Old School, New Limits: KAWASAKI GPZ900R Custom by MARVELOUS ENGINEERING
MARVELOUS ENGINEERING's GPZ900R
There are an abundance of aftermarket parts available for the Kawasaki GPZ900R, the original Ninja, but the first generation was made in 1984 and the bike was introduced in Japan in the year 1990. Over 30 years having passed, the condition of these bikes, particularly used ones, is noticeably deteriorating. The bike introduced here showcases the latest in Ninja customization by Mr. Orime, the representative of Marvelous Engineering, who has created and performs a Ninja maintenance menu that he calls the “Ninja Doc” on these bikes.
"This is the first of two machines I own and am currently working on. I want to try out all the things that look good, and enjoy seeing how far I can go with the Ninja as a base. For example, the upper bracket of the fork is a cut-out version. I wanted to compare the difference in flexibility between it and the stock part. However, the speed needed to make a difference is not something you are going to get up to on the streets. So, I made it more into a machine for the race track. Specifically, I moved the step position back and up, and it is quite tight, giving this Ninja a sharp feel. However, it is a rather pinpoint design and the speed range is high, so it requires a high level of concentration to ride, and that concentration doesn't last very long. So I feel like it is enough to enjoy it once or twice a month,” says Orime.
"The Ninja is a 35 year old bike, but that doesn't mean the original ride is out of date. What's important for customization is to set a clear goal and make sure the base is in good condition, even better if it can be returned to the level it was when brand new. In order to take advantage of the performance of custom parts, the base that they are being attached to should also be at the same level. Ninjas are more modern than you might imagine from the era they were made, but that only applies on the premise of good maintenance. It's nice to enjoy doing some work yourself, but if possible, I'd recommend deciding on a single shop that will work with you and know the bike so that you can have it looked at from a professional's point of view once in a while. If your bike is in good shape, you're going to enjoy it even more.”
Having the condition of the base bike checked by a professional periodically, and having a concrete goal for the intended use and looks; By making sure you've got these two points down, the parts to be used can be determined and the necessary balance can be found. In addition, the necessary budget will also become clear. From looking at Mr. Orime's Ninja, we can see this clear message for the future of Ninja customization.
Handle
One of Orime's "favorite parts of the Ninja” is the cockpit, which makes use of a series of four gauges that are easy to read even when the rider is in a low leaning forward position; the STACK tachometer, an air-fuel ratio monitor that fits into the voltmeter section, and a Q-STARZ lap timer are also mounted. The top bridge is a Mccoy adjustable offset type.
The left and right switches are MotoGP type. They are compact and secure the steering angle without using the stock box type.
Bodyworks
The windshield is a new double-bubble type from Marvelous Engineering that is fitted to the front cowl with a shape that ensures ultra-clear visibility and a high center section that retains the Ninja-like style.
An aluminum inner fuel tank is used, and the tank area now has an FRP cover (both made by SPEEDTEC). The tank was moved forward 10cm at the rear end of the cover, the seat rail was moved forward, and the auxiliary equipment placed there was also moved. According to Mr. Orime, “You now ride on top of the rear shock, increasing the amount of information you get from the rear."
Engine
The Ninja is often equipped with a larger radiator and an oil cooler underneath or in front of it. Mr. Orime also tried various styles of installation and concluded that this front right section was the best. A newly released Dividing Radiator Guard was installed on the radiator to protect the core while maximizing the cooling effect.
This bike has a ZRX1200R (1164cc) engine with a 6-speed transmission for the ZRX1200 DAEG, WPC/DLC/mirror-finished connecting rods, and an ADVANTAGE ST-1.5 cam. The carburetor is a TMR (φ38mm) for better rev at mid-speed and above. For the sliders, ACTIVE's new 2-piece sliders were chosen.
When converting a ZRX1100/1200 or other successor engine for a GPZ900R, the rear hangers can be used as they are, but the front side needs some finagling: the GPZ-R engine can be mounted directly on the cylinder head, but for a ZRX engine that won't work, so a down tube can be attached to mount it.
Mr. Orime recommends changing the ignition system unit to either the Uotani SP2, as used for this bike, or the TG Nakagawa HIR. Even if the appearance of the ignition unit and coil do not change, the insides often deteriorate gradually, causing malfunctions, so it is important to check them.
Chassis
For the front end, it is important to ensure that the fork thickness and tire grip match, and that they are well-maintained and in good working order. This bike is equipped with ø43mm Ohlins RWU forks, monoblock Brembo 4P calipers, SUNTAR discs and GALE SPEED master cylinders, but Orime comments that it is not necessary to go this far for street riding.
The swingarm is by WHEELIE, the wheels are MAGTAN JB4 (3.50-17/6.00-17), and the tires are Dunlop D213GP (120/70ZR17 and 200/60ZR17). The machined steps are by Nitro Racing, and the full titanium 4-1 exhaust is a Marvelous Engineering Conical Goldy that fits the Ninja well.
Gallery
|
|
|
|
|
|
|
|
|
|
|
|
Specifications
About MARVELOUS ENGINEERING
Marvelous in the engineering, without losing the likeness ninja, pursuing the only custom that left the original taste ninja.?In line with this theory, it has conducted the development of the original parts of sticking to taking advantage of the know-how.
MARVELOUS ENGINEERING brand page
Original Source of this Article
Heritage & Legends
editor
Hakuyo
A foreigner who rides in Japan, Japanese call this "Gaijin Rider". Third year in the Webike global team. He feels and shares the real bike life in Japan then presents you how interesting Japanese customs are.
![[New Product] Magical Racing to release additional exterior parts for the GPZ900R! Lineup includes windshields and upper cowls for standard and clip-on handlebars!](https://japan.webike.net/magazine/wp-content/uploads/2024/11/majikarugpz900_13-1024x768.jpg?v=1730783272)
