Lotus Elan and Lotus Elan Plus 2 Forums

Hello,

As some may know, I'm completing some testing on improved rotoflex couplings using some improved materials/designs. To complete testing, I want to test the couplings at the full range of deflection that the doughnuts are subjected to in real world elan use prior to installing. Although this may vary between owners cars, can someone verify some angles of the driveshafts (i.e. difference in height from one coupling at diff to coupling at rotor) at ride height and at full droop to capture a full range of deflection for test. I know that full droop is extreme and not the norm unless elan is airborne or on a lift but still needs to be part of testing for longevity.

Thanks for any help and I appreciate this forum.

Thank you

David D.

Hi David.

I think you are doing the correct thing.

Just to be clear, are you asking for the difference in height between the centerline of the differential output shaft and axle center line?

Bill

Yes,

The difference between The cl of diff output shaft and outboard end of axle (rotoflex mated to rotor) would be helpful on full droop and ride height. This way I can build a jig to simulate the extremes of angles encountered. I'm very excited as it seems I've achieved a great bond between the material and metal interleaves.

Thanks!

The outer shaft centreline is approx. 20 mm below the inner shaft at normal ride height
Full droop travel is approximately 70mm down from there
This is according to the drawing in section D of the workshop manual and corresponds to my S4

cheers
Rohan

This is great,

Thank you much!

Did you not think to look in the workshop manual? No offense but if you are aiming to make some exciting technological breakthrough, which Lotus owners have been waiting for since 1964... might that not have been your first port of call?

Just saying.

David,

I went down the CV joint route.

I was wary of relying on the drawing in the manual, so took my own measurements, and came up with an angle of 22degrees & 45seconds between full bump and full droop.

Hope this helps, and good luck with the replacement couplings. My attempts to find a good quality replacement Rotaflex all stumbled on an economic quantity.

Richard Hawkins