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View Full Version : Musing on a tadpole velomobile



stormbird
07-28-2013, 02:20 PM
I am currently considering building a velomobile , spurred on by the fact a friend is picking up a Mango in August and there is no way my tired Kettwiesel will keep up with that baby !


This is one of 2 [ the other deals with a delta planform ] threads where want to push out some design ideas and hopefully get some useful ideas from you the Zombie community.


First my personnel definition of a velomobile is :-


All wheels sprung
Headout body with provision for roof when raining
Luggage space for shopping and , hopefully enough for solo camping taking some food , so as not to have to tow a trailer.


Why not a tadpole


Well full suspension is very complicated on the front wheels of a tadpole especially if you have little access to machining , let's face it that is NOT the Zombie way !


The only home made option I have seen is moving kingpin , these has some problems with a lack of travel and bump steer , both it seems you have to live with.


At the rear I will make a very light rear triangle [ like the old 10 speed racers ] pivoted on bearings and with an elastomer for suspension or maybe bungee cord wrapped a few times around some mountings ?


At the front the pedals will be fastened to short cranks and the chain will go down directly to a Sturmey Archer 3 speed hub mounted where you would normally have a couple of idlers this mid drive will remove the need for a front mech and enable changing when stopped.


The mid drive should help get the chain low enough to pass under the seat without further idlers.

First I will build a mule , basically just the trike part and when that is satisfactory I will look at ways of either building a shell for it , or building a monocoque materials will be wood & fabric probably.


oh did I say it needed to be light < 75lb and cheap !


regards Paul