Sporting tire grip & warming question?

[drums4money]

Gentlepeople-

I accept that under track circumstances a tire with a specified compound - hard-med-soft or wet - will be at its' peak grip when full hot and receiving the full brunt of hard acceleration, breaking, and turning.

On the street, however, I question that the grip is more a function of the tire compound, and is a compromise between softness & longevity.  I'm questioning whether a sport rider can ride hard enough, fast enough, for long enough to introduce enough heat to transform the tire traction & attain some mythical "next level" of performance. 

There was an episode of Top Gear a while back where one of the hosts attempted to complete one track circuit in the Renault F1 car.  In addition to the incredible focus required to pilot the thing, he specifically mentioned that he wasn't able to generate the speed and duration required to maintain operating temperature in the tires.  It felt like ice, but the track was dry.

I always take the discussion among sport bike jockeys with a grain of salt when they begin boasting about "getting the tires good and hot so it'll stick in the corners. . ."  I'm tempted to call a flag on the play and ask for proof.  Tire sales = bragging rights, and I can't imagine a manufacturer being willing to downplay the mystique of their performance by relegating it to less technical terms.  I wonder if any of the Keith Code or Kevin Cameron types have ever presented any opinion on grip contrasting street & track.

Soooo . . .on the street with a reputable tire brand, does it truly ultimately boil down to proper inflation, carcass condition, and road surface? 

[oldbike54]

 

 OH MY ! Questioning the incredible riding talents of every squid in existence are you ?  Street tires probably do pick up a bit of grip when warm , and after a few minutes of normal riding are at their peak . But yeah , age , and pavement condition are more important , most street riders aren't fast enough to challenge modern tires .

  Dusty

[redrider]

D- All of the above. I have used a Front "Hybrid" Avon on the Benelli and Sport 1100. A street tire that is also a track day tire. It lasted as long as the rear when a street duty front usually goes 2 for 1. I suspect DOT approved rubber is the best choice for public roads. Track gumballs (soft compounds) work well when used hard but after 100 miles, they are toast. Low pressure causes heat which causes wear which causes wallet deflation. The Canary Islands use volcanic rock as an ingredient in the asphalt. Tires wear quickly there. Hysteresis? Can o' worms. The tires that work well in the summer take a bit longer to feel right in January, if at all. Riding this week with the temps above 100 made for a better feel earlier. Confused yet?

[drums4money]

D- All of the above. . . . Confused yet?

Not confused at all.  Well sorta. . OK- yes.   

[earemike]

On the street, however, I question that the grip is more a function of the tire compound, and is a compromise between softness & longevity.  I'm questioning whether a sport rider can ride hard enough, fast enough, for long enough to introduce enough heat to transform the tire traction & attain some mythical "next level" of performance. 

Soooo . . .on the street with a reputable tire brand, does it truly ultimately boil down to proper inflation, carcass condition, and road surface?

I've been happy with my BT003's but didn't find them quite as grippy as supercorsas on the track. Given the BT003 was designed as a sport tyre for road bikes yet survived well at the track I'd say it was a fantastic compromise. Regarding inflation, running a lower pressure at the track is the norm but even on the road, with higher pressure, I could still feel the heat in the tyres when I stop. That's one of the things I check when trying different tyres or pressures, if the rubber is cold it's overinflated.

When I've run sport-touring tyres I've found the grip to be lacking & think that's from the harder compound which extends life. I used to hit a particular bump that set the harder tyres sliding where the softer tyres did not. Same bump, week after week for months.

Thus I hypothesize that tyre grip is a function of compound and the level of wear/grip can be mildly adjusted through tyre pressure all other things being equal.

What has surprised me is the level of grip from the pirelli sport demons on my '77, those cross plys are pretty good!

[Murray]

The Evolution of tyres has got pretty good over the years and most sporting tyres see duty on machine that are lighter with a hell of a lot more power than a crummy old Guzzi will ever make. Anecdotally the track oriented sports tyres/production racing tyres can be cold blooded on a cold morning first thing. Generally however it only takes about the first 10mins of riding to get some temperature into them. They are no however as narrowly focused as full racing slicks which won't work when cold and why tyre warmers exist.

15 odd years ago I used to run a sports tyre on the rear and a production race compound on the front of an 1100 sport now for similar performance a set of sport touring tyres off the same company gives a good result. Basically Tyres are pretty good nowadays providing you are not stupid about it.