20230426_000-min.jpg?v=1686213470 PARTS
  • facebook.png
  • twitter.png
  • reddit.png

Tradition and evolution: A look at NOBLEST (AC SANCTUARY)’s fully customized Z900RS and air-cooled Z1

  • facebook.png
  • twitter.png
  • reddit.png
 16 min read

NOBLEST is a shop that excels at Kawasaki customs. They are based in Chiba Prefecture, Japan, with braches of their "SANCTUARY" shops all around the country, and specialize in importing OZ wheels and other products. They are also famous for their "RCM (Radical Construction Manufacture)" fully-completed machines, which are custom-built with serial numbers as proof that no two bikes in the world have the same configuration. NOBLEST has shown that their customs can transcend generations with these two bikes; the Kawasaki Z1 and the Z900RS, one air-cooled and one water-cooled, one old and one new, finished to the perfection that they are known for.

What happens when two Zs from different generations are given the SANCTUARY touch?

As you know, even though they both carry the name of Kawasaki "Z", the Z1 of the 1970s and the Z900RS introduced in 2017 are completely different bikes. The Z1 is a world-class masterpiece that represents Japan, and there's no denying that the Z900RS is a direct evolution that occured through the development of technology, but the only thing they really have in common is their indisputably cool fundamental chassis design. So, what would happen if AC SANCTUARY fully customized these two Zs? Though it could be said that they are somewhat similar, they are actually completely different, and no matter how you look at them, you can see that they are indeniably NOBLEST full customs.


■It looks very beautiful and refined, but you can feel the tremendous power wafting from it because the entire body has been worked on!

RCM-534 Kawasaki Z900RS

This is NOBLEST's answer to the Z900RS. At a glance you can see that it is an intense custom bike loaded with high-quality parts while still maintaining the qualities that make it a "Z". This level of quality customization can only be achieved by NOBLEST! Although there are almost no NOBLEST or SANCTUARY brand logos, this Z900RS is recognizable as a SANCTUARY Z because of it's refined look. Even if you are not a Z900RS owner, you can use this as a model for realizing your own bike's dream. Please take your time to look at the detailed workmanship, which is not merely a result of the use of expensive parts.


■This display bike comes with the serial number "RCM (Radical Construction Manufacture) 534", designating it as a fully customized NOBLEST machine.


■The exhaust is sold by NITRO RACING.
There are 32 different silencer types to choose from, and a special pillion bracket made of machined aluminum is included. The silencer on the display bike is the Grenade Titanium V-III, which is for racing, and the exhaust pipe wraps as closely to the body as possible so that it doesn't touch the ground even when track racing.


■The swingarm is made by SCULPTURE and is longer than stock (swingarm length: 590 mm) in order to emphasize control. The chain adjuster is an adjuster type, while a block type is also available. The displayed bike was equipped with an optional stabilizer, which is available in both hollow and solid types. The wheels are made by OZ, imported and sold by NOBLEST. The rear rim size can be selected from 5.50 and 6.00, and both are priced at 415,800 JPY (tax included).


Available in silver or black, the pedal axle is of course bearing supported. Can be raised up to 35 mm and back 20 mm. The wiring on the silencer joint in case a spring breaks is an ingeneous idea.


■This shot shows how close the step is to the body. The step bar is in a natural position for the rider when getting on the bike.


■The rear suspension is Ohlins.
The hydraulic preload adjuster allows for quick preload changes even when riding pillion. An Ohlins exclusive Preload Adjuster Bracket is also available from NITRO RACING.
■SCULPTURE's "E x M Exmode Package" (768,900 JPY) kit with steering stem and front fender allow for a bolt-on Ohlins inverted front fork (FGRT207) to be installed. OZ wheels, Sunstar brake disc, original floating pins, and a Brembo caliper are also installed.


■The mirror is Magical Racing's NK-1 Mirror TYPE-4


■The headlight brackets are from NITRO RACING and stand out quite a bit.
This is a dress-up part characterized by the fact that it "covers" the stock headlight brackets. In other words, there is a stock headlight bracket in the back, but no matter how you look at it, it looks like machined aluminum!


■The headlight itself is stock. The original workmanship is so good that it looks as if the headlights were customized. This is partly due to the impression created by the steering stem.


Although it looks rough with its bare aluminum exterior, it is actually finished in gun-coated silver (black is also available).
Behind the radiator you can see the Low-mount Pipe Kit, which creates a double cradle style.
This is also available in silver and black.


■The seat was made in collaboration with Daytona.
In addition to the seat being almost parallel to the ground, it is also approximately 15mm lower than stock. The RCM emblem is attached to the seat base, so you can enjoy a glimpse of RCM from this seat alone.


The rear fender eliminator at the tail.


■The tail lenses have been replaced with smoked lenses.


■The RCM logo proudly painted on the top of the tank, visible only to the owner of this complete machine.


■The tank sports a high-quality paint job. The Kawasaki logo looks like it's in 3D even though it's just painted on. Despite the complex paint job, there are almost no bumps in the paint due to the thick clear coat layer.

Kawasaki Z900 (air-cooled)

Air-cooled Z's are also one of NOBLEST's specialties, and they have a special air about them that is a little different from other shops. The customization is the same as other shops in that many expensive and high-end parts are used, but what is unique to SANCTUARY is the use of injection. The reason for using injection is not to increase power, but rather to reduce the carbon concentration that is emitted by these older bike models, in order to support a low-carbon society from a different angle than just the production of EVs. Although power is naturally increased through advanced engine tuning, including the use of twin plugs, it differs greatly from other cases where injection is used, in that power is not the only purpose.

Moreover, it is not just customized for environmental awareness, but the body customization also leaves no stone unturned. It is plain to see that this is a classic SANCTUARY full custom. Let's take a look at this ideal air-cooled Z.


■The injected throttle body seen in the engine intake area stands out, but aside from that, this is an extremely well made full custom air-cooled Z.


■The deep cooling fins, unique to air-cooling, give this engine a powerful appearance. There are two plug cords per cylinder, which shows that it is a twin plug engine.
The beautiful heat colored exhaust pipe is a "4in1 hand-bent titanium EX exhaust" from 277,200 JPY (tax included).


■The "Grenade Titanium Silencer V-3" features a three-piece end. The ends are also welded with thin rings instead of being cut off altogether.


■The rear of the bike is typical of NOBLEST customs. The highly rigid aluminum swingarm, Ohlins twin shocks, Brembo calipers, ultra-thick OZ wheels, and laydown-machined frame all come together for quite an overwhelming sight to behold.


■This is the injected throttle body, which is essential for low emissions. The yellow part inside the funnel is a lid to prevent foreign matter from entering while the bike is on display, so it would be removed before riding. The belt securing the oil line to the frame can be seen in the upper left corner.


The machined backsets are also superbly finished. The master cylinder is a Brembo, but it is unusual to see one that is integrated with the reservoir tank like this. The battery has been relocated to above the swing arm pivot, and it looks like there is a negative pressure valve for secondary air control in front of the battery.


■The front end is equipped with Ohlins upright forks, which are also included in the SCULPTURE "E x M Exmode Package" set. The discs are Sunstar's Works Expand, the wheels are OZ, and the calipers are Brembo monobloc. Just looking at these parts, it is hard to believe that this bike is 50 years old, and it is all thanks to NOBLEST's customization skills that the body structure can withstand these specs.



Webike Japan's global merchandiser who is passionate about motorcycles. Born in Japan, and spent his childhood in the US. 25 years of riding experience mainly on the tarmac and motorcycle market. He loves products made in Japan and considers himself a "Japan Parts evangelist".