Handbuilt Star: Aluminum-Clad Yamaha TX750

As Seen at Handbuilt: Ronnie George’s Yamaha 750 Stunner… 

Only available for a short time in the 1970s, the Yamaha TX750 remains a relatively rare and obscure model. At the time, Yamaha already had the XS650 parallel-twin, and most of the other manufacturers were putting their R&D efforts into inline-fours. Why would Yamaha opt to develop a completely new 750-class parallel-twin superbike instead of simply punching out the XS650? One simple reason: vibration.

Yamaha wanted to build a big-bore parallel-twin as smooth as a four. To do so, they used an “Omni-Phase” balancer consisting of two counter-rotating weights driven by a single chain from the crankshaft. Moto journalists loved the engine:

“The result is smoothness beyond belief. Shut your eyes and you are on a four. It couldn’t be a twin.” –Cycle World, 1974

The bike handled well, too — at least for the time. Unfortunately, the early engines had reliability issues. Yamaha worked out all the bugs for the 1974 TX750A, which included 18 engineering updates. However, sales never recovered, and the model was soon dropped from the lineup.

At the Handbuilt Show last month, our very favorite build might have been this custom 1974 TX750A from our old friend Ronnie George, an Indiana steelworker who builds bikes in his home garage. We featured Ronnie’s CB350 way back in 2018. We didn’t even know he was working on a new build until this stunner turned up at the show.

Ronnie originally intended to build a street tracker until he came across a photo of Kenny Roberts’s YZR500 Grand Prix bike. Quickly his vision shifted, and he decided to tackle something he’d never done: shaping his own custom aluminum bodywork.

“I built this bike to challenge myself. I wanted to progress my skills and see if I could actually do the things I was dreaming up in my head…and that I’ve seen some other builders take on.”

Before the bodywork, however, Ronnie modified the frame extensively, converting it to a monoshock setup that’s fully adjustable for ride height and shock angle. The R6 rear shock is matched with rebuilt forks and a dual disc front brake conversion accomplished with modern R6 goodies and various adapters Ronnie fabbed up himself.

He fabricated a new oil tank and added an oil cooler — all with stainless hard lines and AN fittings. Meanwhile, Ronnie’s custom-built 2-into-2 stainless exhaust and handmade mufflers tricked us into thinking there was a two-stroke engine behind the fairings — perfect for a bike inspired by King Kenny’s YZR!

Then there’s all the custom bodywork shaped from 3003 aluminum sheet — incredible that this is Ronnie’s first foray into this type of metal-shaping!  The Yamaha speed-block livery is painted directly on the highly polished aluminum, and the Dane Utech (@plzbeseated) did up the custom seat.

All in all, this is one incredible build from a full-time steelworker who’d never shaped aluminum before…and just the kind of hand-formed creation that makes the Handbuilt Show so special. Below is our full uncut interview with Ronnie about the build, along with more photos courtesy of Craig Stuart (@scrambler_ams / show shots) and Ronnie’s wife, Kristen (@sweetblissjunkie / outdoor shots). Enjoy!

TX750 Custom: Builder Interview

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

My name is Ronnie George. I’m a 42-year-old steel worker from Northwest Indiana. I’m married and have a 24-year-old son. I’ve been around motorcycles for most of my life but I really got into them around 2012. I built my first bike, a 1981 Kawasaki KZ440 and ever since I just can’t get enough! I do pretty much everything on my builds in my two-car garage. From metal fabrication, to powdercoating.

• What’s the make, model, and year of the donor bike?

The bike is a 1974 Yamaha TX750A. It’s a quite obscure model, for many reasons.

• Why was this bike built?

I built this bike to challenge myself. I wanted to progress my skills and see if I could actually do the things I was dreaming up in my head…and that I’ve seen some other builders take on.

• What was the design concept and what influenced the build?

The original concept for this build was a totally different direction. I had originally wanted to make a flat tracker. I was searching for inspiration and came across a Kenny Roberts YZR500 photo and then everything changed!

 

• What custom work was done to the bike?

I modified the frame very heavily…it’s converted to a monoshock rear, inspired by Yamaha motocross and race bikes of the time frame…using a more modern R6 shock. It’s fully adjustable for ride height and shock angle.

I fabricated a new oil tank and moved it to the rear, added an oil cooler and made all custom lines (including stainless hard lines and AN stuff).

I fabricated a 2-2 stainless exhaust the takes an interesting route through the frame, and it exits through handmade two-stroke style mufflers.

The front forks were rebuilt and the front brakes converted to dual disc, using more modern R6 components…hanging on a bunch of handmade adapters to make it all work.

The rear brake is still a drum but I converted it to be hydraulically actuated…using a slave cylinder from a Honda Civic.

The wheels were re-laced and polished, then wrapped in new Metzeler Sportek Klassiks.

Handmade rearset foot controls were done from scratch. I then shaped and formed all of the aluminum bodywork from a flat sheet of 3003 aluminum…including a cockpit style gauge pod. The Yamaha livery is painted on the aluminum.

The beautiful seat was made by Dane Utech, @plzbeseated — he knocked it out of the park! Nearly everything was then polished. There are numerous small things all over the bike that I made by hand but I can’t seem to remember everything!

• Does the bike have a nickname?

My wife nicknamed it “Space Oddity”…although I just call it the TX.

• Any idea of horsepower, weight, and/or performance numbers?

As for power…not much is done to increase it. I’d assume it’s probably near the factory number, which was about 74 HP. I’ve never weighed it but I am curious as to what it has ended up to be.

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

I’m definitely proud of the entire project but shaping all the bodywork and actually having it come out to look like I had imagined was the most satisfying. It was my first time shaping aluminum…so it was a difficult endeavor for me.

• Is there anyone you’d like to thank?

I’d like to thank my wife, Kristen, and son, Bryce, for the support and encouragement during the long project. Dane Utech for the amazing seat. Mike Muller from Federal Moto for assisting me in powdercoating the frame at his shop, he’s a great fella. And Jaron Kaczmark for vapor honing the carburetors. I’d also like to give a huge thank you to Bear and everyone at Old Bike Barn for their support. This build was part of the Greasy Dozen Builder Collective and they helped immensely with sponsorships!

Photo Credits

All of the amazing photos from this year’s Handbuilt Motorcycle Show were done by Craig: @scrambler_ams. The fantastic outdoor shots were done by my wife, Kristen: @sweetblissjunkie.