The Ninja Reimagined: KAWASAKI GPZ900R Custom by SANCTUARY

SANCTUARY's GPZ900R

AC Sanctuary is a shop that builds order-made complete customs, which they call RCMs. While they specialize in air-cooled Kawasaki Zs, orders for GPZ-R series bikes, which looks to be their next staple, have been increasing rapidly. What is the reason for this?

"The customers are responding to the circumstances surrounding the GPZ-R Ninja before we even mention it. Specifically, the price of bikes to use as the base has increased, the condition of those bikes has deteriorated considerably on top of that, and stock parts have been discontinued. So it seems like the customers want to take action as soon as possible. We believe that is where our RCMs come in. We procure the base bike and fix it first. Then, parts are selected and modified and the owner gets to test the bike out. With an RCM Ninja they can do all of that in one place. For the RCM Ninja Sports Package TYPE-R that we offer, there used to be brand new bikes or used bikes in excellent condition that we could use for the base. But the condition of the bikes we could get our hands on deteriorated, and in 2015, we had to introduce a new TYPE-R package with a full engine overhaul as a mandatory menu item. In 2018, when the stock pistons were discontinued we prepared oversized forged pistons, and upgraded the front forks to Ohlins RWUs. Aftermarket parts have also changed with the discontinuation of Brembo axial calipers, so we have put them all together to provide the 'New TYPE-R Ver. 2020' menu,” says Mr. Nakamura, the representative of SANCTUARY.

The machine introduced here is the RCM-520, which was built as a demo bike. The engine was completely rebuilt, as Mr. Nakamura mentions above, and the body was optimized to fit the 17-inch front and rear wheels. The front cowl mounts on the front end of the frame were also rebuilt and the frame powder coated. The electrical components were also newly rebuilt from those for a successor model to create the basic style. Then, customization was added to match the owner's needs.

"What I've come to realize when doing this basic work is that the Ninja is now in the same 'vintage' category as the Z. So for customers who choose Ninjas, we want them to be able to ride for a long time, so we look for good bikes, and then build the specifications that they want,” said Nakamura.

The New TYPE-R package, which has been redesigned as mentioned above to offer a build that is of the same quality as a brand new bike, is what Nakamura once advocated; making a discontinued bike into what it would be like if the manufacturer was still producing new ones. This is what keeps the customers coming.

SANCTUARY finds a Ninja and builds it into a base that can be enjoyed, then turns it into a complete custom. Of course, further modifications can also be made from there, and this bike serves as a great example.

Handle

This bike has the Ninja Sports Package TYPE-R Ver. 2020 Start Edition as its base with additional customizations added on. The handlebar is a POSH Faith Super Low Bar and the gauges include a Defi speedometer, STACK tachometer/fuel gauge, and YOSHIMURA PRO-GRESS meter. The mirrors are NK-1 from Magical Racing.

The front brake/clutch master cylinders are Brembo radial CNC and the levers have been changed to ZETA RCM Concept Flight Levers.

Bodyworks

The exterior paintjob based on the A6 design was done by Paint Shop Okushin. For Ninjas, the boss on the frame that attaches the upper cowl bracket is often missing or cracked, so for RCMs this area is welded and reinforced. The frame was also modified to accommodate the wider rear wheel, and powder coated.

The seat is the Daytona RCM Concept COZY Seat. It has been completely redesigned from the base, and the internal foam has been reshaped to improve footing and comfort.

Engine

In the RCM Ninja Sports Package New TYPE-R, the engine is completely disassembled, every part checked, and reassembled with new replacement parts and countermeasures (such as separately chip-cast rocker arms for the A16 and reinforced generator chain for the A8 and later models). The cylinder block undergoes a hydraulic test, forged oversized pistons and new valve guides are installed, seat rings are cut, etc. The crankshaft, transmission, and electrical components are of course also worked on.

Intake & Exhaust

The carburetor is generally replaced with a TMR φ36mm, but optional specifications can be chosen, such as TMR-MJN and the addition of YOSHIMURA dual stack funnels, as with this bike.

The exhaust system consists of a NITRO RACING Titanium Exhaust and Grenade Titanium V-III Silencer, both heat-polished.

Chassis

The frame uses the NITRO RACING Combination Kit, which is made up of a fully machined aluminum monoblock down tube and step base, that reinforces the parts from the front engine hanger to the swingarm pivot, and also brings the frame together in terms of looks.

The front forks are Ohlins New Inverted 21 FF5210BLK, which come in the NITRO RACING Inverted ExM Package along with a SCULPTURE stem, front fender, etc. The front brakes are Brembo CNC GP4-RX calipers + RCM Concept φ320 discs.

The swingarm is a SCULPTURE Wide Swingarm for RCM with monaka structure sway bar, and the rear shock is an Ohlins suspension compatible with 17-inch wheels.

The front and rear wheels are forged aluminum GASS RS-A by O-Z Racing in 3.50-17/5.50-17 inch sizes, and the axle shafts have been increased in diameter from the stock φ17/15 to 25/20mm using those for the ZRX1200. The rear brakes use a Brembo CNC nickel-coated caliper and SUNSTAR φ250mm disc.

Gallery

Specifications

About SANCTUARY

SANCTUARY is a custom builder that is good at Vintage motorcycles like Z1,Ninja and KATANA. They sell special parts which were born from trial and error that mechanics had repeated mounting and testing

SANCTUARY brand page

Original Source of this Article

Heritage & Legends