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View Full Version : Tread? We Don't Need No Stinkin' Tread?!!!


Desmo Demon
10-27-2009, 09:48 PM
The last two weekends I've ridden the ST2 it's had a tendency to slide a little when I was trying to push it a little, so I've just been taking it easier than usual. Well, I think I've finally come to the conclusion that the front tire is toast. Looking at the hint of lines in the bald section, it looks like the cords were pretty close to showing.

http://i32.photobucket.com/albums/d32/Kramer_Krazy/slick_as_snot.jpg

I've always disliked running the Pirelli Supercorsas. The minimal tread just shinks as the slick section grows. I really wish Pirelli would put some wear dots on the tires, like what is on racing slicks, so it would be easier to tell when they are getting worn. I guess I got my $10 out of this single-session take-off.

Justin
10-28-2009, 07:52 AM
Trade ya??? :tease:

This one is from about 11k of mostly supersslab.

http://lh5.ggpht.com/_Kkixd42mCfk/Snc3YsXPvkI/AAAAAAAANyU/YvV_cgJH6L4/s800/IMG_3450.JPG

rodm850g
10-28-2009, 11:35 AM
Alright,
Home made slicks......
Rod

RockerSE
11-15-2009, 06:34 AM
While the contact surface area does go up on a slick tire, the loss of grip is substantial as the tread gets thin as it looses its ability to conform to the road surface.

Alas, I am a tire nerd. I have worked with Jaguar, Renault and Red Bull F1 teams, Pratt & Miller factory Corvette team, numerous stock car series and even a couple of import drag racers and have about 30 years in the industry. I am currently working as a part timer in off road truck racing as a tire nerd.

buddyholly
11-15-2009, 07:19 AM
We used Steve Cole from the Vette team to help us dial in an SCCA GT-3 car running GY 23x11x15 (?) bias plys...he helped us a lot...did you meet him?

Viper
11-15-2009, 07:47 AM
That looks like my front tire on the FJR right now. Only 4000 miles and the only tread I have left is in the center of the tire. I guess these heavier sport touring bikes are a little harder on tires than the light weight speed rockets.:lotsofcoffee:

RockerSE
11-15-2009, 10:12 AM
We used Steve Cole from the Vette team to help us dial in an SCCA GT-3 car running GY 23x11x15 (?) bias plys...he helped us a lot...did you meet him?

Yep, spent alot of weekends with Steve. I hear he is no longer there.

buddyholly
11-15-2009, 03:45 PM
Yes, it appears the world of motorsport is imploding...I have many friends who are out of work...so much of it is pseudo spec-racing now...not too much to tweak when everything is painted shut. Besides that, most everyone is holding any expendable income close to the hip...our team only ran 1x at Road Atlanta, 3X at Elkhart...we used to run at least 6x per year...SAD.

mikek
11-15-2009, 09:16 PM
I did a ride last week with a bunch of old farts on BMW's

here is my rear SuperCorsa when I got back to my shop.

Desmo Demon
11-16-2009, 07:06 AM
While the contact surface area does go up on a slick tire, the loss of grip is substantial as the tread gets thin as it looses its ability to conform to the road surface.

Doesn't this statement go against all purposes that they use slicks in many types of racing? I mean, if this truly was correct, wouldn't they rather have tread instead of slicks on dragsters, Indy cars and Moto GP? :scratch: I could see this being true, to a certain degree, if the contact patch was several square inches, like on a 10" wide auto racing tire, but a motorcycle tire has a tiny contact surface area compared to a car tire. I have heard of rally racers taking new tires and shaving half of the tread off because of too much tire flex.

The largest reason given to me by employees from Michelin for tire slipping once they go bald is that often when going beyond the wear bars and definitely slick and close to the cords, you get into the carcus rubber; a different rubber compound, and usually harder, than the rubber used for the tread. With the Dunlop D220 rear tires my wife has run through, we've noticed a difference in the color of the rubber as she got into the carcus. If you look at the grooving in the first picture above, the cords are very near the surface, so chances are, I was no longer riding on the softer rubber that was used for the tread.

I did a ride last week with a bunch of old farts on BMW's

here is my rear SuperCorsa when I got back to my shop.
That really does look like a slick! :dance3:

RockerSE
11-16-2009, 03:51 PM
Forget about tread other than it's an indicator of how thick the remaing tread is.

The thicker the tread (slick or grooved), the more conformant the rubber will be to the surface providing more grip (same as closer to the cords creating les grip). In essence it acts like a softer compound. But of course there are trade-offs, change of direction will not be as crisp etc.

As you stated, if you go through the tread compound into the underlying compounds, you have lost all hope of grip and may soon have what we refer to in motorsports as a "boom smack".

STRETCH
12-30-2009, 05:10 PM
I don't feel like I got my moneys worth out of this one:headshake:
I hate waisting tread but those pesky cords were starting to poke through

C.R.S.
12-30-2009, 06:57 PM
I don't feel like I got my moneys worth out of this one:headshake:
I hate waisting tread but those pesky cords were starting to poke through

Is that your FullBore Front Tire? How Many Miles?

STRETCH
12-30-2009, 07:17 PM
actualy it's the Shinko Raven rear, wich incidently lasted nearly twice as long as the Full bore front tire.

Desmo Demon
12-30-2009, 09:46 PM
Is that your FullBore Front Tire? How Many Miles?
I have no problems seeing cords on the rear tire, but the front tire starts getting really slippery when you get down into the carcus and the harder rubber compound. A sliding rear tire is usaually a bit easier to recover from....reminds me of my days riding dirt bikes....many, many years ago.

I miss my old Husqvarna dirtbikes, but it's a PITFA ass to go dirt riding these days....nothing like riding 1/4 mile down the road and then being in restrictionless miles of state property like it was in Manchester State Forest in the 80's. I miss those days. No dirt road, fire-break, or trail was off limits. It was nothing like the three, one-way, 9-mile loops that they have now. Back then, I could ride for 120+ miles and never hit the same section of road or trail twice....and no permit was required.

bandit01
01-24-2010, 11:32 AM
Those days are just about gone...

I hear that riding next to railroad tracks is a good way to get out, but you have to deal with private land-owners.

STRETCH
01-25-2010, 04:16 PM
I only got 1,000 miles out of this Maxxis rear.
sides went smooth after just 2 weekend rides.

STRETCH
01-25-2010, 04:17 PM
still plenty of tread left in the center