stevefoster Posted April 24, 2003 Share Posted April 24, 2003 I agree with you Nigel. I wouldn't expect a new tube either but I do want to know if I am at risk. I called Len. I am going for Ali bodied dampers that bolt throught the proper place and have the spring poundage I want. Almost the whole body of the damper is threaded and so can cater for the adjustment I need. Form an orderly queue behind me as I need them soon for the next race meeting. Oh, I hope to be infront of Rob next time incase his tube fails! My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Edited by - stevefoster on 24 Apr 2003 16:50:55 Link to comment Share on other sites More sharing options...
rgrigsby Posted April 24, 2003 Share Posted April 24, 2003 Hmmm interesting, I think I've got the "short" dampers as they bolt through the Dedion tube not through a bracket mounted on it. In terms of use since I've had V7SLR's DeDion tube the car as done 25+ track days around 7K road miles and the Targa Liege, including LOTS of kerb hopping on tracks with slicks and generally being driven very hard. It was all fine when I had a look at during the rebuild in Feb. Whether that means the shorter dampers are better I don't know. I guess now I'm putting more power with wider (9") slicks through it I need to keep an eye on it. Here's a pic of the tube on my car, the damper bolt goes through the hole you can just see on the back of the tube. Is that the "short" damper mounting point? I could be wrong but looking at that picture I can't see the other damper mounting point at all???? Steve does that mean you're getting AVO's? that's not fair, time for me to get a set of Nitrons 😬, where's that credit card gone!! Cheers Rob G Edited by - rgrigsby on 24 Apr 2003 16:54:46 Link to comment Share on other sites More sharing options...
stevefoster Posted April 24, 2003 Share Posted April 24, 2003 Blimey Rob. I need a wash should be fingered on the car somewhere Was that photo taken after a rally? Yes Avo's on the rear at least and the ali ones cos there bound to be faster... Another worry. Does the weld cause the tube to be weak even if the use the higher point? Or am I being paraniod ... Paranoid. I'll go and lie down... My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Edited by - stevefoster on 24 Apr 2003 17:04:38 Link to comment Share on other sites More sharing options...
rgrigsby Posted April 24, 2003 Share Posted April 24, 2003 Sort of... I didn't bother cleaning it as shortly after that the bodywork was replaced !! then it got a proper clean 😬 Ahh AVO's on the rear, in time for Lydden next weekend? I've still got the original 1992 Bilsteins so I probably should replace them with something a bit more recent at some point!! Rob G www.SpeedySeven.com Edited by - rgrigsby on 24 Apr 2003 17:08:32 Link to comment Share on other sites More sharing options...
stevefoster Posted April 24, 2003 Share Posted April 24, 2003 They seemed to work fine to me Rob... My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Link to comment Share on other sites More sharing options...
V7 SLR Posted April 24, 2003 Share Posted April 24, 2003 From the explanation of what's new (thanks Dave), I deduce the following: a) Mine must be of the older type because the SV wasn't around when I had my new de Dion. b) Can't comment. No idea. c) No idea. d) I guess this means if you have a hole for the upper mounting, then you have the older type. This means I reckon that if you buy shorter dampers to suit that hole, and you subsequently wipe out your de Dion, then you might not be able to get a replacement de Dion to fit your new dampers. Think about this. Have I got the right end of the stick? e) How does an increase in width help with clearance of calipers as they are bolted to the end of the de Dion anyway? f) I'm pleased about this. I always thought rear toe-in was odd. ISTR mine being parallel anyway proving their manufacturing tolerances couldn't be that exact. I always intended to have it checked on a laser system but never got around to it. Rob, get your car washed. I couldn't tell from your picture where your damper bolts through... especially because your damper appears to be missing in that piccy... oh hang on, I think I can see the bush in the middle of the de Dion. You do have the tacked-on bush too don't you? You must have (I guess) because that must have been the one I was using. Right, who's coming to Ireland in May? I think some car park comparisons are in order. Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
Peter Duce Posted April 24, 2003 Share Posted April 24, 2003 Dave, I had one go a couple of years ago on a 1997 car. Approached Caterham and after some hassle they fitted it for me at half price. The mounting on the new one is definitely different. I have a pic, but it looks similar to yours. I found then very helpful ....eventually. Hope this helps. Peter Link to comment Share on other sites More sharing options...
stevefoster Posted April 24, 2003 Share Posted April 24, 2003 Ok Nigel, Didn't think about that one. Yes one might be in trouble if you stuff the old tube. either 2nd hand or get it repaired or have a one of made by someone. I understand that some rear toe in is a good thing. Without it the car will be unstable esp under braking / trail braking. My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Link to comment Share on other sites More sharing options...
Chelspeed Posted April 24, 2003 Share Posted April 24, 2003 According to Caterham the installation concern that they allege is causing the failure is allowing the damper bolt to work loose. Presumably running with a loose lower shocker bolt means the force from the damper on the mount is amplified as it is acting thro the the longer half undone bolt as a lever. So if you have the shocks mounting on the lower mount make sure they are tight. Ironic that the list of differences on the new tube says the original mounts have been deleted to increase tube integrity when it's the new mounts that have led to failure. It also fails to mention how much extra it weighs..... Not a concern to those in a one make championship but of interest to me. I wonder how long, if at all, they will continue to sell the old tube? I don't want to change to the new design as I have no more room under the arches for wider track, I run the dampers in the original middle mounts and I don't want the extra weight. Will be under the car tomorrow with the dye-pen kit. Link to comment Share on other sites More sharing options...
Jason Plato Posted April 25, 2003 Share Posted April 25, 2003 I would expect Caterham are reading this - are we to recieve a response please ? dave Link to comment Share on other sites More sharing options...
Mike Bees Posted April 25, 2003 Share Posted April 25, 2003 FWIW the change from through-bolting the damper to the tacked-on-underneath mounting point was part of the 1997 package of suspension changes. I assumed that it was geometry-related. Mike Link to comment Share on other sites More sharing options...
Dave_H Posted April 25, 2003 Author Share Posted April 25, 2003 And if there was no problem with the “old” design shock mount like mine, why is there a big **** off gusset on the new ones… 🤔 Dave Link to comment Share on other sites More sharing options...
stevefoster Posted April 25, 2003 Share Posted April 25, 2003 I think they wanted to run longer progressive spring and needed a longer damper. To make it fit they tacked the lugs on lower down. Interesting about the 0 toe. Agreed to reduce rolling resistance... Dave have you got your ears shimmed like this for the 1/4 milers... could make a bit of difference. I could just buy a new tube and keep the dampers I have for future proofing / keeping the car Caterham spec'd original then... My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Edited by - stevefoster on 25 Apr 2003 09:45:17 Link to comment Share on other sites More sharing options...
Steve-B Posted April 25, 2003 Share Posted April 25, 2003 so if i read the bulletin, our May 2002 SV has the uprated DD on it. i guesses i read it from looking at the tube, and seeing if it has a seam or not eh 🤔 Steve 210Bhp Sinister Version-VHPD here Link to comment Share on other sites More sharing options...
Graham Perry Posted April 25, 2003 Share Posted April 25, 2003 Even if they do stop making the old one, it woudn't be difficult to get one made by a competant engineering co. When I had the cracks repaired in mine (early version). The guy that did the welding was not complimentary about the original welding. He had a lifetimes experience behind him and reckoned the cracks mine had had been there since the day it was welded from new as they looked like they were caused through heat contraction when the original weld cooled Link to comment Share on other sites More sharing options...
stevefoster Posted April 25, 2003 Share Posted April 25, 2003 Right. I'm going Freestyle ali then. My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Link to comment Share on other sites More sharing options...
Caterham Aftersales Posted April 25, 2003 Share Posted April 25, 2003 Dear All, I was contacted by Steve Foster on behalf of you all, advising me that we (Caterham) should take a look at this thread, which I duly did and replied to Steve. Having had another look at the thread today, I'm sure the reply would be of interest to you all - so I have decided to post it here as well: Dear Steve, Thank you for your email - I have read the comments on the thread you directed me to with interest. It saddens me to think that the members of the forum feel that Caterham have no interest in owners problems. In the recent past we have recalled significant numbers of cars for *potential* problems eg: driveshafts, rear hubs etc. We could have dealt with the cases that have arisen individually, but chose to act in the interest of our customer base and offer free of charge replacements for everyone potentially affected. You will probably have seen that I have used Blatchat as a medium for this, most recently the 'R' clip on the brake pedal. De-dion tube failures are rare. We have investigated those that have been presented to us and found the common factor to be the damper being loose (ie 'an installation issue') Moreover, we inspect the tube as part of regular servicing and would be aware of any further problems. Compared to the isolated few, many thousands more are working completely satisfactorily. It is a shame that any improvement we make in the product is seen as an admission that the previous part was not suitable. In reality, suppliers, production techniques, legislation and applications change, and where possible we use these changes to make our product faster, lighter and stronger. This is, and continues to be, the case with the de-dion tube so it is likely that it will be revised at some point in the future for these reasons. The recent improvements to the tube have been carried down from R400 race series development. The tube was made wider to accomodate a new slick (which has more deflection and would have fouled the watts link). More width means more stress, so the specification of the material was increased to match the SV tube. Finally, the redundant bush was removed to improve integrity, reduce weight, reduce confusion, and remove some cost. None of these improvements have been as a result of failures. The latest tube actually costs us more to produce, yet we have not increased the retail price. Whilst Blatchat is an excellent forum for the exchange of information and social contact, it should be remembered that the messages posted are the views of the member and may not contain adequate or accurate information for a balanced judgement to be made by the reader. For example, having read this thread I made a swift scan of others and found statements by well known club members that are simply wrong (ie. re EU3 on roller barrels and the Supersport-R). Unfortunately, we do not have the resource to have an active presence on Blatchat, but we are here to answer any questions you may have. I hope this information has been of interest to you and I would not hesitate to reassure you that a properly maintained car is going to remain safe, durable and a lot of fun. Best Regards SIMON LAMBERT Aftersales Manager Link to comment Share on other sites More sharing options...
V7 SLR Posted April 25, 2003 Share Posted April 25, 2003 It saddens me to think that the members of the forum feel that Caterham have no interest in owners problems. I don't think that's true. The original post explains how Caterham weren't interested and blamed the installation without explain what exactly was wrong with the installation. Very much later in the thread we finally find out what Caterham had objected to in the installation. Now that it is explained, I'll happily accept that.Compared to the isolated few, many thousands more are working completely satisfactorily.I agree with Simon about this, hence my originally trying to determine whether it was a manufacturing fault or design fault. Caterham appear to have determined that it is neither, favouring "installation" issues. OK. I accept that but it is a shame that a warning has not been posted about how loose dampers can break the tube.The tube was made wider to accomodate a new slick (which has more deflection and would have fouled the watts link).OK, thanks. That's helpful. In fact that's very helpful. I've noticed my wide rear ACB10's have scuffed the powder coating off the watts linkage. I've actually ordered some custom-made wheels recently with a shade more offset, but I would guess that the wider de Dion will have the same effect. One last thing, will the old type be continued to be made? Just thinking that some people may have to replace not only a de Dion following a crash but a set of rear dampers too. Seems a shame but if that's progress then I suppose it's good. Worcs L7 club joint AO.//Membership No. 4379//Azure Blue SLR No. 0077//Se7ens List Tours Link to comment Share on other sites More sharing options...
Ted_7 Posted April 25, 2003 Share Posted April 25, 2003 I remember this adventure, almost 2 years ago here The answer to that problem was : Alain, Thank you for your email which has been passed to me for reply. As you are aware, the car is well out of its warranty period. Therefore, we cannot provide you with a warranty replacement. However, problems such as this are always of interest to Caterham Cars - a new tube may be purchased through our parts department and if you are able to return the broken tube, along with the fragement, we will investigate the matter. Depending on our findings, we may make a contribution to the cost of the new tube. I hope this information is of interest to you and should you have any queries please do not hesitate to contact me. Regards SIMON LAMBERT Aftersales Manager The only thing I've noticed, is that everything that brakes on my Caterham is "normal" (but every problems are well known). Se7enly, Ted_7 Link to comment Share on other sites More sharing options...
stevefoster Posted April 25, 2003 Share Posted April 25, 2003 Can't see if the damper is loose on that last pic. Doesn't look it. Moreover 60lbft and threadlock should keep it in place but regular checks are essential, agreed about that. Thanks Simon for the info. It clears some issues that Nigel covered above. The question he raised about the continuation of old style damper mounting tubes is very relevant (no problem making them lighter, stronger, faster of course). I read once the aim is to assist all series of Lotus and Caterham 7's to be kept on the road by service parts. This would be possible with a new tube and damper I guess but is a bit expensive should only the tube need replacing for some reason. I think we have a duty to involve Caterham on threads where it is necessary so that they can put the car makers pov across. My racing pics, 7 DIY, race prep. Updated often here Photo's of the year here Hants (North) and Berkshire Area club site here Edited by - stevefoster on 25 Apr 2003 16:49:57 Link to comment Share on other sites More sharing options...
jerrypike Posted April 25, 2003 Share Posted April 25, 2003 interesting thread have just changed to nitrons on my slr reg jan 2000. these mounted through the middle mount rather than the lower for the original bilsteins. was a slight hassle as i didn't have the longer nuts and bolts, but after reading this may be worth it. will be sure to check the nuts when i swap wheels tomorrow anyone else srinting at longcross sunday? jerry Link to comment Share on other sites More sharing options...
don_g Posted April 25, 2003 Share Posted April 25, 2003 I've been involved with three failures - mine went at Brands GP; luckily with no real problems - I had around half a lap of unusual handling to warn me, but the results of a DD (steady, lads!) failure at speed are too horrifying to contemplate. Surprised to learn of a comparitively 'recent' failure as most appear to be on the older (pre '93?) thin-wall tubing. Those I have seen have failed at the weld on the RHS (off-side) of the 'A' frame mount and seem to be a classic weld failure. I'd rather hoped that the newer, thick wall, tubing had solved the problem - sad to hear that this is not the case. Treat the DD tube as a consumable and change it every ?years. The racers do! (and it's a quick and simple job to change - I only lost one session changing mine!) Link to comment Share on other sites More sharing options...
Peter Carmichael Posted April 26, 2003 Share Posted April 26, 2003 There are two different modes of failure. The post '96 with the wide triangular reinforcement don't fail like yours, Don. They fail with the damper mounts ripping off. The failure that you suffered can come about because of jacking the car up at the a-frame/DD mounting point. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted April 26, 2003 Share Posted April 26, 2003 There are two different modes of failure. The post '96 with the wide triangular reinforcement don't fail like yours, Don. They fail with the damper mounts ripping off. The failure that you suffered can come about because of jacking the car up at the a-frame/DD mounting point. Link to comment Share on other sites More sharing options...
EFA Posted April 26, 2003 Share Posted April 26, 2003 Peter, It was actually the '94 spec didion tube which had the wider triangulation - this was added at much the same time that the tubes went from 18 to 14 gauge steel (if I remember correctly). The problem people are getting here is down to the design of the tube and the lower damper mounting. I guess the longer dampers are used to provide the dual progressive setuip in the '96 onward cars. The older type of mounting (hole through the didion tube) is very strong. I am using a rose jointed dampers on the rear for 15,000 miles with no problem. One thing concerns me with the "if the bolt loosens" theory - The lower damper is secured with a nyloc. Why should this work loose, and therefore is the tube failure a consequential failure of a bad nyloc? I have never seen the bolts work loose, and I have pulled quite a few dirfferent cars apart in my time! Fat Arn Visit the K2 RUM website See the Lotus Seven Club 4 Counties Area Website here Link to comment Share on other sites More sharing options...
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