Lotus Elan and Lotus Elan Plus 2 Forums

........................any experience fellas???? i'll give em a call a bit later HOWEVER there may be some insight regarding these bits RIGHT HERE?? alpine and even scottish sandy muchas gracias PS: i wanna keep my FRAME nice and stiff, so the rotoflex suit me and my pal just fine -- even if i race her: i'll risk the 1/10th i loose, as first of all the 1st curve is to master!!

From the picture these appear to be identical (apart from size) to one that is installed in one of my other cars. In that car it is fitted between the diff and the propshaft and it is handling 450bhp and 400lb ft of Torque. It is a VERY stiff device. By all means try one but I don't think it will have anything like the flexibility to cope with the alignment changes.

....are they not available in different shore ratings (as per their metalastic bushes)?

It's much less stressed in a propshaft application. The angle change is less and the torque input is prior to it being multiplied by the differential ratio. The BHP figure is unimportant.

....................... i'm hoping to see some information from a USER! if someone exists sandy

2cams70 wrote:It's much less stressed in a propshaft application. The angle change is less and the torque input is prior to it being multiplied by the differential ratio. The BHP figure is unimportant.

Yes, so the question I have for people who like the idea of rubber bands in the driveline is: Why not just use them on the propshaft, where they have a more effective way of eliminating shock in the rest of the driveline than on the output shafts? That's what BMW did, at least on the 1600 and 2002 (the last ones I played with.) And I believe I was the first to replace them, at over 100,000 miles, though that service interval did cost an ear on the propshaft due to PO neglect. The output shafts used CV's (and they were still in fine shape).

Much heavier car, similar horsepower and torque.

I had a BMW 2002tii and it used to eat propshaft rubber doughnuts every 10-15000miles!...Superb machine though so one couldn't help but give it some boot!

Robush listed the Rotoflex coupling, which, assuming you buy the right one is the coupling used on the Elan. Be sure to get the one with interleaving.

alanr wrote:I had a BMW 2002tii and it used to eat propshaft rubber doughnuts every 10-15000miles!...Superb machine though so one couldn't help but give it some boot!

Yes they are nice but a bit too refined for my tastes at least!! - much like a modern era car. The steering precision is not quite up there with the best either. I've pulled apart a few BMW's and they still use rotoflex couplings in the propshaft - up until the early 2000's at least (I haven't checked out the latest ones). They use them right throughout the range from the poverty pack 4 cylinder models up to the beefy 6 cylinder versions.

I believe they still use them in BMW. My 2002 e39 has one and can't see a good reason why they'd suddenly decide they weren't needed any more.

If you are really interested the part diagrams are available at realoem.com so you can go and check for any BMW new or old.

The BMW uses the Guibo joint, which is not the same thing as the Rotoflex coupling used by Lotus. That is not to say that some BMW owners may have used the Rotoflex as a replacement, but it is not really the same thing. The Guibo coupling is not intended to be used with the high angle that the Rotoflex was designed for. Outside of British cars using the Rotoflex type coupling, I have owned three Alfas, which used a Rotoflex like coupling on the drive shaft