I received an email from Hector Alberto who is from Australia and is a reader of this blog. He sent links to some YouTube videos of the tadpole trike and quad he has built. I am sharing them here for the world to see.
trike & quad ride on trails:
quad ride to park:
I wrote back to Hector asking him if he would send some pictures and share anything about his homemade trike and quad he cared to. Here is his reply:
The trike frame Is made of aluminium and lots of bolts.
For the steering system I’ve used the cheap 17mm ATV stub axle found on eBay and its respective end rod bolts (I was trying to understand how steering works in real).
I want to mention that with those pieces it was easy to make adjustments about angles related with the Ackerman law.
I used 20” BMX front plastic wheels. The original axle and bearings have been replaced by high rpm bearings to fit on the ATV stub axle.
The handlebars were attached using a 90 degree metal bracket between the stub axle and the handlebars. In general the trike use to work fine, but eventually the brake system mounted on the aluminium frame just fell apart.
Front sprocket 42t, freewheel 3 speeds
This picture shows the quad frame standing up when I was painting it.
I decided to go with a quad in order to help my wife bring our son along with her. The Quad measurements are 185cm long X 85cm wide. Yes, it is really a compact size when one takes into consideration that there are two people travelling on it. It has a COASTER BRAKE in the left rear wheel and the right rear wheel has an electric hub motor and a 160mm disc brake system. The quad is single speed. It has no front wheel brakes.
The trike conversion kits are so expensive in Australia, so I’ve been hunting for a used one. I got one old tricycle for Au$40. It came with one wheel traction (left one). Once I cut off the back part of the tricycle I went to a friend who welded it as I required. It includes a bottom bracket shell (found it as well on eBay).
The quad frame is using the same steering system as the trike.
The electric hub motor wheel is a 250w 36v “front wheel” for bicycles. It is mounted in the rear right side of the quad. This configuration allows the use either of the rear wheel power drives individually. When the rear wheel with pedal power loses traction you can put extra power in the electric hub motor wheel just by using the manual throttle as needed.
The average travel speed 15-20km/hr. Max speed tested with 98kg aprox., 27km/hr. Realistically, this is not a fast machine but it works excellent for the purpose; plus, my wife and my son love it.
I hope this help others to improve their designs.
As you can see in the link below they call it a 3 wheel BIKE car but that is ridiculous as it is obviously a TRIKE and not a bike. I don’t know why people do that … I mean “bi” means two and “tri” means 3. Can’t they count? 🙂
For those who want to build a tadpole trike it is imperative that they understand the science of the steering and ensure that they “get it right”. The “center point steering”, camber and caster settings, “Ackerman steering principle” and “toe in setting” all must be correct. Otherwise there will be “trouble in River City” and it could even lead to serious endangerment for the rider. At the very least handling will be greatly effected and tire wear will be a serious problem. When I first bought my Catrike Trail the dealer had the toe in off considerably and my brand new front tires wore out in only 30 miles of riding.
HERE is a webpage with a good explanation of toe in, toe out, camber and caster … what each is and what each does.
In the first video below this man says toe in should be 1/8 inch. That is too much for most trikes. 1/16 inch is preferable and is what is recommended by most trike manufacturers. Actually zero toe in maybe the ticket for some trikes including mine as with my weight on it I end up with about 1/16 inch toe in. There in lies another matter … it is best to set the toe in with the rider seated. This usually means a second person is needed as the mechanic to do the adjusting. It is not imperative that it is done this way, but it does work best. The more the rider weighs the more the toe in will change as the rider is seated on the trike. The closer you can get to zero toe in the better as long as the handling is ok. Never have toe out however as the handling will greatly suffer as a result.
Here are a couple of videos illustrating and explaining about these things.
As to actually measuring and setting the complex angles involved when I built my tadpole trike I simply used one of these (angle finder) …
As long as you use it properly and read it accurately it works fine for getting things right. My homemade trike rode and handled superbly so I must have got all the steering geometry correct.
The newer higher tech digital readout types would probably be better to use though …
I came across this video and thought it might be of interest to others. As a retired weldor/fabricator who has made my own tadpole trike it interests me. Here is a picture of the trike I made. (A friend was riding it when I took this picture so to protect his identity I have hidden his face.)
HOME BUILT RECUMBENT TRIKE, DETAILED PLANS AND CONSTRUCTION STEPS
HERE is a website about construction of a tadpole trike. It has several links to other resources.
HERE is a website about construction of an electric motor powered pedal assist tadpole trike. (lots of good information here about trike construction)
HERE is a video about how to make the direct steering handlebars.
And HERE is a listing of all the videos available by the man from the video above.