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Kawasaki Z650 Flat Track Custom

This bike has gone to a new home now, but still holds a special place for me. It was a long project. I took an iconic but rusty old 1977 series 1 Kawasaki Z650, and transformed it into a bit of a monster.

Kawasaki Z650
Kawasaki Z650 Custom

Definitely one of my more radical builds. I tried to keep the essence of the Ken Inamura design but take it a stage or two further. Not a show bike, or a complete renovation, it was built to ride and was a joy to own. It is something special and VERY individual

Kawasaki Z650

It was a rough but running Kawasaki Z650 when I got it. I went over it checking and servicing everything as I went. Then it was modified, tidied up and anything necessary rebuilt. The major modification work was the suspension.


The rear suspension is now a monoshock, with a polished gsxr swingarm. It sits on a fully adjustable showa shock, so the bike is longer and lower than it was standard. Front end is B1 but with an oversize twin disc conversion. Stantions were dropped in the yokes and slightly stiffer springs fitted with twin, oversize sunstar disks off a Kawasaki Z750. Fork legs were polished and reversed so the callipers fitted right on the larger discs and braided lines fitted.

twin disc front

Front brake callipers were kept original but completely rebuilt. They were polished inside and out, with new stainless pistons, new seals and bleed nipples. This meant overall, it turned in faster stopped much better and had great straight line stability. The changes to geometry meant it dived eagerly into corners and was a joy to ride. I know it will have brought many miles of joy to its new owner just as it did me.

Kawasaki Z650 headers

One Glorious Kawasaki Z650 Engine

The glorious engine was compression tested with valves adjusted. It starts straight away even on coldest days. Tick over is clean and steady. Pick up is fast with no flat spots and you get a glorious sound from the 4 bell mouths. This complements the sound of the exhaust perfectly. The Custom 4 into 1 stainless headers lead into a hand-made custom Pea-shooter exhaust.

bell mouths

Spun steel bell mouths with a stainless filter were fitted to allow me to tune the engine more. Carbs were fully cleaned repaired, re jetted and balanced. Needles were raised, with larger main and pilot jets and from its steady growl at tick-over a touch of throttle sent the rev-counter needle reaching for the redline with incredible response, as the growl became more of a scream.

Kawasaki Z650 engine

Much of the metalwork and main casings were kept black. Selected ones were left as ally and polished. Output shaft casing was drilled and lightened to match the one-off chainguard. Anything unnecessary was removed to make it all as light as possible.

z650 cases

A Solid Kawasaki Z650 Fuel Tank

The Kawasaki Z650 tank was hand polished down to 2000 grit back to the steel. Then it got a one-off custom paint job reminiscent of the old BSA’s. The coloured panel was primed and given an under coat of British racing green. This was then over-sprayed with a coat of gunmetal grey metallic paint. The sides were simply lacquered.

fuel tank work

I replaced most of the original Kawasaki Z650 wiring. The headlight grill was also fitted, along with Hand hammered and polished alloy side panels. I then cleaned polished and rebuilt the original clocks. Wide flat tracker style bars with stainless/rubber grips were also fitted at the end. A custom flatter seat (multi layer variable density foam) and custom rear light under the original ducktail finished off the picture.

Kawasaki Z650 rearsets

Hand Made

Handmade rear-sets complemented the new more aggressive stance of the bike. This gave a comfortable riding position equally suited to scratching at the weekend and tearing it up around town. Even longer journeys were surprisingly easy. Wherever I went there were always complements and questions about the bike and the build.

Kawasaki Z650

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Any questions just email me at [email protected]

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