When reading reviews or technical copy about Michelin Pro series tires, it has become standard bike industry trope to sell the tire on its history. After all, Michelin created the high performance clincher tire and changed the industry. Not that this isn't factual and a piece of history, but it's not that relevant some 25 years later. What is relevant, is how Michelin has taken their MotoGP technology (which they have spent millions developing) and trickled it down to the Pro4 race tires. This is an industry first and unlikely to be followed, due to the fact that Michelin is currently the only manufacturer to engineer tires for both the MotoGP motorcycle and F1 car racing circuits. Massive resources are what Michelin brings to the table and the returns are big to riders using the Pro4 Service Course tire.
To understand the Pro4 and where it came from, Michelin took the venerable Pro3 and split it into four versions: the Pro4 Endurance, the Pro4 Service Course(what you see here), the Pro4 Comp Service Course and the Pro4 Comp Ltd Edition Service Course. These are listed in order by longest wearing first/best performing last. The Pro4 Service Course is the closest descendent of the Pro3 with better cornering capacity, longer wearing and lower rolling resistance being some of the improvements.
Although sharing the same casing as the Pro3, the improved tread compound increases mileage a whopping 30-50%. The profile of the compound has changed as well. Michelin states that it is sharper. Meaning, the angle from the shoulder of the tread to the center of the tread is steeper. This idea came directly from MotoGP and is said to accomplish two things: get the tire into the lean angle quicker and then offer a larger contact path therefore increasing grip by 13%. It's all about the angle.
This improved compound tread is applied to Michelin's ESC (Extra Supple Casing) 110 tpi casing. This highly flexible, cross-ply casing is dense and durable, but is also very compliant giving the tire a very smooth feel on the road. There is a thin layer of rubber coating on the sidewall for added protection. Under the tread is an HDPP (High Density Puncture Protector) protective strip which guards the casing from road debris and reduces the chance of flatting.
In summary, Michelin took a solid design with the Pro3 and improved it in many areas to provide riders with a better performing and more durable product. If you liked the Pro3, you will undoubtedly love the Pro4 Service Course.