Driveshaft weights and loctite

[rgh0]

The cap head hex socket bolts locating the CV's are hard but can be drilled with a good quality drill and correct speed selection and liberal cutting oil use OK. I have done it in other locations but never felt it was needed for the CV's.

cheers
Rohan

[alan.barker]

here's photos
Alan

[alan.barker]

My friend just weighed the MM CVs 6 kgs.
Rotoflex + shaft+bolts 4 kgs.
Elantrikbits 5.1 kgs
So MM CVs are 50% or 2 kgs more.
I understand UJ sliding driveshafts are just under 4 kgs.
Alan

[alanr]

Interesting...
Now if you were cleverer than I you could work out the MM Cv's increased rotational mass/inertia at speed versus the rotational mass/inertia at speed of the Rotoflexes. This would be no doubt work out to be a quite a substational figure.
Maths homework for the weekend?

Alan.

[Andy8421]

Interesting...
Now if you were cleverer than I you could work out the MM Cv's increased rotational mass/inertia at speed versus the rotational mass/inertia at speed of the Rotoflexes. This would be no doubt work out to be a quite a substational figure.
Maths homework for the weekend?

Alan.

Rotational inertia is a function of both mass and distance from the centre line. While I am only speculating, the CVs seem to have a lot of their mass concentrated near the driveshaft, whereas the rotoflex have their mass concentrated much further out. As a result, the difference in rotational inertia is likely to be much less than the simple increase in weight would suggest.
Having said that, (again speculating) I would expect the rotational inertia of the driveshaft is negligible in comparison to the wheel / tyre / disc combination.

This only matters for acceleration or braking, inertia doesn't impact steady state running.

Andy.

[2cams70]

Don't forget the unsprung mass either! It's important to keep that as low as possible. The more mass you have jumping around when the suspension moves the more difficult it becomes to control with springs and dampers and to keep the wheel the wheels in contact with the ground over bumps. You need firmer suspension to compensate.
It's probably more important than the rotational inertia of driveline parts.

That's why you don't fit huge brakes tyres and wheels unless you really need to.

[Andy8421]

Don't forget the unsprung mass either! It's important to keep that as low as possible. The more mass you have jumping around when the suspension moves the more difficult it becomes to control with springs and dampers and to keep the wheel the wheels in contact with the ground over bumps. You need firmer suspension to compensate.
It's probably more important than the rotational inertia of driveline parts.

That's why you don't fit huge brakes tyres and wheels unless you really need to.

Indeed. The Elan was originally designed with inboard rear brakes with the discs and calipers mounted next to the diff for this reason. The problem was that the Rotoflex weren't up to it and they had to move to outboard brakes.

[alan.barker]

Does that mean there were Lugs in the Diff Casting like on Jags.. That would warm up the Diff more which on 26Rs already has a Oil Cooler. Also Air Scoop.
Alan