Passive Rear Wheel Steering?
Skystar
206 and 307 have it too (the 307's system is somewhat different).
What does this system do, and how does it work?
Ben Cowell
"Skystar" <skyst...@bigpond.com> wrote in message
news:aorkdb$5j1$1...@towncrier.cc.monash.edu.au...
It turns the wheels in the opposite direction to the front wheels when under
extreme force. This helps to prevent understeer (when the front wheels don't
turn as hard as you want them to). In order to feel the passive rear wheel
steering, find a tight motorway sliproad and accelerate. I find that a road
turning right gives better feel.
Hope it helps
Ben (1999 Citroen Xsara, yes a 306 in sheeps clothing!)
Skystar
"Ben Cowell" <benc...@NOSPAM.cyberdude.com> wrote in message
news:103503758...@dyke.uk.clara.net...
>
> "Skystar" <skyst...@bigpond.com> wrote in message
> news:aorkdb$5j1$1...@towncrier.cc.monash.edu.au...
> > I know the 306 is famous for its passive rear wheel steering, and I know
> the
> > 206 and 307 have it too (the 307's system is somewhat different).
> >
> > What does this system do, and how does it work?
> >
> >
>
> It turns the wheels in the opposite direction to the front wheels when
under
> extreme force. This helps to prevent understeer (when the front wheels
don't
> turn as hard as you want them to). In order to feel the passive rear wheel
> steering, find a tight motorway sliproad and accelerate. I find that a
road
> turning right gives better feel.
Thanks for that. Does anyone know how it actually works - how do the
cornering forces cause the suspension to turn? I've heard that the wheels
turn in the same direction as the front wheels in some cases, in other cases
they turn in the opposite direction.
"The design of this geometry, and the fine tuning of the suspension bushes,
is such that in the initial stages of a turn, the centrifugal forces create
a small 'rear wheel steer' effect in the opposite direction to the way the
front wheels are being pointed. Then, as the centrifugal forces build up
through the corner, the rear wheels start steering in the same direction as
the front wheels. The result is a more positive 'attack' into the first
stages of cornering and increased stability in the later stages."
This is what I read about an Alfa GTV, curious to find out as to how the
rear wheels suddenly can change to the opposite direction.
Julian Stafford
Skystar wrote in message ...
>Thanks for that. Does anyone know how it actually works - how do the
>cornering forces cause the suspension to turn? I've heard that the wheels
>turn in the same direction as the front wheels in some cases, in other
cases
>they turn in the opposite direction.
Compliance in the bushings and a degree of flex in the components would be
my guess, stick your head under and look, there's no rocket science
underneath. IMO just some wobbly old suspension that the pug marketing boys
are trying to put some gloss on :-)
Julian.
Gary Harrison
Cheers
Gary Harrison.
Ben Cowell
"Gary Harrison" <gaz.ha...@harrisong.fsbusiness.co.uk> wrote in message
news:3DB1C542...@harrisong.fsbusiness.co.uk...
> That's right, but it does work.
>
> Cheers
>
> Gary Harrison.
>
In my opinion, Yes!
Ben
Gary Harrison
Gary Harrison
Chris Barnard
If it's anything like my 305's suspension, it has rear trailing arms that do
look a bit wobbly - not much to look at underneath, but they keep the wheels
vertical over bumps whilst allowing the wheels to lean under cornering.
My Maxda RX-7 Turbo II has an interesting passive rear-wheel steer system
that looks rather complicated (hope it never goes wrong!) - the forces
acting on the wheel during cornering (centripetal force for anyone
interested) make the wheel 'toe-in' on initial turn-in, making cornering
under acceleration more stable and reducing the chance of wheel-spin with
the rear-wheel drive.
Chris.
"Gary Harrison" <gaz.ha...@harrisong.fsbusiness.co.uk> wrote in message
news:3DB1EA5D...@harrisong.fsbusiness.co.uk...
DervMan
> news:aorkdb$5j1$1...@towncrier.cc.monash.edu.au...
> > I know the 306 is famous for its passive rear wheel steering, and I know
> the
> > 206 and 307 have it too (the 307's system is somewhat different).
> >
> > What does this system do, and how does it work?
>
> It turns the wheels in the opposite direction to the front wheels when
under
> extreme force. This helps to prevent understeer (when the front wheels
don't
> turn as hard as you want them to). In order to feel the passive rear wheel
> steering, find a tight motorway sliproad and accelerate. I find that a
road
> turning right gives better feel.
Yeah - it's usually a pretty simple system to engineer, and many cars have
it - when VW launched the mark three Golf, back in the early 1990s, it also
had passive rear steering. Who knows if it helps, because mark three Golfs
are not renowned for being nimble handlers.
I distinctly remember reading a road test report of the new mark three Golf
1.4 compared with the (still new) ZX 1.4, and they detailed how the cunning
rear steer arrangement works, but I cannot locate the magazine . . . :-(
--
The DervMan
www.dervman.com
DervMan
> "DervMan" <der...@hotmail.com> wrote in message
> news:aotka9$ppsco$1...@ID-136275.news.dfncis.de...
[snip]
They might have!
Actually, I think you're right, which would explain why they didn't shout
about it with the mark three.
--
The DervMan
www.dervman.com
G.T
> underneath. IMO just some wobbly old suspension that the pug marketing
boys
> are trying to put some gloss on :-)
LOL ! I don't think it was the case. BTW, first pugs having a rear steering
(less developped than on ZXs & 306s of course) were 405 (SR ?) SRi & Mi16. I
had a look once on mine, it's based on a multiarm supension design (with,
still, a classic pulled arm & almost horizontal shocks).
You can feel it when you sit at the back, and taking fast a "S" (called
"lacet" in French) : by this you feel the rear train seeking (and finding)
its way. Quite impressive when you don't know that, but sooo good when
driving :-)
Regards,
G.T (sometimes uses a '88 405 SRi, THX Mum)
g....@worldonline.fr
mi...@ironmaiden.com
205 Diesel & turbo-Diesel : http://205d.fr.st
Georg Richter
aotp18$pdb0e$2...@ID-136275.news.dfncis.de...
> > I thought they introduced it with the Mk2 Golfs?
>
> [snip]
>
> They might have!
>
> Actually, I think you're right, which would explain why they didn't shout
> about it with the mark three.
Even the Mk1 Golf has had such kind of, but it was mostly working sometimes
later after buying, if the tin was rusty ;-)
--
Georg O.F. Richter
alias Hourdi
hourdi_@_t-online.de