When Continental designers stated that they were working on version II of the famed Grand Prix 4000 S we were concerned that messing with success of this nature could spell trouble. Well as it turned out, it was just a simple cosmetic change. The sidewalls are now offed in color variants with all of the familiar build and handling qualities all remaining the same. There are now 3 sizes to choose from in black - 700x23, 700x25 and 700x28c and three colors to choose from in the 700x23c size. So now you can get a very flat resistant performance tire up to 28c width.
If you have ridden the 4000S then you know it has everything you demand from a tire - rolls fast, very puncture resistant, excellent grip, will not tear or slice. The firm-ish sidewalls do not flex much, so they never pinch tubes due to flex. Now, take all of those attributes and add the fact that they are very light (205 grams for a 700x23mm) and easy to mount and you have a winner by anyone's standards. It is hard to have a conversation about this product without using words like, benchmark and industry standard.
The magic starts with the Black Chili compound. It is derived directly from Moto GP racing and offers lots of high end technology. It is essentially a blend of natural and synthetic rubbers. The natural rubber is mixed with 'nano' sized soot particles, who's surface properties are optimized to deform around surface objects and inconsistencies in the road for better grip. These small particles also form a tighter bond with each other improving compound strength for improved longevity and shear strength. Thanks to these polymers and carbon fillers, the Black Chili ends up being some of the strongest and most durable tread available as well as having the least amount of rolling resistance. The fillers also greatly reduce flatting.
Under the tread, Conti has placed a strip of Vectran which adds to the already out standing puncture resistance. It is essentially a protective belt made of super strong and extremely lightweight and pliant material. Small wear levels indicators have been molded into the tread to measure wear.
The casing is 3 plies of 330tpi material which is flexible enough to give compliant road feel, but stiff enough so it will not flex in corners or under load. This also reduces the chance of pinch flats when run at proper tire pressure.
While designed primarily as a race tire, we have found most riders will use it year round due to the superb durability and extended mileage the 4000 S II offers.