Redefining Oil-Cooled Customs: SUZUKI GS1200SS Custom by Iida Racing

• GS1200SS

• Share:

• 
• 
• 

Iida Racing's GS1200SS

It has been five years since Iida Racing Factory opened their shop based on Mr. Iida's experience of working on his own GS1200SS. Iida Racing Factory is a place where many owners of oil-cooled models ask for customization and maintenance services. The GS1200SS Custom which Mr. Iida has been working on for more than 20 years since his privateer days is well known as the shop's first demo bike. It was also the base for testing many oil-cooled parts and methods before providing them to customers. As the shop's activities gained more and more attention, Mr. Iida announced that he would build a second GS1200SS demo bike, with a view to participating in the TOT (Taste of Tsukuba) Race. The result is this bike, which was completed earlier than expected. Let us ask Mr. Iida about its current condition and its significance to him.

"This second machine was originally planned to be built as a promotional bike. For the first machine, I did almost everything necessary for an oil-cooled bike, and everything I noticed while riding an oil-cooled bike, and I built it in the style of the YOSHIMURA Suzuka 8-hours Endurance Racer. The second machine also pays homage to the YOSHIMURA Endurance Racer, but it is designed to ride better. It is also designed so that if security parts are removed it can be entered into the TOT as is. Since the first machine was built before I opened my shop, some people said they didn't understand how the actual work and modifications had been done. So with the second machine, we showed the whole production process on our blog and Instagram! We showed the disassembly, frame reinforcement, fabrication of brackets and other one-off parts, and how those parts were fitted. Owners of oil-cooled bikes commented things like 'I didn't know you could do that' or 'So that's how it's done' showing that we got the information across this time. Many of those owners have since come to see the machine at events, and request work and parts. I think that's the biggest significance of this bike," says Iida.

The aforementioned owners of oil-cooled bikes, which have been out of production for some time, making for fewer shops that do maintenance and customization, now have a concrete sense of the work that can be done on their own machines. In that sense, the promotion was a success. Iida and his shop also reaped more benefits than expected.

"For this second machine, we also made it lightweight and heat-resistant. Being lightweight is advantageous in many aspects, including handling, ride feel, and alleviating the burden on various parts. The second machine uses a carbon fiber GS1000R Type Body Kit from CUSTOM FACTORY KATANAKAJI, making the exterior lighter. The frame has a large gusset added under the neck, half pipes added to the lower half of the left and right main frame, and reinforcement around the rear shock mounts. The weight of the bike equipped is about 190kg. The dry weight is 176-177kg, which makes it feel as light as a 400cc class machine. As for the heat measures, the engine is a 1216cc engine, so we wanted to increase the amount of heat dissipation. For this I thought a sub oil cooler would be necessary. The main cooler is stock, and the sub cooler was placed under the front cowl on the first machine, but there was no space for it on the second machine, so we came up with an interesting idea, we decided to place it above the headlight, using the Honda RCB (factory endurance racers from the 1970s to early 1980s) as an example. This lowered the oil temperature by 15℃ compared to without the sub cooler. I also drilled holes in the windshield because the cooler is behind it and I thought it would be necessary to have holes for airflow. It didn't cool enough with 2 rows, so I tried 3 rows with slightly more space between the holes, and it worked well. I think we can make the most of this for future customs,” says Iida.

When reducing weight, the weight itself is not all that's important, it is also important to be aware of the center of gravity to create a balanced machine. A slipper clutch was incorporated into the engine, the weight of the bar ends were considered, and brake pads were chosen with consideration for the distance from the disc. The structure takes into account control and ride feel, and the know-how gained from these efforts will be reflected on customers' bikes in the future. The second machine, which is the embodiment of Mr. Iida's customization philosophy of “a bike that runs, turns, and stops well, is safe to ride, and looks cool,” played a big role as a demo bike and will continue to be used for testing parts in the future. In other words, based on this machine, new ideas for oil-cooled bikes that make them look and run better are sure to come.

Handle

A 4.5-inch x 7-row sub oil cooler is mounted above the headlight, behind the gauges as seen from the rider, decreasing oil temperature by 15°C.

An original mounting panel was created, and the gauges consist of a Stack ST200 Tachometer, YOSHIMURA PRO-GRESS2 Temp Meter, Motogadget Motoscope Mini Speedometer, Motosign Mini, and PLX Air-Fuel Ratio Gauge. Ventilation holes have been drilled in the windshield to provide airflow to the sub oil cooler.

The stem is the Original φ43 Upright Stem Kit made by Iida Racing Factory, which is made of 7075 material and currently available on the market. The cowl/sub oil cooler bracket is a one-off. An OHLINS Steering Damper is also equipped on the front side of the lower fork bracket, and the left and right master cylinders are Brembo CNC Racing.

Bodyworks

The exterior uses the GS1000R Type Body Kit (Carbon) from CUSTOM FACTORY KATANAKAJI, including the aluminum inner tank, with one-off brackets by Iida Racing Factory. The mirrors are Magical Racing Racer Replica Mirrors with Type-3 heads.

The frame is reinforced in three places: an inverted V-shaped gusset is added under the neck, and half pipes are added to the lower half of the main frame (left and right). The seat rail section is newly created, and the seat and fender eliminator are Iida Racing Factory originals.

As you can tell from the choice of exterior kit, the look is based on the YOSHIMURA GS1000R (winner of the Suzuka 8 Hours endurance race in 1980). The turn signals are Kijima NANO ultra-compact LEDs, and the rear turn signals are installed on the left and right sides of the license plate holder as shown in the photo. The front turn signals are installed on both sides of the lower cowl bracket.

Engine

The engine has 1216cc specs with 81mm diameter pistons, which is the same as Iida's first GS1200SS, but this second machine uses Wiseco pistons. The camshafts are YOSHIMURA ST-2, the rocker arms are lightweight GSX-R750RK type, the valve retainers are titanium, a TSS slipper clutch is installed, and the exterior is finished with ceramic coating. The head cover bolts are from the m-tech & B-Titanium Titanium Head Cover Bolt Set.

The intake and exhaust are a combination of a side link TMR-MJN φ40mm carburetor and a one-off titanium ring-cut exhaust. In the upper center of the photo, you can see the half-pipe reinforcement added to the lower side of the frame.

Chassis

The front forks are OHLINS FF521, and the front brakes are Brembo GP4-MS new finned calipers with SUNSTAR Works Expand φ320 discs.

The rear brakes are composed of a Brembo GP2-SS caliper + SUNSTAR Premium Racing φ250 disc. The front and rear wheels are forged aluminum from OZ Racing, GASS RS-A 3.50-17/6.00-17 sizes.

For the rear suspension, a sway bar was added to the lower side of the stock GS1200SS swingarm, and a new stand hook and base set from Iida Racing Factory is attached to the end piece with an OHLINS Grand Twin installed. The drive chain is EK ThreeD.

Gallery

Specifications

Part	Details
Engine	WISECO φ81mm Forged Piston Kit YOSHIMURA Camshaft [ST-2] CUSTOM FACTORY KATANAKAJI TSS Slipper Clutch Kit m-tech & B-TITANIUM Titanium Head Cover Bolt Set
Carb / Intake	YOSHIMURA MIKUNI TMR-MJN40 Carburetor (Side Link)
Frame	YH PRODUCTS Racing Stand Hook Set for GS1200SS/Inazuma1200 MORIWAKI Skid Pad Engine Slider
Brake	brembo Racing Radial CNC Brake Master Cylinder ZETA Pilot Lever, Brake brembo GP4-MS Radial CNC Monoblock 4P Caliper SUNSTAR [WORKS EXPAND] Front Disc Rotor GALE SPEED Rear Brake Master Cylinder brembo GP2-SS CNC 2P Rear Caliper SANCTUARY Rear Caliper Support Kit for 250mm Floating Type Disc SUNSTAR Premium Racing Rear Disc φ250mm
Wheels	OZ Racing GASS RS-A 3.50-17 Front OZ Racing GASS RS-A 6.00-17 Rear
Suspension	OHLINS FF521 Front Forks OHLINS Grand Twin Rear Suspension
Steps	YH PRODUCTS Rearsets Kit for GS1200SS
Drive System	K-FACTORY Front Sprocket Cover K-FACTORY Clutch Release B Type EK ThreeD 520Z (BK;GP) Drive Chain
Handle / Steering	Magical Racing Racer Replica Mirror TYPE-3 ZETA Pilot Lever, Clutch OHLINS Steering Damper STACK ST200 Clubman Tachometer RADICAL Moto Gadget Motoscope Mini Multi Function Meter RADICAL Moto Gadget Motosign Mini YOSHIMURA PRO-GRESS2 Multi-temp Meter
Oil Cooler	YH PRODUCTS Fitting Adapter Set for Oil Cooled Engine Sub Oil Cooler
Bodyworks	CUSTOM FACTORY KATANAKAJI GS1000R Type Body Kit (Carbon) Magical Racing Windshield, Clear Magical Racing Under Cowl YH PRODUCTS GS1200SS Fender Eliminator Kit
Electrical	AS Uotani SPII Full Power Kit KIJIMA NANO Turn Signals

Original Source of this Article

Heritage & Legends