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ZX-6R ZX636 2007-2025 Cylinder Head Stud Kit by EDR Performance Kawasaki

$ 249.00

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Vendor: EDR Performance

Available: In stock

SKU: STzx6rEDR

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2007-2025 ZX-6R & ZX636 Heavy Duty Cylinder Head Stud kits by EDR Performance

FINALLY A SOLUTION FOR BLOWN HEAD GASKETS ON KAWASAKI ZX6R 636 ENGINES!

EDR Performance is a leader in Performance & Engine Builds with multiple national championships, club championships around the world, HUNDREDS of race wins around the work, multiple track records, Daytona podiums and more. EDR built and tuned ZX6R engines have always been the top placing and highest trap speed 600 in the MotoAmerica/AMA series year after year.

We are pleased to announce our custom HD Cylinder Head Stud kit availability for the ZX6R/636 engines.

We have found the oem cylinder head bolts lack the strength to hold up to big power and high speeds. Not only in the fact it is a bolt, instead of an actual stud and the material is an extremely low quality at best. For the average everyday commuter they are fine, but for those of you out ripping these things HARD, racing them, track-days and such the head gaskets will start to fail! Our custom EDR HD Head stud kit gives you much higher clamping load on the cylinder head so when the pressure is up due to higher heat, more load, higher speeds, more compression and horsepower, your head gasket will hold!

We have found the ZX6R's to be one of the most reliable engines out there, even our 145+ rwhp ones, however the head gasket does take a beating and typically will last only 1 season at best. Now with our stud kit that is a non issue! Also our stud kit has the ability to be used again and again during refreshes, unlike the cheap oem bolts your stock engine uses that are one time use. If you are going to push your ZX6R to the limit, insist on the best, EDR Performance Head Stud kits!

Many of our race builds are running close to and even over 14:1 compression ratio, add this to an engine design that runs very high temps (mainly due to not having a true oil cooler, rather an oil water heat exchanger) the head gasket is THE NUMBER ONE FAILURE ON THE ZX6R! Also many time when you are rebuilding the engine you have to surface the cylinder block, this means you must reuse the oem head bolts and they are really intended for one time use so reusing them in turn will throw off your cylinder head torque. So EDR solved all this with our completely custom HD cylinder head stud/nut kit. Not only do our cylinder head studs/nuts allow for greater cylinder head torque and the ability to contain all the power/heat and pressure. The studs have a recessed allen socket top, this allows your builder or yourself the ability to remove and reinstall several times with zero threat of damage to the threads!

The kit comes complete with all the necessary HD cylinder head studs (10), HD cylinder head 12pt nuts (10) and both outer cylinder head bolts (2.- APR 300 SS for M6 bolts) Also included are detailed install instructions along with the proper recommended thread lubricant as needed. Installation is as easy as the OEM fasteners.

YOU CAN INSTALL WITHOUT REMOVING THE CYLINDER HEAD FULLY!

**MUST CONTACT US FOR DETAILS FIRST**

Key points about head studs:

More even torque distribution:

When tightening a stud, only the threaded section on the nut is twisting, allowing for more consistent pressure across the clamping surface compared to a bolt which twists along its entire length

Better for high-performance engines:

Studs can withstand higher stress and are preferred for modified engines with increased boost or horsepower where head gasket integrity is critical

Easier reassembly:

Since the stud remains stationary, it's easier to align the cylinder head during reassembly.

FITMENT:

2007-2012 ZX6R 599cc

2013-2025 ZX6R 636cc

EDR produced stud kits are EXCULISVELY designed in house at our location by our head engine developer, Eric Dorn. Eric, who in his 30+ years and thousands of race engines has learned one of the most common failures in modern high performance engines is head gasket failures. One of the main reasons is todays OEM's use inferior, cheaply manufactured head bolts.

EDR produced head stud kits only use premium grade 8740 alloy and a proprietary ARP2000® alloy that are rated far superior to “aircraft” quality alloy steels.

Secondly, each stud is placed vertically into special racks and precisely heat-treated to 190,000 psi for the 8740 material and 220,000 psi for the ARP2000® material. This procedure ensures complete heat penetration and the results are far superior to those lesser quality studs from other manufacturers who just dump pieces in a basket and hope for the best.

Following heat-treat, each stud is centerless ground to make it as close to perfectly concentric as possible. This procedure involves about ten very slight cuts and results in an exceptionally straight part. It’s important to note that lesser quality studs are not even centerless ground – the material is thread rolled in bar stock form (mostly before heat-treat, when the material is easier to machine).

Because EDR produced studs are manufactured to such exacting tolerances, you will note that gaskets and cylinder heads literally glide into position and are perfectly aligned – something that won’t happen with inferior quality head studs.

EDR produced studs are thread rolled after heat-treat, which gives them about 2000% (that’s twenty times) better fatigue strength than those studs that are cut/threaded prior to heat-treat (a very common industry practice). It costs a lot more to do it this way, because it’s tough on tooling, but the results are well worth the extra effort.