ROTOFLEX QUESTION

PostPost by: garyeanderson » Tue Oct 23, 2012 3:57 pm

OK here are two non-interleaved donuts, the one on the left is probably an original out of a 65 Elan that was last on the road in 1969, the one on the right was bought new in 1992 and was installed but never driven, the chassis was broken up for parts.
rotoflex couplings.JPG and


as far as the other sub topics go, nothing is fool proof, that said somethings will break and others will be broken. You generally hear/remember the bad, the good comes and goes quite quickly. I bought Ray's (RD Ent) back in 1996 and have been using them since, I think the price was just over $1000 including the diff output shafts. I did tear a boot early when the wheel was at full droop on jackstands and I rotated the wheel (lesson learned). I replaced the boot and bought 2 as I like to have spares, I still have it in the box 15 years later. There are things that you can do to limit droop, wire rope and pinch couplings will do the job, Rohan has written about them in the past. The rubber issue seems to be a real one and has crept into the forum 3-5-7 years ago, seems like none of the parts have been exempt. I do not know if those parts are gone or purged from the supply chain. all one can do is be leery and inspect on a regular basis. New interleaved donuts were $100 or more the last time I inquired back in the spring of this year, I would not want to spend that kind of money only to have one fail and flail about bending the the doglegs at the rear of the chassis or busting a nice sized hole in the fiberglass or both. The choice of what to do is up to you and you get to live with the consequences what ever they are. I installed a set of interleaved donuts that I bought back in 2004 for $50 each, I will keep an eye on them as thats about all I can do. The other Elans that I have will need to have something and that something is still unknown to me at this time, I hope that the problems are resolved soon or have already been resolved. It will take some time to know anything for certain. :(

Gary
User avatar
garyeanderson
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 3391
Joined: 12 Sep 2003

PostPost by: gearbox » Tue Oct 23, 2012 4:52 pm

RogerFrench wrote:The Lobro shafts I've seen here, as marketed by RD Enterprises, for example, are quite a bit different from, and more expensive than, those sold previously by Sue Miller etc.

Look here http://www.rdent.com/ select Elan Parts and scroll down.


Not sure how we got on to CV shafts when I was just asking about Rotoflex dating, but I'm game. From what i see, they appear to be the same. Just that RD sells them with the diff output shaft. Same shaft, same Lobro CV's and same aluminum adaptors of sorts. Just the inboard side on the RD, he has attached the diff output shafts directly. But the failure was to the CV's from what I have read. If it is just the boot breaking when Jacking, like what Piss-ant describes, well that is easy to avoid now that we know. But from what Sue says, it's the new batch of Lobro CV's that is the culprit as none of her early ones failed, but the last batch all failed. She states that Lobro had changed their design to make it more efficient (i.e. cheaper) and has no intentions of reverting back. I did see some time back an Aussie company making these, and they claimed to have "Blueprinted" the CV's by polishing the joints among other things. Maybe that might work. But from what I have heard, the new CV's just don't work anymore much like the rubber on the donuts. And at $1500 a pop, that's a big gamble. Who voted for clean air and water anyway lol.


Sue Millers CV's
lotuscv.jpg and


RD CV's
cvelan1s.jpg
cvelan1s.jpg (22.07 KiB) Viewed 1576 times
gearbox
Third Gear
Third Gear
 
Posts: 396
Joined: 12 Mar 2012

PostPost by: Fred Talmadge » Tue Oct 23, 2012 6:16 pm

Here is a link talking about the shelf life of various eleastomers. http://www.oringsusa.com/html/shelf_life.html
I would guess the originals were made from butyl rubber, neoprene or maybe NBR.
User avatar
Fred Talmadge
Fourth Gear
Fourth Gear
 
Posts: 666
Joined: 24 Sep 2003

PostPost by: cabc26b » Tue Oct 23, 2012 6:20 pm

I have and am currently running the UJ's on both track and street and have not found them to give a problem. The kit from TTR is robust , add the steel axles and hubs and short -travel Koni's and you supposedly have life time peace of mind -

I also run the do-nuts and if you are diligent and not abusing them ( with too much horse power or too careless driving) they don't give trouble and I would have to say for casual use they deliver a really nice experience.

George
cabc26b
Fourth Gear
Fourth Gear
 
Posts: 954
Joined: 21 Sep 2003

PostPost by: ceejay » Tue Oct 23, 2012 9:09 pm

Hi Guys.
Time for me to chime in here. With our CVDS conversion there is absolutely no need
for suspension limiting straps, cables, or whatever.

The CVs (GKN Lobro) on our conversion wont lock up....yes, we carry out a special
mod, which is not visible and this mod totally eliminates the chance of any lock up.
(Providing strut rod lengths are standard)

(The mod does take time to do, and does add cost to the product but it also
means you are buying piece of mind).

Also we have not been notified of any problems with boots that have failed, we
have customers all over the USA, Canada, UK & Europe who run our conversion
on elan S1-S4 and the +2 elan who are all very happy with our product... reading the
testimonials on our web site will tell you that also.

GKN Lobro are leaders in the CV production game, in my opinion they are the
best, it is possible to source CVs made in China and other countries but they
are rubbish compared to GKN.

To be honest I fail to see what the inner fear is about making the change to
CV DS, I have been running same on my elan S2 since 1986.... with no problems.

There are elan owners who race and do autocross with our shafts fitted
and they have stood up to the punishment.

CVs will transmit upwards of 280 - 300HP.... now there is no normal elan
around that puts out anywhere near those figures. The major thing that
makes the elan quick is the power to weight ratio.

Sure, to make the change to CVDS will cost you some money, (Maybe that is
the fear) but the cost will be long forgotten when you realize how much better
your elan drives, and that you have found worry free motoring... well, as far
as the drive line goes anyway.
Col
http://www.elantrikbits.com
ceejay
Fourth Gear
Fourth Gear
 
Posts: 623
Joined: 27 Mar 2007

PostPost by: ardee_selby » Tue Oct 23, 2012 11:27 pm

piss-ant wrote:OK here are two non-interleaved donuts, the one on the left is probably an original out of a 65 Elan that was last on the road in 1969, the one on the right was bought new in 1992 and was installed but never driven, the chassis was broken up for parts.
rotoflex couplings.JPG


Gary


The right hand one looks same as the ice cream van item that Mr. Hare found recently:

http://www.icecreammachines.co.uk/80395 ... 4171&ack=9

I mis-read the marking as "SLK" but actually it's clearer in your photo...it's SUK. Referred to in Imp circles as "the dreaded SUK type"...!

Cheers - Richard
ardee_selby
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2197
Joined: 30 Sep 2003

PostPost by: gearbox » Wed Oct 24, 2012 3:47 am

ceejay wrote:Hi Guys.
Time for me to chime in here. With our CVDS conversion there is absolutely no need
for suspension limiting straps, cables, or whatever.

http://www.elantrikbits.com


Hi Ceejay;

Yes, those are the ones that I had seen with the modified CV joints, thank you for bring it to our attention. The write up seems very impressive and convincing. How long do you warranty the product for? Also, It appears that the CV's, while off the shelf Lobros, have been lightened, modified, and polished by you, yes?. When they fail as all CV's will eventually do, how much would a replacement set cost?
gearbox
Third Gear
Third Gear
 
Posts: 396
Joined: 12 Mar 2012

PostPost by: ceejay » Wed Oct 24, 2012 4:36 am

Hi Gearbox
When you say fail, I guess you mean wear out, because with the power that an elan
feeds into the drive line you probably wont ever break any CVs.... but a totally brutal
elan driver may inflict some damage with long term abuse, but my guess is there
are few elan drivers around like that today.

So to answer your question re warranty, if you had a problem within the twelve
month period, we'd oblige with replacement parts, but on past experience which
stretches back more than two decades there has not been any breakages reported
to us.

Id be surprised if a replacement CV set was ever required, the CVs will likely outlast
your elan, but any replacement cost would be based on a per unit CV cost (at the time)
and whatever other costs were involved, I'm not being evasive re cost, just that
it is impossible to predict into the future.

The GKN Lobro CVs are machined to reduce weight, and lightly polished for free
running.

The conversion is very easy to fit and simple to service and maintain, and if
for some reason you ever wish to remove the CV conversion they can be easily
removed and everything can be simply converted back to standard.

The only mod that some elan owners may have to do is to remove the
fail safe spigot welded to the outer wheel hub axles, they are not required
with a CV conversion.

There are very few elan owners who revert back to donuts after experiencing
the the drive with CV drive shafts... the difference is like chalk and cheese,
and a much more responsive elan.

Ceejay.
ceejay
Fourth Gear
Fourth Gear
 
Posts: 623
Joined: 27 Mar 2007

PostPost by: gearbox » Wed Oct 24, 2012 8:27 am

ceejay wrote:Hi Gearbox
When you say fail, I guess you mean wear out, because with the power that an elan
feeds into the drive line you probably wont ever break any CVs.... but a totally brutal
elan driver may inflict some damage with long term abuse, but my guess is there
are few elan drivers around like that today.

So to answer your question re warranty, if you had a problem within the twelve
month period, we'd oblige with replacement parts, but on past experience which
stretches back more than two decades there has not been any breakages reported
to us.

Id be surprised if a replacement CV set was ever required, the CVs will likely outlast
your elan, but any replacement cost would be based on a per unit CV cost (at the time)
and whatever other costs were involved, I'm not being evasive re cost, just that
it is impossible to predict into the future.


Ceejay.


Hi Ceejay;

Thank you for the quick replies. Yes, I did mean wear out, or used to the point of failure. Good to know that you stand behind your product, not sure why the UK providers are having so many problems with these as they claim to use the same CV. But since we are on this topic, you indicate that your shafts do not bind at full droop, so the machining you do is the trick. But is there any issues with breaking the boot at full droop as Piss-ant describes? This would be very anoying for road side tire changes. But the reason I asked about replacements was mainly that you have a very unique product, and 5 or 10 years from now, should I need a replacement and should you not be around anymore or not making them for what ever reason, I would be out of luck. So if I do purchase your shafts, I would be inclined to buy a spare CV or set just in case to protect my investment. So what would they cost today if I would buy the spare along with a new set of shafts? Thanks again, Allan
gearbox
Third Gear
Third Gear
 
Posts: 396
Joined: 12 Mar 2012

PostPost by: ceejay » Wed Oct 24, 2012 11:04 am

Hi Alan.

GKN CVs will cover 70,000 to 90,000Km before you would even think about
replacement, I reckon the average elan would cover around 4,000 Km per
year on average, that gives a rough life span of 22 years... give or take a
couple.

(Good second-hand, & and I mean "good" GKN CVs can be used, and they will even
last for many years, they are damn tough).


Where will your elan be in 22 years?... I'm sure that I, and perhaps many other current
elan owners wont still have an elan in the garage in 22 years time if you are on the
wrong side of 55 or 60, still I may be wrong there.

As I said previously, I have not had anyone inform me of a boot splitting or breaking
due to any strain on full droop, I'm not saying it wont happen, because as soon I
say that, Murphy?s law will take over.

Yes, a unique product it is, but before I leave this mortal coil I will make sure that
someone else can take on and continue the building process.

To be honest, I think that you would be over spending by ordering another set
of CVs to "put away" as you say, I don't think you really need to do that.
That is the first time someone has mentioned that idea to me.

If you, or anyone else is considering a CV DS purchase soon, (At this time)
we happen to have good stocks of CNC machined and splined half shafts
plus adapter plates, but of course we still have to spend the time building
to order, it usually takes around three weeks from order placement to shipping,
at times it has been much less, but we have found that it is wise allow a bit
of extra time...we don't want to rush things.
Ceejay
www.elantrikbits.com
Live your dream-wear your passion.
http://elantrikbits.com/lotus-elan-blog/
ceejay
Fourth Gear
Fourth Gear
 
Posts: 623
Joined: 27 Mar 2007

PostPost by: ftsoft » Wed Oct 24, 2012 12:26 pm

"I do remember that there was noticeably LESS wind-up surge on the ribbed ones, so they must be quite a bit stiffer."

Aha! I just replaced mine and didn't know if I was just imagining that they were stiffer. The car is noticeably stiffer, but then I'm older and might just be suffering more.

Frank
66 S2 26/5194
LP4711LA-B
User avatar
ftsoft
Second Gear
Second Gear
 
Posts: 181
Joined: 15 Sep 2009

PostPost by: Spyder fan » Wed Oct 24, 2012 6:53 pm

Apparently in the UK and Europe we will all be required to retrofit these old dinosaur parts if the EU get their way.

Extract from Daily Mail, but it's reported elsewhere and everywhere and thankfully appears to be a non starter.

Millions of modified and classic cars could be banned from the roads as meddling European Union try to shake-up MOT rules
'Ridiculous' proposals suggest that cars cannot be modified once they leave the factory
Motoring organisations say most changes do not affect a car's safety and potential rule is completely unnecessary
Changes that are made to make classic cars safer would be illegal
If new rules implemented it could cripple industry and thousands may lose their jobs
http://www.dailymail.co.uk/news/article-2199311/Millions-modified-classic-cars-banned-roads-meddling-European-Union-try-shake-MOT-rules.html
Kindest regards

Alan Thomas
User avatar
Spyder fan
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2843
Joined: 11 Jun 2009

PostPost by: gearbox » Thu Oct 25, 2012 1:58 am

Spyder fan wrote:Apparently in the UK and Europe we will all be required to retrofit these old dinosaur parts if the EU get their way.

Extract from Daily Mail, but it's reported elsewhere and everywhere and thankfully appears to be a non starter.

Millions of modified and classic cars could be banned from the roads as meddling European Union try to shake-up MOT rules
'Ridiculous' proposals suggest that cars cannot be modified once they leave the factory
Motoring organisations say most changes do not affect a car's safety and potential rule is completely unnecessary
Changes that are made to make classic cars safer would be illegal
If new rules implemented it could cripple industry and thousands may lose their jobs
http://www.dailymail.co.uk/news/article-2199311/Millions-modified-classic-cars-banned-roads-meddling-European-Union-try-shake-MOT-rules.html



Hey Alan, Why is it, that in the most dire world economic downturn in 7 decades, our governments on both sides of the Pond feel it necessary to focus it's energies on social issues at the cost of furthering the destruction of our economies? As Thomas Jefferson once said, "People will get the government they deserve". Well I think we can do better. How did we get here in the first place?
gearbox
Third Gear
Third Gear
 
Posts: 396
Joined: 12 Mar 2012

PostPost by: ceejay » Thu Oct 25, 2012 2:57 am

Two words - "Excessive Greed" by a controlling minority!!
Live your dream-wear your passion.
http://elantrikbits.com/lotus-elan-blog/
ceejay
Fourth Gear
Fourth Gear
 
Posts: 623
Joined: 27 Mar 2007

PostPost by: gearbox » Thu Oct 25, 2012 10:19 am

ceejay wrote:Two words - "Excessive Greed" by a controlling minority!!


LOL, are we talking about the Bildenberg Group?
gearbox
Third Gear
Third Gear
 
Posts: 396
Joined: 12 Mar 2012
PreviousNext

Total Online:

Users browsing this forum: No registered users and 18 guests