Building a tadpole from scratch...

todayican2

100 W
Joined
Apr 22, 2009
Messages
139
Anyone done this before? I saw these wheels online. apperently they are for a "granny style" upright trike (2 in the rear)
would these make good front wheels for a tadpole?

http://www.bikepartsusa.com/bikeparts/item/01-6778806/search/Miami-Sun-Sun,-24x1.75,-Rear,-Trike,-Chrome,-Steel,-Wheel&category=search
 
There is a REALLY NICE tadpole with air ride suspension at the Autospeed e-mag. I don't have a direct link but it is easy enough to find, looking for the "Air Trike". The design has gone thru a few versions, and I intend to build one once I can get the suspension parts (firestone/bridgestone 4001), or build something similar (I've got four go-kart tires and some aluminum plates and some valves, but they'd be huge, like truck-sized).

Mine will be a little longer, closer to 8 or 9 feet (cargo space/etc), and semi-recumbent instead of fully-recumbent, but based on his suspension system and front steering rack/etc.

Nice thing about his articles is they explain *why* he chose components or made design decisions, which helps a lot in figuring out what things I would want out of such a design, and how they would help my particular application.


As for the wheels, I have some stub-axle 20" wheels from a pretty nice baby stroller that was designed around and built from bicycle parts. They'll be my front wheels.
http://electricle.blogspot.com/2009/05/new-trailer-from-baby-stroller.html
 
A hearty "Yes" to the Julian Edgar series on trikes in Autospeed. He really does the engineering right before your eyes! Absolute must read for tadpole owners/builders.
otherDoc
 
My only complaint about the articles is that he does not give actual measurements to be able to easily duplicate the work. He does say that anyone can contact him and get them, but I've never gotten a response to any attempts to contact him.... Since my planned build will be different in shape/size, the exact measurements would not be applicable in several places, but having them as a basis to build the prototype model from (probably in Lightwave) so I could then modify it and get the new numbers from, would be a significant help. :)
 
"FreddyFlatfoot" (a.k.a. Rob) built a trike and shared some bits:

http://endless-sphere.com/forums/viewtopic.php?f=6&t=2523
 
Has anyone built one from plans on this site?

http://www.atomiczombie.com/product-warrior.htm

Looks like a cool resource :)
 
This is one I built a few years ago for my sons.


The seat slides along the bottom tubes and is supported at the rear by seatposts that slide into the upper chainstays. It was very popular with the neighbours' kids, but not so popular with their mothers as there was no chain guard...

The front wheels are BMX with 14mm solid axles.
The steering housings are cut-down loose bearing headsets.
The steering arms are old alloy stems.
Tubing is all CroMo, partly recycled and partly bought for the purpose.
The seat is a remodelled folding picnic chair.
There are no front brakes – my sons found the quickest way to stop was to pull hard on the rear brake and do a sharp 180 degree turn while leaning in the appropriate direction. Knobbly rear tyre quickly became a slick.

I can get some more photos of the various bits if you want, as the trike is currently dismantled in the garage.
 
Gathering parts now for a cross between the warrior

http://www.atomiczombie.com/product-warrior.htm

and the streetfox

http://www.atomiczombie.com/product-streetfox.htm

Going to run a 26" rearhub from E-Bikekit.com

Brad does a nice job with the plans, and builds with basic tools.
 

Attachments

  • trikeparts.jpg
    trikeparts.jpg
    49.9 KB · Views: 2,102
Basicly the warrior design with rear suspension. I'd like to maybe come up with a joy stick type steering too.
 
So ... a street fox with disc brakes ?

Use Brad's rear sus. or other ?



nineball said:
Basicly the warrior design with rear suspension. I'd like to maybe come up with a joy stick type steering too.
 
So ... a street fox with disc brakes ?

Use Brad's rear sus. or other ?

Yea...you could use the rear fork design of the warrior, and just add a shock.

I plan on towing a trailer, so I'll lower the fork and extend it past the dropouts for a hitch. Plus a little longer wheel base, to accommodate the power supply :wink: , and maybe a tad wider for control at speed.
 
What is the best method for attaching the front wheels? 14mm threaded axle or 20mm bolt on style would be the choice for me, but I haven't wrapped my head around how to hold the axle best. Just a through hole in the steer tube to clamp through? Or maybe a fancier setup?


I am needing a bent, and want to give a shake at a tadpole.
 
I just downloaded the plans for the Warrior trike. 178 page pdf with lots of pictures. I seem to agree with most of the design but there is something about that rear fork design that just doesn't look right. I plan to build mine off the plans but then gusset the rear and and other areas of the frame to make it stronger. There Handle bar choice look a little low and short but will see in practise.

One thing I was thinking about is the front brakes one lever two brakes.Hydraulic sounds nice have to come up with a little manifold adaptor for my hydraulics so they both work from the one lever. I wont bother with the rear brake. I plan to run my 5304 26" rim on the back and mount a 20ah 36v headway pack under the seat. I only want a 7 speed on the back and no de railer on the front just a large chain ring at the front
Kurt

3927342051_99f9b888a4.jpg

3927341781_143956eb65.jpg
 
The one I am going to build, the Atomic Zombie Warrior ( http://www.atomiczombie.com/product-warrior.htm ) uses a 20mm bolt thrugh hub like this: http://www.bikepartsusa.com/cgi-bin/category.cgi?item=01-115516&source=froogle

John, Im going to build a couple, I could build you one if you like, we could do some horse tradin for some drive stuff :)
 
Although the offer is tempting, I would rather build it myself. I have 14 bikes plus parts here to use, and a few welders that need some exercise. A few particulars are just needing more thought on my part.
 
What is the best method for attaching the front wheels?

You can use the bolt and tab design, like Brads plans,or you can just weld the bolt right to the steering tube. @ 15 deg.
 
One thing I was thinking about is the front brakes one lever two brakes.Hydraulic sounds nice have to come up with a little manifold adaptor for my hydraulics so they both work from the one lever. I wont bother with the rear brake. I plan to run my 5304 26" rim on the back and mount a 20ah 36v headway pack under the seat. I only want a 7 speed on the back and no de railer on the front just a large chain ring at the front
Kurt


I used the single brake lever for both front discs on my rebuilt Tricruiser but I am now finding that differential braking with the two levers is really fun and allows better cornering. It's like the dual rear wheel brakes on the old dunebuggies and autocross cars. Really fun!
otherDoc
 
johnrobholmes said:
What is the best method for attaching the front wheels? 14mm threaded axle or 20mm bolt on style would be the choice for me, but I haven't wrapped my head around how to hold the axle best. Just a through hole in the steer tube to clamp through?

I drilled a hole through the steerer tube then welded in a short length of tube with an ID of 14mm. I was a bit concerned that there would be insufficient support for the axle, but it's held up well. The bottom end of the steerer tube where I drilled through has a wall thickness of about 3mm.
P1010912.jpgP1010913.jpg
 
Back
Top