Agent Orange: Honda CB750 Chopper

Honda CB750 Chopper

Honda CB750 “ChopRR” by JP Managa…  

In 1969, the Honda CB750 revolutionized the world of two wheels, earning its title as the “Original Superbike.” Before long, this sporting SOHC four-cylinder machine had become a darling of both the racing and custom scenes.

Honda CB750 Chopper

In California, a drag racer named Russ Collins began to gain national attention with his highly-modified Honda CB750-based drag bikes. In 1971, he built a 400-hp, supercharged, fuel-injected drag bike called the “Assassin,” which dominated its class.


Two years later, his triple-engine “Atchison” became the first motorcycle to break the seven-second barrier at the 1973 NHRA Supernationals.

“Collins was a bit of a radical in drag racing circles. First of all, he was going against the grain of the normal British or American-made drag bike of the time and was racing the new Japanese machines. And instead of wearing the standard all-black leathers, Collins showed up sporting colorful red, white and blue leathers.” –AMA Hall of Fame

“Atchinson” was destroyed in an accident that nearly killed Collins, but he managed to turn the setback into a stepping stone to greater NHRA heights.

“While recuperating, he dreamed up his next monster creation — The Sorcerer, featuring dual Honda 1,000cc engines. This bike ran a record-setting 7.30, 199.55-mph run that stood for 11 years.” –My Life at Speed

“The Sorcerer”

Terry Vance and Byron Hines of Vance & Hines both worked for Collins at RC Engineering before branching out on their own. Collins, who later turned to racing Top Fuel cars, was inducted into the AMA Motorcycle Hall of Fame in 1999, and passed away in 2014.

Enter our new friend JP Managa, who grew up in the Philippines and now lives in Portland, Oregon. He got his first bike about 10 years ago while living in New Jersey, and taking to two wheels was nothing short of a revelation for him.

“I’ve taken public transportation for most of my life and when I finally got a motorcycle it felt like my world shifted.”

The bike you see here is JP’s personal ride, a 1973 Honda CB750 that’s been through several iterations as his style, skills, and needs evolved. We love when someone takes inspiration from an  unexpected source, especially one as worthy as Russ Collins. Says JP:

“I looked at the race builds of Russ Collins and wanted to bring some of that essence on a hardtail chopper. I wanted the bike to feel classic, sound fast, and look tough.”

Honda CB750 Chopper

We’ve seen CB750 choppers in the past, but JP’s build strikes us as unique. Russ Collins’s creations put their mechanical workings on full display, their giant engines barely contained in steel skeletons and streamlined bodywork. JP’s chopper manages to capture that same racy, function-first attitude with a custom single downtube frame, narrowed and streamlined OEM tank, open-belt magneto drive, vintage 4:1 headers with a Kerker tailpipe, and much more.

Honda CB750 Chopper

JP thanks not only his partner, Emily, for supporting his “sick addiction” to motorcycles, but also the friends who helped him with various aspects of the build: Riegel Punla (@ClienteleCoatings) for the powder coating, Nathan Sykes (@nathantsykes) for the paint, and Alan Stedman (@cave.mfg) for the seat.

Honda CB750 Chopper

JP nicknamed the bike “Agent Orange” after the popular song by Filipino metal band SlapShock — a popular turn-of-the-21st-century anthem that referenced the infamous defoliation agent used in Vietnam.

Honda CB750 Chopper

JP says it’s a special feeling to ride something he transformed from a mere vision in his head into a physical reality, and the raw mechanical sensations of riding a four-cylinder chopper only add to the experience:

“There’s really nothing like riding a rigid chopper, makes you feel alive.”

Below, we talk to JP for more details on this 750 Honda chopper.

Honda CB750 “ChopRR”: Builder Interview

Honda CB750 Chopper

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

My name is JP, I was born and raised in the Philippines and currently live in Portland, OR. The very first memory I have with motorcycles was when I was living in the Philippines and my Tito Sam put me on the back of a bike and took me around the block. I don’t remember what kind of bike it was — probably a Yamaha or a Honda — I just remember it feeling really fast.

Honda CB750 Chopper

I got my first bike about a decade ago when I was living in New Jersey. I’ve taken public transportation for most of my life and when I finally got a motorcycle it felt like my world shifted.

Honda CB750 Chopper

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

This chopper build started off as a 1973 Honda CB750k.

Honda CB750 Chopper

• Why was this bike built?

This is my personal bike. When I moved to Oregon, I sold my first bike to get something slightly bigger to accommodate the open roads. The bike has gone through 4 to 5 different iterations since then. After a few years of owning the bike and learning more about the platform, I was able to piece together the ideal setup that I thought would be my version of a Honda chopper.

Honda CB750 Chopper

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

My concept for this build to create a Honda Performance Chopper. I looked at the race builds of Russ Collins and wanted to bring some of that essence on a hardtail chopper. I wanted the bike to feel classic, sound fast, and look tough.

Honda CB750 Chopper

• What custom work was done to the bike?

I started rebuilding this bike during the pandemic. Every part of this bike has been customized to a degree. Custom single downtube frame (4″ up, 0″ out, with a 2” stretch on the rear).

CB750 Chopper

Custom open belt magneto drive (inspired by ARD), custom-laced 21” front & 18” rear wrapped in Firestones, OEM Honda tank that was narrowed and shallowed to fit the proportions and lines, vintage 4 into 1 headers with a Z1 Kerker muffler, and the list goes on!

• Does the bike have a nickname?

I named this bike “Agent Orange.” The inspiration comes from a song by the band SlapShock — a Filipino band from the 2000’s. I was still in the Philippines when they started getting big and one of my favorite songs was Agent Orange (RIP Jamir).

Honda CB750 Chopper

My good friend Riegel Punla of Clientele Coatings (@ClienteleCoatings) did all of the powder coating on this bike and Nathan Sykes (@nathantsykes) of Sykes Customs painted the tins. The seat was custom made by my dear friend Alan Stedman (@cave.mfg).

Honda CB750 Chopper

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

It’s a stock 750cc engine. I think it’s slow to today’s standards, but it’s fun and exhilarating to ride. There’s really nothing like riding a rigid chopper, makes you feel alive.

CB750 Chopper

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

Riding something you built from your mind to the physical world is a special feeling. The bike feels nimble, the engine sounds great, and the view from the cockpit is otherworldly. It’s rigid with a nice riding position, the stance sits higher than where it originally was, and the fresh top end on a 50 year old engine is a nice bonus.

CB750 Chopper

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

I’m proud of being able to stay true to what I wanted without compromising. I’ve learned along the way that the cooler it is, the more headache it comes with to make it work.

Being able to figure out the custom magneto setup was an accomplishment that keeps on giving every time somebody asks me what the open belt is for.

Honda CB750 Chopper

• Is there anyone you’d like to thank?

Thanks to my partner Emily for supporting my sick addiction and obsession over motorcycles and my friends who’ve helped along the way!

More Photos

Follow the Builder

Personal IG: @JPManaga
Bike IG: @CB750_ChopRR
Powdercoating: @ClienteleCoatings
Seat: @cave.mfg
Paint: @nathantsykes


  1. steven livingston

    That one pic is in front of The Alibi, best tiki bar in Portland.

  2. I would like to know how did the painter achieve the “crazied” patina in the tins? Nice build by the way!

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