twin link question

[BDA]

I'm glad that helped you! Actually, as I remember it, Richard assembled it for me. It was early in the development of the rear disc system and I don't think he had a set for the TCS so he replaced my uprights and radius arm with TC parts and put most of that together for me. So he drilled and tapped the upright.

[jbcollier]

You can’t tap the upright in that area.  It’s really, really thin.  Just holes with bolts, washers and nuts.  You have to do it while it’s disassembled as that’s the only way in.

[BDA]

I’m glad to know there’s a nut behind it. That’s a lot better than what I had assumed!

[califkid_66]

i like this bracket to it’s another design used the four bolts seems simpler

[EuropaTC]

That's a neat idea. I've wondered on and off about making a twin link and thought that welding a bracket in front of the driveshaft to the trailing link might be the best way to go.

If there's enough strength in the bolts into the upright that looks a better idea because you'll be able to adjust the height with spacers to get an exact copy of the inner UJ movement. If the other end is similar, it should result in very little movement, if any, on the splines once the pin is removed.

Good find.....  is it anyone on here ?

Brian

[GavinT]

Yes, Brian, that's Richard Mann's car.

[BDA]

Richard developed a clever twin link system where the inner upper link is attached to the tranny. A friend of mine is using it on his car and rather than using a CV joint, he's just letting the U-joint yoke on the output shaft slide. He tells me Richard had blessed it and I think JB recently posted a similar sentiment so I presume it'll be alright.

Richard more fully described his setup here: http://www.lotuseuropa.org/LotusForum/index.php?topic=1724.msg15757#msg15757

[SwiftDB4]

Letting the inner u joint end of the driveshaft slide on the trans splines is OK. Have over 20K miles on mine. I fabricated my own twin link similar to Banks. Was very careful to parallel the driveshaft movement with the upper link and rod ends. I did use self tapping screws on the 2 fasteners that go into the upright body. Metal thickness on mine is .300". No cracks or loosening yet.

[BDA]

I suggested using moly grease on the output shaft to my friend who implemented Richard Mann’s scheme. What is your experience, Swift?

[SwiftDB4]

Yes I use moly grease on the splines. I would estimate movement on the splines is less than 1/8" if you get the upper link and rod ends parallel to the driveshaft.

[califkid_66]

found this twin link i like the way it is bolted to the transmission i wonder if this would work ok
you don’t need much fabrication don’t have to relocate the coil springs but using original driveshaft without roll pin might put a little stress on engine and transmission support what do you guys think

[TCS4605R]

It looks like a good alternative to Banks twin link.  Do any drawings exist for the mounting plate?

Tom

[BDA]

That was taken from a strategy of Richard Mann's (our own Lotus 47). I would say design but it would change a little depending on which tranny you had. The idea is to stay very close to the original geometry.

I think there was a recent thread where it was decided that CV joints weren't actually required and the inner u-joint could be left unpinned to handle the plunge in the half shaft.

Richard did a writeup of it here: http://www.lotuseuropa.org/LotusForum/index.php?topic=1724.msg15757#msg15757

[jbcollier]

I'd like it better if it exactly matched the position of the halfshaft.  This is a little high which will induce more movement of the yoke on the spline if you stay with the original half shafts.

[califkid_66]

what i meant was doing a simular set up aligning the pick up points to follow the same radius as the original half shaft the difference would be that the inner bracket would be bolted to the transmission instead of the frame
on regular twin link the bottom trailing arm are tied to the transmission top one to frame
this way both would ne bolted to the transmission