Aerodynamic TWIZY how to improve

Hi everyone!!!
As may be I’ve dreamed or I posted it somewhere but I’ve a question:
Since the Twizy has a disgusting CX coefficient can anybody list a TO DO list to improve it.
I guess perfectly sealed doors to start.
Then? Rim cups? Like the Audi A2?

To make the Twizy more aerodynamic which only really affects it over 30mph or so, is windows and doors. Besides these two key items that stops the air to plunge into the back seat there isn’t much else you can do. The Twizy is not meant to go at high speeds to start with so CX is not a huge factor. Weight and rolling resistance being a bigger priority. Endurance with the battery is a challenge given its short range, and because of this higher speeds that uses up more energy per km/mile is not encouraged. In contrast the Zoe is more relevant to have aerodynamics and it does with a top speed of 84mph, compared to the 52mph of the Twizy. The PowerBox has given me more speed, having reached 72mph in the Twizy. The wind noise is pretty bad at that speed lol :smile:

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72mph? are you kidding me? probably was downhill right? with doors and windows?
rolling resistance you mean frictions created by the gearbox and ball bearings on the wheels right?
Endurance with the battery is a challenge given its short range, and because of this higher speeds(speeds of what?..gearings? that uses up more energy per km/mile is not encouraged.

If it’s a problem of gearing can’t we simply make gearings with a bit bigger ratio to reduce rpm and improve top speed?

…man if 72mph its just with power box that’s awesome! but I’he heard there’s another open source stuff that makes even more complicated stuff that the box made by kenneth…which it looks way more user friendly…but with the otherone if we put the same settings its the same thing isnt it.

ps. I don’t have a Twizy…I’m just keep on dreaming :frowning:

Yeah, 72mph was on a slight downhill, the wind noise definitely gets a bit loud at that speed. The tyres are inflated to their upper limits, with rolling resistance at its minimum. Like I said, the car is not really designed to be doing those speeds, especially without windows and doors. Same gear, same everything, the PowerBox does a great job in torque increase. I would not keep that speed up for long though, the battery takes a beating and everything will heat up (gears, battery, electrical system… etc). Aerodynamics has to take into account the mission of the vehicle - such as your design requirements. The Twizy’s mission has always been an urban one and motorways was never really been much in scope. The PowerBox does great on the 0-30mph which is great at intersections, and makes the vehicle more responsive. Make sure you get a Twizy with doors, it does make a difference in both wet-vs-dry and your ability to get additional protection such as windows :slight_smile:

Thank you very much for your help.
Can you address me to some website of used twizy?
If I’ll ever get one I wanna mod the gears.
…- don’t get why they didn’t make it as liquid cooled…well I get it…wasnt ment for Racing :smirk:
Anyways there’s much to do even for reducing weight.
I bet -100kg it’s feasible! :grin:

Well, if the initial reason is energy efficiency, then low rolling resistance tires or at least high tire pressure is the most important modification… in relation to air drag you can also check the bottom of the car and if possiblel make it as uniform, flat as possible…

Right. Like I saw Kenneth and other ppl making their Twizy go like 100kmh or more! At that speed (but I guess at 80 already) a flat bottom will make quite a difference…
But can’t say how much till I do it!!!

Do you know if slick tires make less drag?