David.Ashley.Poole

Hello L7Cs, after my car was remapped by the two Steve’s the speedometer stopped working - due, I think, to the vibration on the rolling road (they took it to 160 mph (!)). I pulled all the instruments out to see if anything was disconnected or damaged, but everything looks fine. I also replaced the sensor and set up the clearance.. but is still does not work. I cannot find the 1 kOhm pull-up resistor on the sensor line, and it does not appear to be connected from the VOM readings. Could anyone help me with what the thing looks like (is it just a standard 0.25 W resistor) and where it might be hiding? Or any other suggestions? The tach pull-up is quite obvious but it is a 4W and has its own connector. Hoping you can help - you are my only hope, Obi-Wan....

Hello L7s, I have a CSR 260 and there is a nasty vibration/mechanical sound on overrun in sixth between 70-90 mph. It does not occur in fourth or fifth at the same speed/propshaft rpm. I recently had the gearbox rebuilt by Road and Race and Phil tells me that is caused by propshaft resonance and is a common feature in CSRs. So I was wondering if anyone else had experience of it and if they had any solutions. I have contacted carbon propshaft manufacturers and plan to get one made if no other solution presents itself, with the hope that the lighter propshaft weight will push any resonance higher in frequency, and that the increased damping in carbon fibre will reduce the magnitude. And suggestions welcome, including “buy a new gearbox”...

My CSR 260 propshaft has a resonance period on the overrun around 80-90 or so. I talked to Phil at R&R since I thought that it was my 6 speed... and he said it was the propshaft, and he was right. It does it in any of the top three gears. So I thought that a lightweight carbon propshaft would push the frequency up out of the operational range, and it would have excellent damping qualities too. I saw one on sale on eBay but missed it, and I was wondering if anyone had (i) had one made, (ii) mechanical drawings or specifications that I could use to get one made up or (iii) an old one that I could borrow as a template. Or (iv) any other ideas or comments. The UJs are not loose... but I might change them anyway and see if they made a difference. Perhaps I can find some lightweight UJs.

Hello Jonathon, i have lots of CC documents, but nothing that addresses the dry sump tank that you mentioned. I have the Assembly Manual 1.0 which looks fairly recent, but it does not have a date, so who knows... But on the plus side I found a book called “The Devil Drinks Sangria” by Caterham Valley when I did a Kindle search. So perhaps I should try that before I go any further... LOL.

Hello L7s, i would very much appreciate it if anyone can let me have documentation (or a reference to some) on the Cosworth 260 dry sump and main tank oil system. I have the CC CSR build addendum, and the Cosworth 260 build manual, but neither has anything on the oil system. And I would really (really) like to know what is inside the swirl tower and the bell housing that, I presume, holds that tank...

Hello Kingsley, Thanks. I actually thought that might be the case... but I was also contemplating getting some new CF wings from CC and asking them not to drill the front mounting hole. But, in truth, I am pretty happy with the CR500s. I will ask Avon if they have changed from Kevlar to steel, though.

I have been talking to Avon about CR500s for my CSR. They say that they intend to keep them in production, and that they only have one compound. This is their recent quotation... and they are about to deliver four of them. I am not keen to transition to the ZZS since is not the intended aspect ratio, and they are heavier. But I doubt if I would notice the difference, once I had finished fooling around with the front mudguards so I could get them to fit. And I think that they must intend to keep making them, since tires on the shelf only have a limited life before people will start complaining about the build date, but I will ask about this before I order them. But I bet I wear them out before they time expire... LOL. “We currently have stock available of both sizes requested below. You can purchase them direct from us and the tyres can be despatched for a next working day delivery if ordered and paid for before 12 o'clock. The CR500 are only available in the one standard compound. Here are the prices again... 195/45R15 CR500 - £129.50 + VAT 245/40R15 CR500 - £166.30 + VAT Freight - Approx. £20 + VAT (per set)”

Hello, i was was wondering if anyone has a mechanical drawing of the CSR 260 silencer? I am planning to get a new one from BTB exhausts, and they want a drawing or the original in person, so to speak. I can make one if nothing exists, but I would rather not since I have to learn a new CAD program before I start... probably good for me though. LOL

Hello Mark, i have a lot of (unwanted) experience in tracking lost cables... In the US I have a 2002 Morgan Plus 8 and there is absolutely no documentation on the car from MMC. Mind you, it is beautifully built in a hand-constructed sort of way. LOL. So I use a cable tracer that I bought from Home Depot, the US equivalent of B&Q. It generates an RF output modulated with an audio warble, and you use alligator clips to attach the output to the cable in question and ground, and then use a proximity tracer wand to find the route and other end of the cable. I find it quite invaluable, for everything from failure resolution to ECU sensor analysis to what fuse does what investigations. In the U.K. I have a CSR, and there are a couple of unused cables emerging from the loom at the engine bulkhead that I want to trace. There are lots of these tracers on Amazon UK from about 20 UKS up - and I will buy one next Spring when I return, but I do not have any recommendations yet. It sounds to me as though the previous owner of your car could (or did) not fix the problem and added the dashboard switch as a solution... but it seems possible that the thermostatic switch may not even be connected. So I would start with a signal trace at the dash switch, then follow up from the fan, and finally the thermostatic switch, and see what is connected to what. And then, as the song goes, you will be able to say “I can see clearly now...”(!). Let us know if you buy one and how you get on.

Hello Mark, i have a lot of (unwanted) experience in tracking lost cables... In the US I have a 2002 Morgan Plus 8 and there is absolutely no documentation on the car from MMC. Mind you, it is beautifully built in a hand-constructed sort of way. LOL. So I use a cable tracer that I bought from Home Depot, the US equivalent of B&Q. It generates an RF output modulated with an audio warble, and you use alligator clips to attach the output to the cable in question and ground, and then use a proximity tracer wand to find the route and other end of the cable. I find it quite invaluable, for everything from failure resolution to ECU sensor analysis to what fuse does what investigations. In the U.K. I have a CSR, and there are a couple of unused cables emerging from the loom at the engine bulkhead that I want to trace. There are lots of these tracers on Amazon UK from about 20 UKS up - and I will buy one next Spring when I return, but I do not have any recommendations yet. It sounds to me as though the previous owner of your car could (or did) not fix the problem and added the dashboard switch as a solution... but it seems possible that the thermostatic switch may not even be connected. So I would start with a signal trace at the dash switch, then follow up from the fan, and finally the thermostatic switch, and see what is connected to what. And then, as the song goes, you will be able to say “I can see clearly now...”(!). Let us know if you buy one and how you get on.

Hello Pete, Thanks for the info on DRLs. I read the relevant regulations, and although they seem to be a hit vague they are also clear that the DRLs should not dazzle anyone at night. So my plan was to power them from a single-pole double throw relay, energized by the sidelight voltage, with one throw connected to the ignition bus and the other to the main beam headlight bus. This would mean that the DRLs would go on with the ignition, and go off when the sidelight were on - except when the main beams were on, when they would act as additional main beam lighting. Any comments about the legality of all this would be welcome....

Hello David, Thanks for your kind comments. Actually, I was not totally sold on the color until I saw the CSR. And then, as you may have read, it was love at first sight. LOL. I was reading your blog, and I have to say that in my experience spray cans work just as well as any other paint, as long as you do the prep properly. The great thing about them is that the quality is really under your control,- and you can do small areas instead of the whole car when things get complicated – and expensive. I would have been very happy with 153 bhp in any of my sixes and sevens – that was pretty good for an early BDA – and would have seemed quite electrifying to me at the time. We have become a little more jaded since… I actually live in the USA, and only have a holiday home with a tiny garage in the UK through Unplanned Events. But I really like being back – I was a teenager in Weymouth before I joined the Royal Navy and finally wound up in the America. I have a 2002 Morgan Plus 8 here as my daily driver, and I have changed the engine and just about everything else. It came with a really wimpy and somewhat obnoxious 4.0 Aluminium V8, but I changed it to a Stage III 4.5 that makes only a little more power than my CSR (!). And the combination of working from home in Weymouth, meetings with the company in London, wind and kite surfing at Portland (something of a work in progress, I must admit), running on the beach and driving my CSR has me captivated. Here in the USA they have the Constitution, which has Amendments. The Fifth amendment means you can refuse to reply if the answer will incriminate or embarrass you. So I believe that all Morgan and CSR related expenses are protected by the Fifth. Just saying... Good hearing from you. And do you have a picture of your car? Here is my Morgan… but it is almost the complete opposite of a Caterham in engineering. All the best, David Poole

Hello Jim, i am not sure (yet) what my map looks like, or if it has ever been updated. I wrote to SBD to see if they could shed some light on what might be possible, and to buy an interface, but they have not replied so I will have to give them a call. The ECU is a closed book to me at the moment, but I intend to get to grips with it in the Spring. The kangaroo-ing was not bad after I replaced the Lambda sensor, but the Iridium Plugs made the final difference. I also indexed them when I fitted them. It is not as easy indexing conical seated plugs as the flat washer variety, but I did it by buying 16 (!) and swapping them around until I got all the electrodes pointed in (more or less) the right direction. I assume that I will need lots since the manual says that they should be replaced every 3000 miles, but this seems to be a bit OTT. But if you have any insight into the ECU and engine I would be very glad to hear it. It may be interesting that I wanted to buy a 620S, but I could not find one for sale anywhere in the Spring last year. I only use my car on the road (it is actually my only car, since my wife is – sensibly - unenthusiastic about me driving her car), and the CSR is probably better suited to that than a 620 would be... but I do admire them. i plan to pull the engine and gearbox out (or get Chapman to pull it out - I do not have a garage large enough to do it myself) in the Spring since the gearbox, although it changes nicely and the synchros are good, has a worrying attribute in that the gear lever moves forward and back slightly during power on/off transitions. And I am sure that this means that the main shaft has picked up some endplay, which, together with the whine in third and fourth, is not conducive to peace of mind. I talked to Philip at R&R at some length about this, and I have it booked in for April. He said that fourth whines because of the gear design, which CC decided not to change for cost reasons. He also said that the lightweight countershaft from Tracsport is not really worthwhile, and that he would replace the shifters if there were not of the latest standard. No doubt this will all become clear in time… but comments are welcome. I am also unsure about getting the engine sharpened up while it is out. It only has 21k miles, but it is 10 years or so old. So some advice on new bearing shells, rings, valves, oil seals etc. and whether they are worthwhile would be appreciated. All the best, David Poole. I

Hello Paul, What a man!!! And on the dining room table! I have never seen such bravery... LOL. But I think that after you get the paint off your bigger problem is going to be getting a consistent finish over the remaining bare Aluminium. I have only tackled stainless sheet, and I had great results with the same random orbital polisher that I use on my paint. It is very safe and benign, and produces a completely swirl-free pattern that I have never managed to achieve by hand. I would not - or could not - use a rotary polisher on the inside of a bonnet since they are jolly difficult to control. I was once polishing a brass bonnet hinge on a rotary polisher outside my garage, when it seized it in a total frenzy and threw it several hundred maters into the woods. Never found it again...

Life with a CSR – 2 I did not realize that my table of gear ratio/speed calculations was going to become so Horlicksed up when I posted them, so here is another shot. If anyone would like the spreadsheet just shout… the blue cells are inputs and can be changed to suit various ratios. And I forgot to mention the headlamp re-location. CC have new, lower, headlamp mounts for the CSR that fit onto the top front wishbone mounting, and I decided to fit these. Here is the before shot… This made me build new headlamp sub-looms, since the cable routing is entirely different (it has to go from the rear of the front wishbone, along the space frame diagonal bars at the top, to the front of the wishbone). So I ordered the correct color-coded wires, six-way Encoseal connectors, pins, seals and a crimping tool. I made the sub-harnesses 1.5 meters long, and left the headlamp-ends clean so I could thread them through the mounts and headlamp bases. The Econseal connectors and crimping tool I found a definite challenge – fortunately I had ordered about twice as many pins as I needed – and getting the core cable, seal and insulation (the seal is crimped with the insulation) all correctly crimped was a definite challenge. I should have made a U-Tube video – how not to crimp Econseal connector pins… LOL. And while I was at it I replaced the front indicators, rear lamps, rear fog and reversing lamps since they were all rusty to some degree. And I finished off with LED bulbs all round and a new digital indicator flasher unit. This left the original tubular headlamp mount clamps free, so I am making up some Daytime Running Lights mounts as a trial. I bought motorcycle DRLs and plan to wire them so that they are permanently on with the engine running (there is an ignition bus running down the chassis next to the lights that is not presently used), but use a relay to turn them off with when the sidelights are on, and back on again when the main beams are on. So we shall see… or not. The LED headlamps came with the car and I have not used it enough at night to really form an opinion. It gets dark so late in summer that it was difficult to evaluate them properly, but the dip cutoff was very sharp indeed and they were very white. I have not been able to track the make down yet… And while I am collecting sundry missing thoughts, here is a photo of the primaries with the insulation tape. I have used Thermotec wrap in the past - it starts out looking fairly smart but gets ratty in a hurry, and steams so much in the wet, even if you use their spray, that it quite alarms pedestrians. I bought the wrap from DT – made by Design Engineering – and it seems excellent so far. But I realize that I should have wrapped the primaries from the collector end back to the manifold stubs, so that the outer ends were neater, instead of the other way round. The last time I wrapped primaries they were a four into one integrated design, and wrapping them in the direction of flow was the only option. Ah well, next time… I had considered getting them Zircotec coated but I thought that two weeks without the car seemed a long time. In the event the builders parked a skiff in the drive for a few days that turned into nearly a month, and I was marooned the whole time. Hindsight is a wonderful thing. I was also not sure to do about the exhaust finish – polishing did not seem quite the thing, so I was trying to get them media blasted with walnut shells to get a satin finish. The only local source used Aluminium Oxide and then glass beads, so I went with that option. It came out looking jolly nice however, in an industrial sort of way, and it was sympathetic to the rest of the car. But I will probably replace the silencer in the Spring with a Raceco, since it is presently a bit noisy. And since my last post I have decided to replace the seats with a pair of GT from Thunder Sports. The present seats are not – puzzlingly – a pair, and although they look very similar the passenger seat is clearly the newer and has a back that is about 20mm taller. So I think that CC must have changed the design - probably around 2008 – and if anyone has more information I would be interested.

Hello L7Cers, My name is David Poole and I am the new owner of a 2005 CSR 260. Well, six months owner. Recently my thoughts kept drifting back to the Lotus 6 (1498 Laystall-Ford) that I owned when I joined the RN. It had a hood, but no side-screens or heater, and I loved it dearly. I drove it from the Britannia Royal Naval College, with my kit stuffed into the passenger seat, to my next posting, where I crashed it. But I had another Lotus 6 (1466 XPEG Laystall-MG) some years later, and then a Seven (1500 Crossflow) – all road cars. I live in Weymouth, work from home and in London, so it was not much of a stretch to get the train to Caterham at Gatwick. They had a lot of nice cars, and let me drive a somewhat ratty 420R demonstrator. But I was not totally sold, and so I arranged a drive in a new 420R and new-ish 420S at Williams in Bristol. Now this was interesting, since the 420R had a six speed gearbox. But although I liked the R – and the six-speed - quite a lot (but did not like the S much) somehow I was still not bonded to either car. And then I saw that Chapman Cars in Kent had a 2005 CSR for sale. Now I have always thought that the CSR was the pinnacle of Caterham engineering, and had been looking for one for some time. How CC managed to produce such a sophisticated car was a mystery to me, and why they stopped making if after a few years was an equal mystery. But I could not resist… so I put down a deposit, arranged the train tickets, was collected at the station by Anthony Paine, and had a test drive. In the rain… and that, as they say, was that. And this blog is an attempt to document my progress, and also solicit advice from you chaps who are clearly more experienced with these cars than I. And this is it… a 2005 CSR 260. Many owners, 20,000 Miles, built as a knockdown CSR 200 (kit) car, converted to a 260 by Caterham in 2007 with a 260 engine and six speed gearbox, and a Quaife ATB in 2008 when it had its first MOT. It has a very comprehensive service history and is in wonderful – almost like new - condition, but although the paint was great it was jolly dirty in the cockpit despite Chapman’s best efforts. When I test drove it the diff whined a bit, but it was nothing to complain about. After the high speed run down the M3 to Weymouth it was a different story, and it was howling like a banshee and had a lot of freeplay by the time I arrived. I initially thought that this was going to be a case of caveat emptor, since I could not imagine anyone being sympathetic to a Caterham owner complaining about a noisy diff (!). I was considering pulling it out and getting it rebuilt myself, but I thought that some advice from Anthony and Damien at Chapman would be useful… and the response was quite outstanding. They insisted that I brought the car back to them and let them have it rebuilt by Road and Race – and I then called Philip at R&R and after a chat he found a 3.14 CWP that he had in stock and he fitted that, new bearings and seals, and rebuilt it. He said that many of the original 3.48s had been manufactured by Hewland for racing and they were not too concerned about noise. It also had no preload…. But the rebuilt unit is totally quiet, the freeplay has gone, the ratio is ideal, and you can only hear a whisper from the ATB on corners when you have the sidescreens off. Philip clearly knows what he is doing. I put this table together in Excel to see what the ratios look like in practice – and this is with the standard CR500 245/40R15 rear tires at 896 revolutions/mile. Max power is at 7500 and max rpm is 7800, and you can see what a beautiful set of ratios these are for this car. Speed in gears RPM Final Tyre R/Mile 1 2 3 4 5 6 1000 3.14 896 8 11 13 16 19 21 2000 16 21 27 32 38 43 3000 24 32 40 48 57 64 4000 32 42 54 65 75 85 5000 40 53 67 81 94 107 6000 48 64 80 97 113 128 7000 55 74 94 113 132 149 7500 59 80 101 121 142 160 7800 62 83 105 126 147 166 Ratios 2.69 2.01 1.59 1.32 1.13 1.00 Percentage change -34 -26 -20 -17 -13 Next gear RPM at 7500 change 5604 5933 6226 6420 6637 Next gear RPM at 7800 change 5828 6170 6475 6677 6903 Sine then I have rebuilt the front suspension – I thought one of the Heim joints was rattling, but after I replaced them all it turned out to be the lower steering column hitting one of the exhaust primaries. But I did discover that one of the steering rack gaiters was torn and the rack slightly rusted, so I replaced it with the high ratio “race” rack, which turned out to be the same 2.0 turns lock to lock as the original. I thought it was going to be around 1.6, but a chat with Darren at CC parts cleared up that misapprehension. I also replaced the lower column, which was getting a bit ratty, and had not realized that the lower column sets the end-play in the upper column, which was grinding against the horn button slip ring. So this turned out to be the proverbial “n birds with one stone” deal. At the same time I swapped the original Momo 300 mm Team steering wheel for a 320 mm Jet, since the 300 mm wheel made the indicator and light stalks (I have the integrated cockpit) stick out like Ross Perot’s ears. As they say… And over the summer – when I was grounded since the builders were in – I pulled the exhaust off and had it media (Aluminium oxide and the glass bead) blasted, and insulated the primaries with titanium wrap; replaced the windscreen, which had some dings; fitted a set of weather equipment from Thundersports (the car had never had any); and compounded and polished it with my random orbital polisher. And then I tackled the on/off throttle transition problem that had plagued me – more or less – since I bought the car. It was always easy to promote a kangaroo hiccup if I was not extremely smooth in applying throttle, and I managed to compensate somewhat by pressing my foot against the side of the cockpit. In the past I had improved idle quality by changing to Iridium plugs, so I decided to try them in my CSR. And the results were pretty amusing – they irritated the car immensely, and it became almost undriveable. So I swapped them back to the originals and thought about it for a couple of days. Now the plugs were pretty black, but Damien said that the Cosworth engines typically run rich. But there is rich and rich, and I came to the conclusion that the ECU was running open loop and that probably the Lamba sensor was not – well – sensing. So I replaced it with a Bosch equivalent, and after 100 miles or so I presumed that the trim maps had been updated and the engine settled down to a very civilized behavior. So I put in the Iridium (TR7IX) plugs again, and it became even better, and now the transition problems have gone and it is a delight to drive. Next year I plan to refinish the wheels since they are losing the paint on the inner tears 9but I am not sure about the color – originall or body colour, that is the Question), and replace the tires. I think I will stick to CR500s since they were designed for the car and I am not enthusiastic about modifying the front mudguards to take the larger section ZZS. And I am going to get the gearbox rebuilt when I investigate the rattle in reverse, which I think is the clutch. And that is about it, apart from bonnet stripes and a shift light – but I am unsure about the seats, which are not (quite) a pair, and I have been thinking about the Thundersports GT seats and would welcome comments on the choice. So my conclusions? Chapman cars are a truly excellent company, and I have no hesitation in recommending them without hesitation. And the CSR? Pure magic. Great ride, wonderful feedback, more power than you (usually) need, best engine and gearbox ever, outstanding brakes and roadholding. I am bonded.

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