View Full Version : Sociable Tadpole Frame

04-13-2010, 08:09 PM
If making a frame like this...out of square tubing , what thickness / size?


but with this front end .....


24" in rear ... 20" (2) in front

with 2 pedaling folks

04-13-2010, 10:15 PM
Just need to get a single rear wheel on this ....


Radical Brad
04-14-2010, 11:37 AM
With a single wheel on the rear, that trike would roll on the first corner. It would be so unstable, that it may roll over just sitting there if a single person jumped in the seat! Get the riders sitting over the cross boom to place the center of gravity closer to the front wheels.


04-14-2010, 01:19 PM
the front end looks wider than you on the quad ?

what is different here ? .... battery weight


On your sociable tadpole attempt ... how wide and long did it need to be ?

04-14-2010, 03:32 PM
Envision if you will a triangle defined by the center of each tire contact patch. In the most basic terms, if the CG is outside that triangle you tip over.

With a single rear wheel the triangle is narrowest towards the rear. Thus if the CG is located towards the rear you have the least sideway movement before the CG is outside the triangle. Move the CG forward and you get into a much wider area of the triangle with a lot more stability.

This is why you see the rider sitting over the "axle" with legs hanging out front on tadpole trikes. And also why the AZ Delta Wolf delta trike places the rider back to the point of being in between the wheels.

Note that this is all about the CG, so if you have heavy batteries up forward on the picture you showed that would also move the CG forward.

Note that this discussion was simplified and does not account for lateral accelleration affects and tipping moments caused by the height of the CG.

04-14-2010, 07:44 PM
thanks ...

front trac is 58" wheel base is 70+-"

center of seat to center is seat is 24"

will it fit ?

right have to move seating forward

04-14-2010, 08:56 PM
BUT ... Batteries in front changes the center of gravity