This build began in May 2014 and finished in June 2014. The idea for the build arose from the need of a tow-bike for the Pedicab Trailer that I built earlier that year.
Together the two (pedicab trailer and tadpole bike) created a very nice system which I took out to Burning Man that year in order to gift rides to the citizens of Black Rock City. The Gitche Gumee is also fun to ride by itself.
A BIG thanks to Atomic Zombie DIY bike projects for providing the plans for this project! Note: I utilized Atomic Zombie’s step-by-step “Hammerhead Winter Trike” plans for this build. These plans can be found in AZ’s “Bicycle Bonanza” book of plans and also online.
And a shout out to the Reno Bike Project for being an awesome source of super low-priced salvaged bike parts. You guys rock!
This Gitche Gumee Tadpole build was based off of plans for the HammerHead Winter Trike (shown below).
Detailed step-by-step instructions to build this trike can be found at Atomic Zombie.
The main frame and drive train of this build came from a 1998 Gary Fisher Gitche Gumee mountain bike. 26-inch; rigid suspension; 21-speed.
Collecting parts. Two matching forks found at the Reno Bike Project. One read Huffy, one read Roadmaster, however they were equal in size, and length — a critical requirement for the front end of this trike’s design.
Salvaging and prepping one of the needed head tubes tube cut from a donor frame. The head tube is then ground clean and sanded smooth.
Two matching head tubes ground clean, sanded smooth, and ready to weld.
Laying out the parts of the front end in order to visualize things. This is done prior to any welding. The cross members are cut from 1″ EMT electrical conduit.
Using a template to mark the “fish mouth” cuts on the ends of the EMT crossmembers. Fishmouth cuts are used when welding round pipe together at right angles.
Tack welding the cross members to the head tubes. Proper alignment is critical here.
Welding each (left and right) head tube to the center head tube. Note: the center (orange) forks are in its tube simply for alignment purposes. The center (orange) forks will be removed after the welding of the left and right forks. Note the use of a rod to align all the forks.
After the left and right head tubes were welded to the center head tube, I removed the center fork, and temporarily installed the front wheels to get a visual. The tadpole is taking shape!
While I had the front wheels installed, but not yet the steering linkage connected, I took a picture of the wheels in a position in which they will never ever be (hopefully) after the tadpole is complete.
The center fork’s left and right fork sides are cut from the fork’s crown; leaving only the steering tube and crown. Tip: Save the side pieces for later use. The crown is then ground clean and smooth.
The tie rods for the steering linkage are pictured below. Sourcing an economical pair of these proved more challenging than I had anticipated. Ultimately I found these online through Northern Tool and Equipment [Item #13811 – Plated Steel 13″ Tie Rod Kit].
[Since building the Gitche Gumee Tadpole i’ve learned that Northern Tool no longer carries this part. However I see that they do carry individual tie rod end bearings; so one could make her own tie rods. – Ed.]
Pieces of flat iron (salvaged and cut from used bed frames) used to connect the tie rods to the forks and steering tube.
Center steering tube with the tie rod connector plate welded to it.
Tie rods bolted onto the the center steering tube’s mounting plate.
Use a straight rod to align the forks. Place the forks in a straight-ahead position.
Using a piece of string to determine the angle of each fork’s tie rod connector plate in order to achieve an “Ackerman” steering geometry to the steering linkages.
What is Ackerman steering geometry and why is it important? Click here.
With the steering linkage installed, it was simply a matter of installing the front wheels in order to perform a quick rolling test ride. 🙂
In order to strengthen the front end, trusses were added connecting the top tube to each head tube. I repurposed the original fork sides from the Gitche Gumee’s fork for the tadpole’s trusses. [I thought it only fitting.]
No bike build project is complete without painting. Here’s the front end painted to match the pedicab trailer that it will be towing.
The complete Gitche Gumee Tadpole. The intended use of this machine is as a tow bike for the pedicab trailer that I built the previous month.
Incidentally “Gitche Gumee” is the Native American name for Lake Superior — meaning “big water”. #TheMoreYouKnow