The Monster: Supercharged 1969 Bonanza Minibike!

Supercharged Minibike

Wolf Creek Garage builds a blown mini tracker for The Wild One! 

In 1958, Michael O. Farrand founded a high-performance go-kart company, Custom Kart, in Central California. Operations soon moved to San Jose, and the company would go through a series of name changes as it grew: California Kart, Kart Industries, and finally Bonanza Industries.

Supercharged Minibike

Though Bonanza’s bread-and-butter were go-karts, in 1962, Farrand sought to build a minibike that would align with the company’s racing tradition:

“The objective was to create a racing bike that would be more effective in the corners, capable of much higher speeds and have the capacity to transport an adult up the steepest incline.”

Bonanza Minibike

The result was the Bonanza BC-1000 and its variants, which would sell more than 50,000 units over their production run.

Supercharged Minibike

At the recent One Moto Show in Portland, we came across one very trick 1969 Bonanza, built to race in The Wild One at Castle Rock — an annual race hosted by the same organizers as The One Moto. Nicknamed “The Monster,” this Ducati-themed Bonanza tracker is the work of a Don Neely, a heavy equipment mechanic who’s been riding minibikes and motorcycles for nearly 60 years and runs a custom fab shop on the side:

Wolf Creek Garage is currently a side business where I spend most of my time when I’m not riding or racing. I do modifications, maintenance, custom exhaust, fabrication, engine builds. Vintage bikes are my favorite, especially flat trackers; custom builds that are out of the norm are also fun.”

Supercharged Minibike

Don details the Monster’s custom work below, which is extensive: springer front end, four-disc clutch, billet and forged engine internals, custom ground cam, roots supercharger, reinforced engine cradle, and much more. Don says the ride will be thrilling, to say the least:

“Minibike handling has always been a bit sketchy, add more power then put it on a quarter mile clay oval they definitely have pucker factor, especially in the turns…. Probably around 90 lbs. and currently geared for 70 MPH.”

Supercharged Minibike

We’re sure the Farrand and the original Bonanza builders would approve, as would the original owner of this mini:

“It’s always satisfying to save a bike from being shredded and melted down. At one point they were the center of some kid’s world.”

Supercharged Minibike

Below, we talk to Don for the full story on the build. Show photos by Fouad “Moh” Mohiadeen (@astronaut_bear).

Supercharged Bonanza Minibike: Builder Interview

Supercharged Minibike

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

I’m a heavy equipment mechanic by trade, I enjoy mechanical work, welding and fabrication. I live in the Pacific Northwest so the rainy season gives me plenty of time to work on projects.

I started riding minibikes at age five, then onto motorcycles; they have been around my whole life, and I’m sixty four now. I own several late model and vintage motorcycles as well as several minibikes rescued from the scrap heap or off the internet.

Wolf Creek Garage is currently a side business where I spend most of my time when I’m not riding or racing. I do modifications, maintenance, custom exhaust, fabrication, engine builds. Vintage bikes are my favorite, especially flat trackers; custom builds that are out of the norm are also fun.

Supercharged Minibike

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

1969 Bonanza.

• Why was this bike built?

I typically build one minibike each winter to race in The Wild One at Castle Rock in the summer. I’ll race it a few times then retire it to the “bike room” for display and an occasional track day.

Supercharged Minibike

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

My last two minis were influenced by Kenny Roberts’s TZ750, “They don’t pay me enough to ride this thing.” It was built to race flat track on blue groove clay. Minibike handling has always been a bit sketchy, add more power then put it on a quarter mile clay oval they definitely have pucker factor, especially in the turns.

Supercharged Minibike

• What custom work was done to the bike?

Springer chromoly front end. Custom Bully four-disc clutch. Billet and forged engine internals. Custom ground cam. AMR300 roots supercharger, 50% underdrive. Aluminum reverse cone exhaust. Head ported, all new valve train and roller rockers. Adjustable blow-off valve. Modified 24mm flat side Mikuni. Radial brake master cylinder with dual piston master cylinder. Quick change gearing, currently set for 70 mph. Reinforced engine cradle and rear axle carrier. Various plumbing and brackets.

Supercharged Minibike

• Does the bike have a nickname?

The Monster.

Supercharged Minibike

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

Probably around 90 lbs. and currently geared for 70 MPH. Not sure on the HP.

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

Not yet, just finished it before The One Show and it’s been constant rain since. Looking forward to a decent day so I can break it in and likely do a little jetting. I suspect it’ll pull pretty hard, as it’ll build boost right off idle and should be about 12 PSI when clutch locks in at 3600 RPM. Rev limit is 8000 RPM.

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

It’s always satisfying to save a bike from being shredded and melted down. At one point they were the center of some kid’s world.

Builder Thanks

HNC Powder Coat
Bully Clutches

Follow the Builder: Wolf Creek Garage

3 Comments

  1. Elam Blacktree

    Bloody awesome!

  2. We had a Bonanza mini with a Hodaka 100cc engine. Learned how to ride anything.

  3. Bigshankhank

    That doesn’t look like the same engine as either of the two advertisements, is that a Predator/Honda OHV clone? Would love to know what the base engine is.

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