Egress outdrive question

[Saito2]

Someday, I may get to run my re-re Egress, if the ground ever dries out a bit or the rains stop but until then, I remembered a concern I had during assembly. From what I remember, the diff outdrives are not positively attached to the diff in any real way. It appears that a spongy bushing (BB37) inserted in the outdrive with the dogbone end of the universal shaft pushing against it is the only thing keeping them in. Has anyone had any issue with them popping out or anything (particularly when turning?). Probably just being paranoid . 

[Thommo]

Hi Mate,

There is actually a complicated answer to this but the short version is NO, the out-drive will never pop out.

The norm is for the lower suspension arm to hinge below the out-drive.  However unlike just about every other buggy on earth, the Egress (Avante) has the drive shafts on exactly the same plane as the lower suspension arms.  The front lower suspension arms even have a little arch for the drive shaft to pass through to achieve this.  Check out how the hinge for the lower suspension arm and the out-drive are in line with each other on the front gearbox for example. 

The result is that the distance between the out-drive and the hub does not alter during suspension travel..... so the gap never gets bigger, hence the out-drive and the drive shaft stay nicely in place.

[Saito2]

Thanks for putting my fears to rest. I always thought the Egress/Avante inner arm pivot point was pretty unique being in line with the driveshaft's output. I never put two and two together. Makes sense. Thanks!

[Thommo]

I think T was trying to be clever with their engineering, steering and suspension geometry with the Avante and Egress but it turned out to be over engineered and never caught on.  You can make them handle pretty well in loose dirt / gravel etc but the Top Force was the natural and logical progression.  You can see it with the Jamie Booth Egress mods that drop down the lower arms for a more conventional set up.   

[Saito2]

I always found it interesting from an evolutionary perspective that Tamiya went from the complexity of the Egress to the simpler, more mainstream (and in the end, better performing) design of the Top Force. Jamie Booth's car is a fascinating transitional piece of engineering with that simpler suspension (with more caster too) cleverly adapted to the Egress platform.

[ruebiracer]

I had the same surprise while recently purchasing an Vajra for parts from Tamico. Thought about using the diffs and shafts for my Vanquish vintage runner, and was a little surprised about a missing Fixation. To stop possible wandering and wear, I will probably use the AW grease when assembling the outdrives. Together with the foams, there shouldn´t be any problems then. But Thommo made it totally clear, never really thought about this special Avante design feature. But I was always a fan of the ground clearance of these buggies. It´s almost like having portal axles.