Plus 2 UJ Shaft Conversion
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I'm overhauling the rear end of my Plus 2 and have to decide what to do with the drive shafts. Original plan was to convert back to Rotoflex (I have bought second hand shafts but not the doughnuts yet). However on inspection these UJ shafts are in good condition. I have no idea if these were specifically made for the Lotus or have been converted from something else. Are there any reasons why I shouldn't retain this setup, apart from originality?. I should add I have never driven the car so can't comment on how these shafts perform.
- 111Robin
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Lots of threads on here about the use of hook joints and sliding splines or CVs in place of Rotoflex. Worth doing a search.
If you do decide to reuse them, it is important you put the splines back together so the 'ears' of the hook joints at either end of the shaft are in the same plane as each other or you will get torsional vibration. Very clear video on youtube. Colin has taken care of making the input and output angles about the same, but it is down to you to get the phasing right:
https://www.youtube.com/watch?v=gmV4qwLfOMY
I came across this TTR instruction sheet that illustrates the alignment required:
If you do decide to reuse them, it is important you put the splines back together so the 'ears' of the hook joints at either end of the shaft are in the same plane as each other or you will get torsional vibration. Very clear video on youtube. Colin has taken care of making the input and output angles about the same, but it is down to you to get the phasing right:
https://www.youtube.com/watch?v=gmV4qwLfOMY
I came across this TTR instruction sheet that illustrates the alignment required:
68 Elan S3 HSCC Roadsports spec
71 Elan Sprint (still being restored)
32 Standard 12
Various modern stuff
71 Elan Sprint (still being restored)
32 Standard 12
Various modern stuff
- Andy8421
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I note that the flanges on mine have four bolts, the performance unlimited ones look like they have three. Also, mine have one larger "master" spline so there is only one possible orientation for assembly. I haven't yet checked what alignment of the Uj's this results in. Maybe these are a DIY conversion ?.
- 111Robin
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There has been discussions on quality of rubbers (too many kids being born) and donuts in the past. Not sure who is making the good ones, recall all the suppliers use the same ones. I went CV because of this.
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
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Find out where the limits are, and start from there
Love your Mother
Earth
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h20hamelan - Coveted Fifth Gear
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111Robin wrote:I note that the flanges on mine have four bolts, the performance unlimited ones look like they have three. Also, mine have one larger "master" spline so there is only one possible orientation for assembly. I haven't yet checked what alignment of the Uj's this results in. Maybe these are a DIY conversion ?.
I am an Elan not Plus2 man, but I thought the Plus2 had the same arrangement as the Elan - the output shafts of the diff and the shafts through the rear struts have 3 arms to line up with the Rotoflex joints. How did your driveshafts line up with 4 bolts?
68 Elan S3 HSCC Roadsports spec
71 Elan Sprint (still being restored)
32 Standard 12
Various modern stuff
71 Elan Sprint (still being restored)
32 Standard 12
Various modern stuff
- Andy8421
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Andy8421 wrote:111Robin wrote:I note that the flanges on mine have four bolts, the performance unlimited ones look like they have three. Also, mine have one larger "master" spline so there is only one possible orientation for assembly. I haven't yet checked what alignment of the Uj's this results in. Maybe these are a DIY conversion ?.
I am an Elan not Plus2 man, but I thought the Plus2 had the same arrangement as the Elan - the output shafts of the diff and the shafts through the rear struts have 3 arms to line up with the Rotoflex joints. How did your driveshafts line up with 4 bolts?
You should have some adapter plates somewhere, the assembly looks like this:
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
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pharriso - Coveted Fifth Gear
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Andy8421 wrote:111Robin wrote:I note that the flanges on mine have four bolts, the performance unlimited ones look like they have three. Also, mine have one larger "master" spline so there is only one possible orientation for assembly. I haven't yet checked what alignment of the Uj's this results in. Maybe these are a DIY conversion ?.
I am an Elan not Plus2 man, but I thought the Plus2 had the same arrangement as the Elan - the output shafts of the diff and the shafts through the rear struts have 3 arms to line up with the Rotoflex joints. How did your driveshafts line up with 4 bolts?
Both output shaft and outboard shaft have 4 bolt flanges on them to interface with the UJ flanges. I haven't yet looked at them in any detail to see how they've been manufactured. This is what makes me think it's a DIY job.
- 111Robin
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111Robin wrote:Both output shaft and outboard shaft have 4 bolt flanges on them to interface with the UJ flanges. I haven't yet looked at them in any detail to see how they've been manufactured. This is what makes me think it's a DIY job.
Are you sure you haven't left the adapter plates on the Diff output shafts & the Hub shafts?
Please post a picture of either / both...
Phil Harrison
1972 Elan Sprint 0260K
1972 Elan Sprint 0260K
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pharriso - Coveted Fifth Gear
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pharriso wrote:111Robin wrote:Both output shaft and outboard shaft have 4 bolt flanges on them to interface with the UJ flanges. I haven't yet looked at them in any detail to see how they've been manufactured. This is what makes me think it's a DIY job.
Are you sure you haven't left the adapter plates on the Diff output shafts & the Hub shafts?
Please post a picture of either / both...
I'm not sure, I just pulled the shafts on Friday then had to leave it. I'll check and take photos next week.
- 111Robin
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I've seen the opinion expressed that while donuts are fine on en Elan, they're not really ideal on the heavier Plus 2. I can't offer any perspective on that since my Plus 2 was converted to CVJs by a previous owner.
1970 Elan Plus 2 (not S) 50/2036
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
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The Veg - Coveted Fifth Gear
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Yes I can imagine there's more tendency to wind up the doughnuts with the inertia of the heavier car although conversely it would be less harsh than a UJ setup. I have yet to decide which way to go although dubious quality of current elastomeric products will probably sway my decision. I don't have the budget for a full CV setup so hopefully I can use what I have, as long as it has been well engineered.
- 111Robin
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Since the Plus 2 is something of a 'gentleman's express,' the more refined performance of the CVJs seems like a natural fit, so start saving your pennies to eventually get them!
1970 Elan Plus 2 (not S) 50/2036
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
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The Veg - Coveted Fifth Gear
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