Pedal Power Farming

SUBHEAD: Two articles on the development of pedal power farm tractors by Farm Hack.
Second Prototype

By Staff on 15 November 2014 for No Tech Magazine -

Image above: Field test of second prototype of peddle powered farm tractor. From original article.

The Culticycle is a pedal powered tractor that can cultivate, seed, spray, or pull gear for most low horsepower tasks. We talked about the first prototype almost two years ago. A new version has now been released, built around a modular tractor frame. Tim Cooke explains us how it’s built and how it works: 
“The math behind the idea is nothing more than observing that a lot of the work a tractor does – shallow cultivation, seeding, flame weeding – requires very little of its available horsepower; and since these jobs are best done between 3 and 5 mph, a bike can be geared down low enough that a human can produce the necessary horsepower.

Take the cranks, seat, and handlebars from a bike and center them in a 4-wheel, lightweight, modular tractor frame: the obvious frame material is telestrut. For the front end use 20″ bike wheels and forks. You need about a foot of clearance but you want a low center of gravity and as much traction as possible: get 25 x 8 ATV tires for the rear, ideally with aluminum rims.”

“Assume you’ll pedal at 60 rpm and use a gear ratio of about 2.2 on the cranks to 3 on the differential. Now you have 25/12 x π for one revolution of the tire, x 22/30 gear ratio, x 60 rpm, x 60 minutes, divided by 5280 feet per mile = 3.3 mph. Pedal at 70 rpm and you’re at 3.8 mph. Meanwhile you’re not hunched and twisted and causing joint damage, you’re getting aerobic exercise.

And if your farm is bigger with tighter time constraints, have 2 or 3 of these machines set up specifically for those 2 or 3 row spacings that you use the most, and put the interns or volunteers on them. For instance one with a basket weeder, one with sweeps, one with finger weeders. Or fatten the front tires and throw a 12 foot aluminum ladder across the chassis and hang those big plastic harvest bins from each end, out over the beds, for lettuce harvesting: you could put 100 pounds on each end of the ladder.”

Video above: Field test of  second prototype of peddle powered farm tractor. From (

First Prototype

By Staff on 31 March 2015 for Greenhorns -

Video above: Field test of first prototype of peddle powered farm tractor. From (

“The Culticycle is a pedal powered tractor that can cultivate, seed, spray, or pull gear for most low horsepower tasks. Small tractors do many jobs very well and very fast, but also consume fuel, compact soil, cost a lot, and cause physical damage to the operator -– mainly spine and joint problems. Many of their jobs could be done, slower but better, by human pedal power.
This prototype consists of:
  • the front ends of 2 bikes welded together at 42” on center;
  • a lawn tractor differential mounted in a unistrut rectangle for a rear end , with 3/4″ round axles and 20” ATV tires;
  • a bike frame welded above the rear end with motorcycle sprocket and chain driving the differential (a springloaded idler tensions the chain);
  • a belly mount lift to hold cultivators, seeders, etc.;
  • a bike handlebar, separate from the bike frame and joined to the front end, steering the front wheels.
The materials are rebar, unistrut, landscape rake tines, and parts from bikes, an ATV, and a lawn tractor. It attempts to show that human pedal power can do some jobs of small tractors, albeit in twice the time, and that the design can be simple enough that no extra weight is needed for traction. The effort required is similar to climbing a 10 degree slope on a seventies Schwinn 3 speed. This prototype was built for testing: a more easily buildable version is in the works.”

Some Background

By Stall on 3 March 2015 for Green Horns -

An ace team of farmers, fabricators, engineers, and pedal-powered truckers gathered at Metro Pedal Power in Somerville, MA for a weekend build event. What project would bring such an intriguing group of individuals together? Only the culticycle, a pedal-powered cultivating tractor designed by Tim Cooke, that uses human brawn and bicycle brains to replace fossil fuel powered tractors for lightweight field cultivation. Culticycle video here!

First, a quick introduction of our weekend hosts. Metro Pedal Power is a pedal-powered hauling business in the Boston area, replacing box trucks with custom-built freight trikes to haul last-mile inter-city freight such as compost, recycling and CSA shares. They hope to reduce urban congestion and traffic, improve human wellbeing, and encourage others to see the appropriateness of pedal power in the urban environment.

Wenzday and Eric from MPP generously hosted the build event at their fully outfitted shop in Somerville, without which the event would have been wholly impossible and a lot less comfortable. Many thanks to them and the rest of their team for hosting, convening and offering their fabrication skills.

The goal of the pedal power hack was several fold. We wanted to showcase an already built culticycle for those who had never laid eyes on it before, and bring minds together to brainstorm improvements as Tim moves forward in his development of the tool.

Several attendees also were in the process of building their own culticycle, or had already done so, so we additionally hoped to build some replacement components and share knowledge of the build process that we could take home with us.

Additionally, we wanted to document the tool more thoroughly, specifically in CAD design format to be shared freely on the Farm Hack Tools platform. We also wanted to use this opportunity to shoot video and take photos to capture the Farm Hack collaborative design and build process as it was happening.

With those goals in mind, we set forth Saturday morning by working together to assemble a pre-built culticycle, so that everyone would have a chance to look over the design and get a sense of how the pieces fit together. We then split into several teams.

Team 1 started from scratch with steel stock, cutting and grinding the structural pieces of the chassis – using Tim’s documentation to guide their effort but also improving upon the design as they went.

Team 2 worked on “Culti 2,” a culticycle which was about halfway completed but still needed steering linkages and the parallel lift which raises and lowers the tools.

Team 3 began to rebuild the “belly mount,” or toolbar, which is attached underneath the culticycle and which the weed killing tools are clamped to. This new and improved belly mount will be delivered to Hawthorne Valley Farm and installed on their culticycle, replacing the older, less robust model which was a part of the earlier culticycle design iteration.

For a day and a half, the shop buzzed with activity as folks dropped in to observe the process or get their hands dirty cutting, grinding, and welding. Lu Yoder brought along his pedal powered grain grinder, grinding wheat and making bread on Saturday and grinding corn for his brother Chris’s CSA Sunday.

By midday Sunday, we had made significant progress on both the second and third culticycles, finished a pile of DIY, cheaply made star hoes, nearly completed the belly mount, and made many small modifications and improvements to the Culticycle.

Farm Hack supports an approach to tool design and innovation that is built on principles of resilience. Instead of the top-down approach to tool development put forward by corporate agribusiness, the event this weekend prioritized local manufacturing, easily repairable and modifiable tool design, and collaborative and iterative research and development. For the better part of the last decade, Tim Cook has spent countless hours in his basement shop designing, tinkering, and building this machine from scratch.

This is a familiar model: an isolated innovator who is the focused, driving force behind a revolutionary tool design. The community of support which showed up this weekend to pitch in, cut, weld, prototype, and offer their design feedback and support are a vital part of this process of resilient design.

As we concluded the weekend-long build sprint, the conversation turned to next steps for the Culticycle and for Farm Hack, both community-driven efforts to re–imagine the landscape of our collective farming future. Keep an eye out for upcoming opportunities to be involved with both, including another eastern Massachusetts culticycle build in the next weeks, a Farm Hack event at the Draft Animal Power Field Days in Cummington, MA this September, and a late Fall event at Lu Yoder’s place.

And if you’re inspired by this Massachusetts flurry of activity, keep in mind that Farm Hack is made up of the collective efforts and contributions of all of us. If you would like to organize an event in your community but you’re not quite sure how to do it, check out the helpful event organizing tool on the site.


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