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mumford axles and roll centre?
daniel mason - 5/7/13 at 07:55 PM

please could someone describe to me exactly how a mumford rear axle works? how it lowers roll centre, and why many believe its a better race setup than IRS?
Cheers all


deeceee09 - 5/7/13 at 08:12 PM

Is it the same as Arthur Mallock's WOBLINK live axle? If so have a look at Alan Staniforth's Race & Rallycar Source Book. On the other hand it may be nothing like it.


Slater - 5/7/13 at 08:14 PM


deeceee09 - 5/7/13 at 08:16 PM

OK it's not the same but have a look here http://qrgarage.ca/2010/05/30/mumford-linkage-for-lateral-axle-placement/


britishtrident - 5/7/13 at 08:16 PM

The Mumford linkage t is just another modification of Mr Watt's parallel motion to give a lower roll centre, an earlier variation on the Watts linkage is the Mallock Wobble link (aka Woblink)
The bigest advantage of the Munford linkages is the mountings at the chassis end are symmetrical and there is virtually zero variation of roll centre location over a wider range of travel.

It is only useful if you are using a live rear axle or a De Dion.
Because of unsprung weight (and where the unsprung weight is distributed on the axle) even the best live rear axle is never as good as a half-decent IRS but a good De Dion is as good as a decent IRS as the advantages and disadvantages of each are finely balanced.


mark chandler - 5/7/13 at 08:19 PM

Thinking about this as a wide car axle is confusing, imagine the axle as a rectanglular box with the pivot point in the centre point (watts linkage/panard rod) now squeeze the sides in so it becomes a very tall thin structure.

Now imagine moving the pivot point lower (mumford axle) it becomes harder to push over, does that makes sense?


deeceee09 - 6/7/13 at 04:30 PM

Think the WOBLINK is attributable to James Watt, Maurice Olley and Donald Bastow.


britishtrident - 7/7/13 at 07:20 PM

Maurice Olley invented most things we use in car (and aircraft) suspension, the rest we can credit to Fred Lanchester.


daniel mason - 7/7/13 at 08:00 PM

there was a mallock mk18 with a bog standard hayabusa at harewood today. driver had only had 1 previous visit to the venue and he ran a 56sec run in first round.
to compare it was miles faster than all the caterhams with 1600busa, 2.3 duratec. westy 1400 megabusas and the best i saw duncan cowper do in his dax was over 60 secs (although on road tyres)
i was generally amazed!