Bluebottle wrote:I don't know much about the Sierra issue other.
These things happen regularly and it isn't always the aerodynamicists fault. Sometimes some bright spark decides he doesn't like that bit of trim being there or the shape of the wheel arch etc and buggers the airflow without realising.

I am not arguing that he isn't to blame - I don't know.

You also get unexpected side afffects from the shear complexity of what the air is doing and some carefully thought out flow management doesn't work because something else generates greater/weaker forces somewhere else or something only happens in a certain situation (folloing a HGV with a specific side wind and airspeed).

I used to be a motor machanic back then and we got the trade articals about it but I found this on wiki

http://en.wikipedia.org/wiki/Ford_Sierra
Early versions suffered from crosswind stability problems, which were addressed in 1985 with the addition of "strakes" (small spoilers), on the rear edge of the rubber seals of the rear-most side windows.

I look forward to reading more - thanks for putting the time in

Back then there was also a fashion for aftermarket spoilers for a "sporty" look (("spoiler" because it spoils the airflow )
A lot of these were really dangerous and caused a lot of lift at the back of the car. Some were recently pulled off the American market after being proven to contribute to lethal accidents in VWs.

It takes a lot to get this stuff right and itis one of the differences between an expensive bike and a cheap one. Manufacturers like BMW spend time in the wind tunnel getting the dynamics right at various angles of attack/crosswinds.

It gets more complicated on a fast bike because when you lean into a corner the lift that was acting sideways becomes lift acting upward - reducing your tyres grip.

As a side point - the average drag actually went up when they introduced the enclosed bodywork to streamline race cars in the thirties. Older cars had narrow tapered bonnets with the wheels outside (typical vintage car shape) and that channeled the air much better than the "modern" enclosed shapes.

Aerodynamics isn't worth a damn unless you also consider the great fat oaf astride the vehicle and stop him sitting upright like he's dumping on a birthing chair.

And here I'm laughing at: Ludicrously contorted whinemongers in world superbikes ("My bike is soooo slow" - no, it's because your aerodynamicist is fat, and shit), the hideously highsided macadam munchers in Moto GP (front end chatter is caused by weight transfer you fucking idiots) and those buffooning ballet dancers in British Super Bikes (the lack of drive out of corners is because your motorcycle is rotating around the rear swingarm pivot as your designer doesn't understand basic rotational physics).

On that basis I'd have to say the Piaggio's new X10 is a remarkable piece of design. And about 7% of the way toward a truly aerodynamic vehicle. Well, it's a start. But with an Italian lunch...

The Monotracer sets the standard that nothing else can match
Cd x A = 0.18, Cd = 0.15
Proven in the VW windtunnel

As I said right at the beginning, Jo Public sometimes uses "aerodynamic" to mean "low drag" but the two things aren't the same.
Dynamics is more than drag and is worth rather a lot in vehicle R&D and to Muppets wanting more comfort on the bike they've got - which is going to be my next bit.

I want to mention the problems with the Monotracer toward the end, I want to introduce a bit more about the workings first.

Hurling unqualified abuse doesn't get any of us anywhere.

It's that time of year again!

Citycom 300i topless - before and after...

http://www.blogcdn.com/translogic.aolau ... 329687.jpg" onclick="window.open(this.href);return false;


That yellow thing with a wheel at each end is me !!! in my day glow suit engulfing my scoot lol

anonstarter wrote:It's that time of year again!

Citycom 300i topless - before and after...

Looking snappy Mr Anon

Looking forward to our Brixham trip

Raven

I must admit I always prefer low screens to tall ones which seem to create buffeting and noise around the head..
When I had an GSX1100 with the electric screen. The best and quietest setting was when the screen was set in the lowest position.

wozza wrote:I must admit I always prefer low screens to tall ones which seem to create buffeting and noise around the head..
When I had an GSX1100 with the electric screen. The best and quietest setting was when the screen was set in the lowest position.

aggree 100 percent .
Same as riding with visor open
Same phyics