Why are SLICK street tires so SLICK!?

[gotta240]

I know...dumb question.....but......

Does anyone know why BALD street tires are LESS grippy than they were when they had tread.

The way i look at it.....A bald tire has much more contact patch, and is made of the same material, so shouldn't it grip better IN PERFECT ROAD CONDITIONS. Meaning NO SAND, GRAVEl, WATER, ETC?

Obviously they would suck with roads that are anything less than perfect, but why even on perfect roads does traction with SLICK tires suck?

[mrmephistopheles]

Different compounds of rubber act differently.

The rubber in your pencil eraser isn't the same as the rubber in your tires or the rubber in R-compounds or the rubber in a condom.

Same way eyeglasses aren't made the same as drinking glasses or Pyrex cookware.

[5t341tH]

^good answer

[yudalicious]

actually, from what I gather, tires can have different compounds in layers. But most likely by the time they're worn down to the bars the material is probably heat cycled to death.

[chmercer]

yeah, heat cycling. if you shave a tire you are right it can grip better with less tread.

[smelly240]

and if u cut some reverse camber in the tire - u get even more contact patch ;)

tire cuttin machines are so fun - its like shiny black confetti or silly string.

[gotta240]

Mrmemphis- I'm not asking why my "street slicks" don't work as good as real slicks. Thats like comparing oranges to apples... I'm wondering why the SAME RUBBER that the tread is made out of grips WORSE when there is MORE of it.....


Sounds like the consensus is heat cycling.... Interesting and thanks for the replies.

So theoretically, I could take a set of regular bfg or falken street tires, shave them bald, and they SHOULD have more traction on perfect grounds than they previously did WITH tread...right?

[nsany(atl)]

I think when you get down that far you may be into the bonding material so it sticks to the cords

[Phlip]

Mrmemphis- I'm not asking why my "street slicks" don't work as good as real slicks. Thats like comparing oranges to apples... I'm wondering why the SAME RUBBER that the tread is made out of grips WORSE when there is MORE of it.....


Sounds like the consensus is heat cycling.... Interesting and thanks for the replies.

So theoretically, I could take a set of regular bfg or falken street tires, shave them bald, and they SHOULD have more traction on perfect grounds than they previously did WITH tread...right?
Perhaps you missed:
Different compounds of rubber act differently.

The rubber in your pencil eraser isn't the same as the rubber in your tires or the rubber in R-compounds or the rubber in a condom.

Your tires are harder than traditional "slicks," the rubber was DESIGNED to have tread, and the tread design was in place to assure maximum traction in the conditions that one may expect to find themselves in driving a car on the street.
Wear that tread out, you have exceeded the useful life of that tire by stripping it of the one thing it was designed for.

[gotta240]

I understand that i'm not using it for what it was designed for. I also understand they were DESIGNED to have tread for the "conditions that one may expect to find themselves in driving a car on the street". I'm not surprised they don't work better, i'm just wondering WHY.

I'm not even talking about road conditions...I'm talking about smooth track conditions.

Not, "because they weren't designed for that" type of why, but because after x uses they get so hot they turn rock solid, or another forums reply was because they thought the tread itself actually flexed a lot, reducing the breaking point.

Sorry to beat this to death, but i'm just curious.... So has anyone taken a fully treaded tire and shaved it to a slick? Was the grip better? How long long did the grip last before it felt like a crappy tire made of ice?

Again, thanks for the replies. Its amazing how two different boards come up with 100percent different answers....

[redsuns3838]

not to mention even if you DID shave them down and get more contact patch blah blah, it would burn out super quick even grip racing and if you hit any rain on the street kiss ur ass goodbye

[gotta240]

i know..i'm not trying to do this, i just like to know how/why things work. My 255 rears bald feel like 225 or 215's with tread even on PERFECT surfaces... Just curious as to why...thats all.

so, DOES shaving down a new treated tire(normal tire)=more grip?
if so, how long till it "heat cycles" to death?

[koukimonster139]

i think if you shaved ALL the tread off of a new tire you would have enough rubber left for like a day

[sncs14]

Heat cycling breaks down and reduces the rubbers' properties over time, and street tires are not the same compound as race slicks.

In a lot of instances the reason people shave tires is to reduce tread wiggle not just for straight line traction.

[MrChow]

Can I just ask what kind of tire do you have?

[ep510]

Although R's or slicks do not have a lot of grooves showing like your street tires do --there is usually 2/32 to 4 or 5/32nds of "rubber" still there.

When an R compound DOT approved tire or a true racing slick is worn down to the point your tires are now --they do not grip well either and will slide around like your car is on glass. The Rubber is still what grips the road (or dirt or whatever) ---not having grooves or "tread" just give more contact patch and less opportunity for the tread blocks to move around and overheat the surrounding rubber or chunk off.

the grooves or tread blocks are there to evacuate water, snow, dirt or whatever --different tread patterns for different types of driving environments.

[yudalicious]

Heat cycling, the end. Though to point out something interesting, I've heard that the Falken FM901s' inner layer of rubber is similar compound to the RT215/615 so some autocrossers were buying them new and shaving them instead of buying the RT215/615s. Again, this is hearsay, just thought I throw it out there.

Autocrossers do buy performance tires and shave them, ie kumho mx, to reduce tread squirm.

I understand that i'm not using it for what it was designed for. I also understand they were DESIGNED to have tread for the "conditions that one may expect to find themselves in driving a car on the street". I'm not surprised they don't work better, i'm just wondering WHY.

I'm not even talking about road conditions...I'm talking about smooth track conditions.

Not, "because they weren't designed for that" type of why, but because after x uses they get so hot they turn rock solid, or another forums reply was because they thought the tread itself actually flexed a lot, reducing the breaking point.

Sorry to beat this to death, but i'm just curious.... So has anyone taken a fully treaded tire and shaved it to a slick? Was the grip better? How long long did the grip last before it felt like a crappy tire made of ice?

Again, thanks for the replies. Its amazing how two different boards come up with 100percent different answers....

[turtl631]

I've heard that the Falken FM901s' inner layer of rubber is similar compound to the RT215/615 so some autocrossers were buying them new and shaving them instead of buying the RT215/615s. Again, this is hearsay, just thought I throw it out there

That's odd, since the FM901 is made by dunlop. Industry espionage and compound thievery!

[yudalicious]

That's odd, since the FM901 is made by dunlop. Industry espionage and compound thievery!
lol, you hoe. sorry, eh, what's the other Falken tire, er.. hm... I think it was the FK451...

[gotta240]

shit...i hope its not the FK451!!! THATS THE TIRE I'M ROLLING ON!!!

255, almost no tread left, and i can drift all day long on these....not grippy when slick by any means. (gotta be carefull on my downshifts or unwanted drift is initiated)

[cdlong]

again, shaving tread and wearing tread off are two very different things. your tires are shot, shaved tires just have less tread squirm.

[aznpoopy]

the main purpose of shaving is to control the temperature of the tire. reducing flex in the tire aka tread squirm is a means to an end. less squirm = less heat.

shit...i hope its not the FK451!!! THATS THE TIRE I'M ROLLING ON!!!

a shaved tire and a worn out daily driven tire are two very different things.

tire rubber is not the same throughout it's entire lifetime. every time you drive, the tire gets hot. when you park the car, it cools down again. doing this over and over changes the rubber. hell, tirerack can explain it better than me.

the heat generated every time a tire is driven activates bonding agents in the rubber. As this process is repeated continually throughout the tire's life, its rubber compounds gradually harden and lose flexibility reducing the tire's grip. Therefore, a shaved "new" tire will provide more traction than a tire worn to the exact same tread depth after being driven for thousands of miles on the road.

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=67

[driftenthusiast]

I dont know about shaving normal street tires. Tires like Toyo RA-1's are desinged to be shaved. They have horizontal tread thats pretty shallow, and that is desinged if your running rain or want to use them on the street. Then they have lateral grooves that most people shave then down to if you want to run them on the track.
NEW
http://img207.imageshack.us/img207/6761/ss2mw7.png
Shaved
http://img459.imageshack.us/img459/84/ssco8.png

[gotta240]

Alright, i got it. Thanks guys! That makes perfect sence now.