with the 14's. They give me great confidence in my machine and you won't spend an arm and a leg to buy a set?
I would keep the front tire pressure a little higher than the rear. I usually run 30f and 29r at the track. If the front starts to slide I add a little more throttle. It will make the rear squat and drive the front tire through the slide.

Your tire pressure was def to high for twisties though. Then add cold road and that could have a been a really bad combination. Congrats on the save.
i do some dirt track raceing and the top alcohol guys will have barely warm tires(good, shows great traction).  some guys have really, really hot tires(bad, shows excessive wheel spin).  this from what im told is a result of better traction/set up.

i guess my question is, can a moto be set up so that its tires will not burn up so quickly?  getting to the optimum temp and not over doing it so that you do not over heat the tires(resulting in minimized longevity, i assume). Im not sure much can be applied to street motos but its worth the question.  any insight is very much welcomed, thanks


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I concur with tufbusa.

for high speed straights. keep the pressure at the recommended tire pressure that is listed on the tire.

If you plan on doing a day of mountains / twisties lower the pressure. As was mentioned earlier, the lower the tire pressure, the more area of the tire making contact and the hotter the tire will get increasing traction.

But I would not recommend having low tire pressure that will generate a lot of heat and doing a lot of high speed runs.

Most rides you know before hand what kind of riding you will do for the day, maybe start off with some high speed runs, then before you hit the twisties, pull the bike over, let some air out and using a pressure gauge to make sure you let just the right amount out.

It seems that most sports bike riders end up on twisties more often than a lot of high speed straight runs. I always prefer to stay on the cautious side. I usually run with less air than more air, I usually replace tires when they have another 500 - 1000 miles left on them.

I don’t ride in the rain, nor fog, nor when it is damp out.

And because I live in California, I have the luxuary of not riding when it is below 60 degrees. We have more days above 60 than below.

My riding habits would not suite me well in cold / wet climates such as Colorado, Oregon, Washington. So I don’t envy you folks. And because of where I live and me having the luxury of not riding in inclement weather, my advice is probably worthless to those who live in areas that are cold most of the time.

Ya got to ride sometime or another. I am just glad I don’t have to deal with the crap a lot of you have to deal with.