One Z to Rule Them All: KAWASAKI KZ1000 Custom by MG NEST

• Z1000
• KZ1000
• Z1

• Share:

• 
• 
• 

MG NEST's KZ1000

This bike belongs to Mr. Shiine of MG Nest, and it’s based on a KZ1000. He uses it for everything from city riding to JD-STER drag races, and even rides it at the Tsukuba Circuit and Ebisu Circuit. How does it manage to handle such a wide range of uses? Let’s take a closer look at the custom work.

"The crank has been balanced at TIS, and the transmission is a 5-speed close-ratio from Three Wave. The pistons are custom-ordered forged JE pistons, 78mm in diameter, bringing the displacement to 1260cc. The cylinder is also upgraded to an APE big block. The head has been shaved by 2mm, the ports are enlarged considerably, and WEB 460/435 cams with a small base circle have been installed. At its best, it produced 148 horsepower. It’s been about five years since the last rebuild, so it’s probably down by about 10 horses now — I’m thinking it’s time to refresh the valve train," says Shiine.

Shiine speaks effortlessly, reflecting the meticulous work that’s gone into this machine. The intake and exhaust are matched to the engine as well, with a Mikuni RS 36mm carburetor and an original megaphone exhaust. An oil cooler has also been added. For drag racing, it’s equipped with a lock-up clutch that increases plate pressure via centrifugal force — but he adjusts the weights so that it remains perfectly usable for city riding too. The ignition system is also upgraded to a PE3 with data logging, allowing him to monitor and control performance changes.

Even though it was running a different engine at the time, this chassis competed in the T.O.T. Monster Class. Up front, it’s equipped with Moriwaki KYB 36mm forks with SS Itoh springs and a modified GPZ900R stem. It is also equipped with 18-inch MAGTAN wheels and a Blue Thunders swingarm at the rear. Together with the engine, it’s easy to imagine how light and agile this bike feels — which makes it clear why MG Nest’s customers would look to it as a reference when building their own machines.

The attention to detail extends beyond performance. The gauge is a STACK all-in-one, while the main key has been relocated to the side of the seat. Shiine even sourced a fuel tank specifically because of its “nicely worn character,” and had Shakin’ SPEED GRAPHIX hand-letter it with a street-style paint job. The mix of old and new technology and aesthetics is perfectly balanced.

Shiine describes himself as an old nostalgic bike enthusiast. Looking at how this KZ1000 captures the way the Z was used back in the day, while incorporating evolved parts and MG Nest’s know-how, it’s easy to see why. But the build is also thoroughly modern, drawing on Shiine’s own experience to reliably extend the Z’s all-around versatility. Including its smart styling, this bike is definitely one to keep in mind as an option for Z customization.

Handlebar

The late-model GPZ900R steering stem, originally for 41mm forks, is fitted with spacers to accommodate the 36mm forks, and the offset was reduced from 60mm to 40mm. The gauge is a STACK ST700SR all-in-one, with indicator lights set into the top bridge.

Bodywork

The tank is a used Z1-R tank (which replaced the original round KZ1000 tank) chosen because it had just the right worn look, although the inside is clean. Hand lettering by Shakin’ SPEED GRAPHICS was added to both sides and the top.

The tail light is a Bates type, and the tiny rear turn signals are ultra-compact LEDs mounted on either side of the license plate bracket.

Engine

The engine uses custom-forged 78mm JE pistons made to order, bringing the displacement to 1260cc. The cylinder is an APE big block. The crank was tuned at TIS, and the transmission is a Three Wave 5-speed close-ratio. The cylinder head has been shaved by 2mm, the ports enlarged, and WEB cams (intake: WEB460; exhaust: WEB435, both with a 1-inch base circle) are used. Since it’s been about five years since it was built, the owner is thinking of refreshing it soon. The front turn signals are mounted on brackets to either side above the 9-inch, 13-row straight oil cooler.

The carburetor is a Mikuni RS36 (RS is the North American name for the TM series) with aluminum intake funnels.

Chassis

The front sprocket cover is made by D&G Chassis and includes an outboard bearing support that holds the output shaft from the outside. The drive chain is an RK 520XXW.

The rearsets combine a base plate from Moriwaki’s Z-series rearsets and an SS Itoh step kit for the Z with bars machined from aluminum. The clutch is a lock-up type from MTC Engineering in the USA, as indicated by the stamping on the cover.

The front forks are stock-diameter Moriwaki KYB 36mm with SS Itoh springs. The front brakes are Brembo axial CNC 4-piston calipers with SUNSTAR Works Expand discs, and the front fender features a flare pattern design.

The rear brake uses a Brembo P2-CR84 2-piston caliper with a SUNSTAR disc. The exhaust is an MG Nest original megaphone exhaust.

The rear shocks are Ohlins KA446 Grand Twin mounted to a Blue Thunders 7N01 aluminum swingarm with a catch tank. The wheels are forged magnesium MAGTAN JB1s, upgraded from the stock 1.85-19 (front) / 2.15-18 (rear) to wider 2.75-18 (front) / 4.50-18 (rear) sizes.

Gallery

Specifications

Part	Details
Engine	JE PISTONS Forged Piston Kit φ78mm (Made to Order) APE Cylinder Block WEB CAM .460 /.435 Camshaft THREE WAVE 5-speed Close-Ratio Transmission R Kit Ver. 2 for Z-1, Z-2, Z1-R
Carb / Intake	MIKUNI RS36 (Equivalent to TM36)
Exhaust	MG NEST Original Megaphone Exhaust
Frame	BLUE THUNDERS Swingarm with Catch Tank and Stand Mount
Brake	brembo PMC Brake Master Cylinder brembo Axial CNC 4-Piston Caliper SUNSTAR WORKS EXPAND Front Disc Rotor brembo P2-CR84 2P Rear Caliper SUNSTAR Custom Rear Disc
Wheels	JB POWER (BITO R&D) [MAGTAN] Forged Magnesium Wheel JB1
Suspension	MORIWAKI KYB Front Fork Kit SPEED SHOP ITO Fork Springs for Current Moriwaki KYB 36mm Forks OHLINS Rear Suspension
Steps	Base Plate from MORIWAKI Rearsets Kit Step Bar / Pedals from SPEED SHOP ITO Rearsets Kit for Z
Drive System	MTC ENGINEERING Multi-Stage Lock-Up Clutch D&G CHASSIS Sprocket Support Kit for Z900 / Z1000 - DragBike Outrigger Plate Kit RK 520XXW Drive Chain
Handlebar / Steering	STACK ST700SR Stack Timer Dash System Base Kit
Oil Cooler	EARL'S Oil Cooler, Straight (9-Inch / 13-Row)

Original Source of this Article

Heritage & Legends