Suzuki GS550 Cafe Racer: “GS673”

Suzuki GS550 Cafe Racer

1976 was the year Suzuki introduced their first line of four-stroke street machines, the venerable GS series. The Suzuki GS550, which offered 49 horsepower from its air-cooled inline four, was a hard-hitting middleweight, beating both the Honda CB550F and Suzuki’s own GT550 two-stroke in the quarter mile.  With the bike’s light weight, six speed transmission, and surprisingly taut suspension, Cycle magazine would call the bike an “excellent mountain road darter.”

GS550 cafe racer

That sounds like just the recipe for a svelte cafe racer of the old school. Tony Garnham-Parks of the UK’s Complete Cafe Racer set out to create just that, starting with a wrecked ’77 GS550 that hadn’t seen daylight in more than three decades. He punched out the motor to 673cc and fitted fiberglass bodywork designed and manufactured by his company in-house.

Tony gives us the full story on the build below.

The GS673:  In the Builder’s Words


(Words by Tony Garnham-Parks. Highlights by us.)

This bike came to us as a 1977 GS550 that had been crashed damaging the front wheel and tank; it had been put away and stored for 30 odd years which caused the engine to lock up.

We rebuilt the engine and bored the crank cases out to accept the GS650 barrels, pistons, and head, making it a 673cc engine. To feed in the fuel we added a set of GSX-R750 slabby flat slide carbs mounted on GSX-R600 SRAD inlet rubbers.

The exhaust is a Motad 4 into 1, with downpipes modified to fit the 673 head.  The silencer has been removed after the collector allowing a custom-made link pipe to mate up to our GP2 silencer.


The chassis has been modified to accept the GS1000 alloy swinging arm to make room for the 5-inch (160 tyre) spoked rear wheel using a gs1000 hub offset by 6mm away from the sprocket, which is held by a GS750 modified carrier. To get chain clearance we used an offset front sprocket.

The front end conists of a pair of GSX-R750 upside down forks holding the 3-inch spoked wheel (120 tyre), using a GS550 hub with custom spacers holding it central, ‘Busa 6 pot calipers biting down hard onto a pair of fully floating custom discs. The mudguard is mounted on our own custom mounts.

Everything either finished in black powder coat or polished. The fiberglass bodywork is all made in house to our own designs, comprising of our avon-style fairing fitted with twin projector headlights (Ducati 999 style), Rickman tank cover over a custom fuel cell, Rickman-style seat with twin round lights mounted on the back and a CR1 mudguard with the sides removed–all finished in a Ford blue colour with blue and purple flake added, topped off with a couple of coats of candy blue before the numerous layers of lacquer.

Suzuki GS550 Cafe Racer

The electrics are as simple as possible, using a custom loom and only 2 micro switches (keeping the clip-ons clean) operating a relay for high beam and the other for the horn. The lithium ion battery, starter solenoid, relays and fuse box are all under the hump in the seat mounted on an alloy undertray, the rectifier regulator is mounted under the tray so it can keep cool.

Clocks are a single multi function Koso GPS unit. All the work has been done in house, and all these parts are available from our website:

About Complete Cafe Racer


Complete Cafe Racer is based in Sheffield, England, but they ship cafe racer seats and accessories all over the world. Owner Tony Garnham-Parks spent his early career as a salesperson selling motorbike oils before opening up his own businesses, including a stint as a show florist at one point!  He started Complete Cafe Racer Ltd. after needing a cafe racer seat for his own bike, and realizing there were relatively few options and he had the manufacturing and painting experience from his various businesses and jobs to put it all together. Says Tony:

“We aim to provide the biggest range of products with good old fashioned, friendly service. Stop by and say Hi!”

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