Talk:De Dion suspension

Name Change?

This is the first I've been to this page in a while, and I've noticed what appears to be a name change. It's surely a translation of the German term, "De-Dion-Rohr" -- but I've never heard of this thing in English referred to as a de Dion tube. It's just a De Dion suspension. Yes, we've got the problem in the English language of the axle-tube confusingly called the "axle" while the axleshaft, properly be so called, is neglected, but I've never seen the De Dion mechanism referred to as a tube. There is no (axle?) tube in the modern examples I've seen, except for Rover's, which does not envelop the axleshafts.
Perhaps, like the magazine Scientific "American", Wikipedia has been sold to the Germans. Sobolewski 16:22, 14 May 2007 (UTC)

The De Dion tube is just one part of a De Dion suspension; I don't have a clue why this was renamed either. I vote for renaming it back. Alex 16:34, 15 May 2007 (UTC)

I agree, the De Dion tube is just a component of De Dion suspension, and so I also vote for renaming it back KingDoorknob 21:52, 10 June 2007 (UTC)

How do we rename it? There's a ton of stuff that links here Special:Whatlinkshere/De_Dion_tube Alex 22:21, 10 June 2007 (UTC)

I don't know how to rename it but agree that tube is wrong, in English. Greglocock (talk) 17:25, 26 January 2024 (UTC)

Done Greglocock (talk) 01:17, 12 February 2024 (UTC)

dynamic response

What is meant by "Compared to a fully independent rear suspension the ability to refine the dynamic response of the vehicle is somewhat limited."? With De Dion suspension, all suspension parameters can be changed as in any IRS; static camber, rollcenter heights, anti dive/squat and any damping or ride/roll rate just as in any independent suspension. With De Dion there is no virtual front view swingarm or instant center so you can't change the camber curve (there is no camber change, its perfect except for one wheel bump). I don't think De Dion suspension has a "limited ability to refine dynamic responce". —Preceding unsigned comment added by Bdsmith21 (talk • contribs) 19:30, 27 February 2008 (UTC)

Well, you often do want to increase camber curve, so that is one strike. Next, you have a problem with toe compliance under braking and traction, which can be ameliorated at some cost, but not eliminated. That is if one wheel has more grip, both wheels steer the same way. An IRS can easily be arranged not to steer at all. It's not a terrible suspension, but it is as expensive as an IRS, and not as good. I wouldn't mind working on one some time, the nearest I've done is a twist beam.Greg Locock (talk) 01:32, 28 February 2008 (UTC)

Ford Ranger

Isn't the Ford Ranger EV in the picture using Watts linkage instead of a de Dion-syspension? at least the same picture is used in that article and it the structure looks like in all the watts linkage diagrams... K-carsten (talk) 02:40, 13 January 2010 (UTC)

The article mentions that you can use a de dion with a watts. Greglocock (talk) 03:05, 13 January 2010 (UTC)

non-independent

Why is this referred to as "non-independent" suspension? With u-joints at both ends of each axle, the wheels are free to move independently, although tied together with the DeDion linkage. I agree with others who've questioned the word "tube." A DeDion suspension can be designed using linkage formed from structures other than tubes. From that perspective, the article's title is somewhat misleading, in that it (as written) refers to only one component of the suspension design which may or may not take the shape of a tube.
Bruno (talk) 18:29, 16 December 2011 (UTC)

With u-joints at both ends of each axle, the wheels are free to move independently

They aren't. The stub axles are rigidly fastened to the de Dion tube, just like a rigid live axle. The dynamics of a de Dion are just the same as a live axle, not independent suspension. The only difference is that the differential and final drive are chassis mounted, so they're not part of the unsprung weight. A de Dion exists for its weight saving, not for any change in geometry. Andy Dingley (talk) 19:43, 16 December 2011 (UTC)

Named after...

The article currently claims: "The de Dion tube was named after Comte Jules-Albert de Dion"
I find that unlikely. I bet it was a later attribution by engineers studying the field of automotive suspension, and was named after the conveniently shortened name of the manufacturing company.
Unfortunately I can't check the given source myself.
--BjKa (talk) 10:45, 25 January 2024 (UTC)

Enthusiasm and Setright

Some accurate observations have been completely eliminated and replaced by Setright's enthusiasm for the device. I'd point out that Setright's expertise lay elsewhere, and have never seen him quoted as an authority on suspension design in non populist literature. Quite why the Poms were so keen on the things is always a mystery to me, given that the thing is as expensive as an IRS, and if anything more difficult to get right for a production car. Greglocock (talk) 05:52, 4 September 2012 (UTC)

Which are?

I don't know if Setright was enthusiastic for De Dions, if he was enthusiastic for them because Bristol used them, or he was only enthusiastic for Bristol's implementation of them. How did he feel about Aston Martins? I think he had a point though - the value of a De Dion isn't today, when a monocoque body with excellent spring metallurgy can have effective IRS, but back in the '50s & '60s when IRS often just didn't work right without some awful side effect in an extreme condition. For a decent road surface (and Setright wasn't an off-roader) the De Dion was a very good choice and remained so for a long time. Just look at Chapman's long-term use of the things.

We might better options today, but not so much back then. Andy Dingley (talk) 09:48, 4 September 2012 (UTC)