Yellow Hornet: Yamaha RZ350 Hybrid / Restomod

Yamaha RZ350 Hybrid Restomod

For Sale: 1983 Hybrid RZ350…

The Yamaha RZ350 was one of the last, most advanced two-stroke street bikes of all time, incorporating decades of two-stroke research and development. Known as the RD350 YPVS in the UK, the RZ350 boasted a liquid-cooled, rubber-mounted parallel twin engine with Yamaha’s Power Valve System (YPVS), a variable-height exhaust port that broadened the powerband.

“Producing around 50 horsepower from its 350cc twin cylinder engine and weighing 330 pounds dry, there were few experiences to equal the thrill of riding one of these small shrieking two-strokes…” —Ultimate Motorcycling

Yamaha RZ350 Hybrid Restomod

Unfortunately, the RZ350 was the beginning of the end for the road-going two-stroke sport bike. For that reason, RZ / YPVS builds are all the more sweet — especially so-called “hybrids” or restomods, which utilize modern suspension, brakes, and more, showing what could have been if the two-stroke street bike had continued to evolve.

Yamaha RZ350 Hybrid Restomod

This one comes to us from Martin Holgye, who started riding a Honda SL70 on the farm as a boy, worked as a motorcycle instructor at Sandown and Phillip Island Circuits, and retired from motocross racing at 46. He’s owned and ridden a wealth of different street and off-road bikes, including a Suzuki RG500 Gamma!

“I don’t believe that many RG500s would do as many kms each year as I do, which is about 6,000 a year. It’s a family heirloom and when I can no longer start it, it will go to my son.”

Yamaha RZ350 Hybrid Restomod

This RZ350 hybrid, known lovingly as the “Yellow Hornet,” came to him by way of the late Steve Street, Melbourne’s “Mr. RG500” — a man who helped Martin and many others sort out their RGs.

“The first time I met Steve Street he was riding the subject of this article. It is just such a pretty bike. I really lusted after it. When Steve found out that he was terminally ill, he gave me first option to purchase it. I have tweaked it in a couple of small areas and just ridden it.”

Yamaha RZ350 Hybrid Restomod

The wheels, brakes, forks, and banana swingarm come courtesy of a Suzuki RGV250, with Wilbers fork internals and a fully-adjustable Nitron rear shock absorber set up by by Australia’s Suspensions R Us. The engine is largely stock apart from a set of custom GP-style Jim Lomas pipes and VForce4 reeds, but it’s been completely rebuilt from top to bottom with NOS parts. Other highlights include carbor fiber mudguards, chain guard, and headlight surround; fully-adjustable Tarozzi rear sets, custom alloy radiator, Motogadget electronics, Metzeler Sportec M9 RR tires, and more.

Yamaha RZ350 Hybrid Restomod

Martin says the power delivery reminds him of a low-pressure turbo kicking in, making it a very nice bike to ride:

“It is a sweet handling unit, light and agile but with a longer wheelbase it has great stability over rough patches of road. The brakes off the RGV work a treat; super strong.”

Yamaha RZ350 Hybrid Restomod

Below, we talk to Martin for the full story on the “Yellow Hornet.”

Note: The Yellow Hornet is for sale here: https://www.bikesales.com.au

Yamaha RZ350 Hybrid: Owner Interview

Yamaha RZ350 Hybrid Restomod

• Please tell us a bit about yourself, your history with motorcycles, and your workshop.

An older brother taught me the basics of riding, and from there I soon was riding a Honda SL70 around the farm. A series of RM motocrossers followed that. RM80, 100, and 250. After that, enduro with a PE400. The road riding bug hit and the first road bike was a GPZ750R, followed by a 1992 GSX-R1100. After that was a GSX-R750T SRAD. It was this bike that I used when I was a part-time motorcycle instructor. I taught from learner riders, licencing, to advanced at Sandown and Phillip Island Circuits. I then purchased a 1999 YZF-R1 and rode the wheels off that thing.

After that I again got back into dirt bike riding as my son was dirt riding as well. His steed was a CRF50, mine was a 2004 Gas Gas 300EC. He started racing and so did I. He was racing KXs, so I got a 2010 KX450F. At the same time my road bike was an FZ1. I retired from racing MX at 46 years old. The eye-hand coordination was not what it used to be. Getting old’s not nice but better than the alternative!

Yamaha RZ350 Hybrid Restomod

After the FZ1 I purchased a Ducati Monster 1200S and that has been the best bike I own. About 6 years ago I purchased a RG500 Gamma, which I still have. Though that I met Steve Street, Melbourne’s Mr. RG500. He helped me and many others sort out our RGs. In fact, I don’t believe that many RG500s would do as many kms each year as I do, which is about 6,000 a year. It’s a family heirloom and when I can no longer start it, it will go to my son. The first time I met Steve Street he was riding the subject of this article. It is just such a pretty bike. I really lusted after it. When Steve found out that he was terminally ill, he gave me first option to purchase it. I have tweaked it in a couple of small areas and just ridden it.

My workshop is sufficient to maintain the RZ, the RG, and my trail bike.

Yamaha RZ350 Hybrid Restomod

• Why was this bike built?

In principal, the bike was built to replicate what a lot of English riders from the early 1980s where lusting after but could never afford. Mike Gibson in Perth, Australia is a UK expat and this was his build. He started with an RZ250. It wasn’t quite finished when he needed to fund the acquisition of an RG500, so he sold the Yellow Hornet to Steve Street. Steve changed and added quite a few things to the Hornet and then it came into my hands. The vast amount of the work had been completed already.

Yamaha RZ350 Hybrid Restomod

• What custom work was done to the bike?

The odometer shows 3,048 kms and this is the distance that the bike has travelled since it was built, including a full top and bottom end engine rebuild with many NOS parts including genuine Yamaha new crank, .5 oversized pistons, ceramic coated cases, all new genuine Yamaha bearings and seals (NOT YAMBITS), and custom made GP-style Jim Lomas pipes that are Euro 4 compliant. Which means it has a very nice note whilst not being too loud.

Yamaha RZ350 Hybrid Restomod

The induction system is completely stock including the airbox with the exception of VForce4 reed valves. It runs a stock 2T oil tank and pump. There are clear covers on both sides of the engine. In fact, apart from the VForce reeds and the JL pipes, the engine is stock. It goes quite nicely and starts, runs, and idles as it should.

Yamaha RZ350 Hybrid Restomod

It has a custom alloy radiator and runs a standard water pump impeller. Prior to painting, the tank was cut open and professionally re-welded and pressure tested and cap relocated. The cap is a quick release unit. The tank is in excellent condition and shows no signs of rust.

Yamaha RZ350 Hybrid Restomod

The instruments are Motogadget and were installed at the same time that the bike was professionally rewired. The indicators are LED.

Yamaha RZ350 Hybrid Restomod

The wheels, brakes, forks and banana swingarm are off a Suzuki RGV250. The forks run Wilbers internals and this work was completed by Suspensions R Us. The shock is a top of the range fully adjustable Nitron. HEL braided brake lines are installed and the front brake runs a Rizoma brake fluid reservoir.

Yamaha RZ350 Hybrid Restomod

The tyres are Metzeler Sportec M9 RR and have less than 1,000 kilometres on them. The Tarozzi rear sets are fully adjustable. I have adjusted them to suit me but may need adjusting for other people.

Yamaha RZ350 Hybrid Restomod

I think the carbon fibre front guard, rear hugger, chain guard, and headlight surround could be matched with a carbon fibre tank guard but I have settled with the current clear tank guard. I guess personal preference is your choice if you buy this bike.

Yamaha RZ350 Hybrid Restomod

It is a nice bike to ride and certainly gains plenty of attention every time I ride it. It handles well, the suspension works well on the road (I have not ridden it on the track) and the engine has those fantastic two-stroke characteristics that we love.

It is fully engineered and road legal as a modified vehicle. Vicroads has advised that the motorcycle is registrable as a modified vehicle in any state of Australia. The engineers certificate is attached to this vehicle. It is currently on full registration in Victoria and a RWC will be supplied if sold to a Victorian resident.

This is a well built bike and fully road legal with the engineering certification that is quite difficult to obtain these days.

• Does the bike have a nickname?

“Yellow Hornet.”

Yamaha RZ350 Hybrid Restomod

• Can you tell us what it’s like to ride?

It’s a very nice ride. The engine behaves as it should. It’s not a wild arm stretching thing when it hits the powerband. In fact it feels just like a low pressure turbo when it kicks in. Suspensions R Us re-valved the forks and set up the Nitron shock. It is a sweet handling unit, light and agile but with a longer wheelbase it has great stability over rough patches of road. The brakes off the RGV work a treat; super strong.

Yamaha RZ350 Hybrid Restomod

• Was there anything done during this build that you are particularly proud of?

The bike actually works. The suspension works, the electrics work, and the motor is well strong enough. And it pulls a lot of looks to.

The Yellow Hornet is currently for sale here: https://www.bikesales.com.au

 

 

2 Comments

  1. The RZ350 are grate bikes evolved from the RD TZ blood line suzuki parts on the yammy?nice paint job thanks for your build.

  2. Wow!! What a beautiful machine. I’ve always loved the look and sound of the RZ 350. Had one some 40 years ago, when I was a young lad. Should have kept it. You done a fantastic job, as did previous owner. Thanks for the look. Would love to buy, but 12000 miles to North America not in the cards.

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