Purplemeanie

Can someone tell me what sort of rear suspension travel I can expect on a Seven? Assume the car is set to a "normal' ride height and on standard factory springs/dampers (assume adjustable Bilsteins, but not the newest ones fitted to the 420 Cup). The car is an SV if makes any difference. I'm asking so I can work out how high the de-dion tube will travel under full suspension compression. I guess another way of asking the question is - if you assume the rear suspension bottom's out when the de-dion tube hits the chassis tube-work, how high can the de-dion travel above that lower point? And what's the practical limit, as I assume most cars are sprung stiffly enough that they never reach the theoretical maximum compression (or is that assumption wrong?). Thanks, John

Hi Olly, as you've probably seen in Lowflying we're reviewing the Club's website with the view to having the current site replaced towards the back end of the year. We'll add your suggestion to the list of things being considered. John

Hi Green Beastie, That was my website you linked to and I hope it was helpful. There's also a set of easier to digest articles in LF from June/July of 2020. To your point about stock ECU's being locked - they are locked in the sense that the internal maps cannot be updated, they are write-locked. But, I understand there are some people that can get around that. If you think I got anything wrong in LF or on my blog then please let me know by PM and I'll take a look. In any case the information that can be read from the ECU over the OBD port is quite limited and won't show you faults with dials etc., unless Caterham have changed things since my car was built in 2017 :-). Like others on this thread have said, it sounds like the OS rear speed sensor needs some adjustment to sort the flickering speedo (I did mine again only a few weeks ago because I was getting flickers again). I can't offer any suggestions for the rev counter - but on my car the rev counter is not connected to the CANBUS and so not visible on the OBD port (the Sigma engines have CANBUS tacho's but as far as I can tell that's not the case on the Duratec's - though I'm going to check that again now I've done a lot more on Caterham electrics since I wrote those articles). I'm not saying anything different to those who posted above, but wanted to let you know you can contact me if you have any questions about my site or articles. John

SOLVED: So, Colin, I missed the crucial part of your post the first time I read it. You have all 7 slots filled in your relay/module setup. The schematic in the owners manual says that 6 relays are fitted and shows the middle slot empty (of the seven). I fixed it by putting the 3-pin indicator/flasher module into the middle slot (as you said) and putting remaining relays into the other slots (I only have 5 relays as there's no heater fitted and so no heater relay needed). Indicators and hazards now work - phew! Just need to fix the lights, reversing light, fog light and washers now! Thanks for all your help and apologies for a bit of a wild goose chase. TLDR: The relay, marked "indicator relay" in position 3 of the schematic, is a normally closed relay. The exact need for this is still something I'm looking into and I'll hopefully create a schematic of it all over the next few weeks. The indicator/flasher module (not a relay) is the middle module (position 4) in the row of seven. The relay module is what times the on/off switching of the indicators.

Thanks Rob I've PM'ed you. Colin, my car only had 3 relays fitted when I got it. The indicator "module" isn't really a relay so you can't switch that around. But i did try fitting relays to the other empty positions and it just blew the indicator fuse when I tried to use the indicators. Both indicators and hazards are not working. Jonathan, when I get it sorted I'll do a writeup. I've also had someone check their cars (he has 5 Caterhams from various eras) and all them have a 3 pin indicator module. So... my car almost certainly should also have a 3 pin module, I just need to figure out where it goes and what other relays I need to fit to get them working. John

Hi all, anyone know what indicator relay I need for a 2012 Supersport Sigma? The only ones I can see on the Caterham parts site are the short relay or the LED relay (it won't be the latter obvs.). I've tried the short relay from my 420 but that didn't work. From testing with a multi-meter, and looking at a wiring diagram from that era, it looks as though I need a four pin rather than three pin relay? PS: I got the car with no indicator relay installed, so no idea what should go in there. The relays and fuse box is the style where all the relays are in a single line rather than in two rows of three. Thanks, John

Well... I bought a project car! I've bought a 2013 ex-drift car to start this EV project off with and it arrived today. It's in a pretty poor state but is ideal for my needs. There's more about it at the back of this month's LF and lots more to come in the future.

I've been driving an ID3 for 2 years now. It's fantastic around town and gives a different perspective to driving long distances. i.e. we have to plan our journeys a bit better. Having said that we find that our range is limited by our bladders these days and so a stop every couple of hours is fine on a long journey. The instant access to power is intoxicating (even put along side my 420) and is great at hitting gaps in traffic when you're pulling out around town. We also find having an EV is like having a Caterham - wherever to park it you end up in a conversation with someone, especially at charging sites. I can also say that the charging network is much better now than it was even two years ago. There are still the problems of charging if you don't have your own charging point at home - especially for people with no off street parking. But the new super-hubs that are going into the motorway service stations are pretty impressive for the longer journeys. And we're seeing those going into petrol forecourts around here too (Bristol). Charging can still be a pit patchy when you're in Scotland or Cornwall (in our recent experience) though things change very quickly and the situation in Cornwall seems to be improving. Back to Michael's original post though. I firmly believe that electric will be out performing petrol cars on hill climbs very soon. Surely and electric Caterham will outperform a Tesla given it's lower weight and better power to weight ratio. Oh... and watch out for more news from me at the back of Lowflying this month and on Blatchat in the next few days. Very exciting!!!!!... well it is for me at least! John

Need to recover some project sized space in your garage?Know you're never going to get back to that restoration project?Want to get rid of the garage find?I'm looking for a SV Project Car for a reasonable price. What I'm looking for: Caterham Seven SV - in any road specThe car doesn't need to be road worthy, but does need to have been registered at some time with the DVLA.No need for engine, gearbox or cooling system but I'll find a home for them if the car has themIn fact all I really want is a chassis with as much of the rest of the car as possible (minus engine/gearbox/cooling)...... but I'll consider any SV project and maybe take it off your handsI've had some feelers out with dealers for such a car for a while but nothing much has come up. There have been a few S3 projects come up but no SV's yet. So, realistically I'm not expecting a rush of offers, but if you don't ask you don't get. It also means I'll probably refresh this request every few weeks to keep it visible to possible options. If you're looking to get rid of an SV that is in need of some attention then please get in touch on this thread or send me a message. thanks, John

Hi All, as of Thursday evening, July 21st it seems that some files are still uploading to Dropbox. Hopefully the upload should complete in the next few hours. John

Updated #26 to include GoPro7 transfer speeds. BTW... I'll be at Gurston Down on Sunday to watch the fun. I'll have some GoPro's and DJI Action 2 with me if anyone competing wants to see them. I'll also pack some 360 cameras if that's interesting to anyone. John

Hi All, I must also confess that I only realized this was a Speed related post once I was most of the way through writing my last response. But hopefully its still useful to some. Mark (mph) makes some good suggestions I think - he and I regularly discuss cameras/tech in cars and I know he creates some great video and analysis from them. If a dedicated camera is still what you're looking for I can offer the following further thoughts on action cameras... Firstly a general thought: The GoPro 8,9 and 10 don't need a cage to attach them to anything. They have the GoPro"prongs" built in. The DJI Action 2 has magnetic mounting but I probably wouldn't trust it to attach to a roll-over bar. The DJI Action 2 mounts (non-magnetic) are good though. The lack of a cage on the newer GoPros really helps when handling the devices (IMHO). However, the battery doors are a fiddle and getting the sd-cards in and out of them requires patience and decent nails! Second point, the GPS sampling speed of recent GoPros is higher than it used to be. It's now 10 times per second (UPDATED: thanks Mark-mph), so its able to show better location at higher speed. It still has accuracy problems, but its now higher termporal accuracy and low spatial accuracy! I haven't done high resolution GPS testing on the GoPro 10 so can't comment on how accurate the GPS is now... but i hear its better than it used to be. So I guess (as you know) you have two options for reviewing video from an action cam quickly and here are some of my thoughts: 1. Review on device. The GoPro 9 and 10 have the advantage as they have bigger screens.The GoPro 10 has better slow-mo modes and you might consider recording a run in slow-mo to be able to review bits of the run at 200fps (for UK PAL mode), for instance, and really slow it down as you run through that section. Newer phones can do this now of course too.Reviewing footage recorded in slow-mo on the camera allows you to play at normal speed or 8x slower. This feature seems to work the same for GoPro 8,9 and 10.A usable 1080p @ 200 fps slow-mo is available on 8,9 and 10 (but can go to 2.7k on 10) 2. Review on a Phone/Tablet Remember that higher frames rates and resolution will create larger files and so take longer to transfer to the viewerIf you want to see video as big as possible then you can run the GoPro Quik app on an iPad and transfer your video to it - laptops obviously work too but you'll obviously need a cable to the camera or take out the sd-card and plug it into the laptop.GoPro 10 uses the newer GP2 processor (its a specialized GoPro CPU for imaging) which means the front screen video is less choppy and the user interface is snappier, it also boots up slightly faster. This is also what gives the GoPro 10 better slow-mo framerates.The faster processor of the 10 also means that video transfers to the phone/tablet are slightly faster with a GoPro 10 over 9 and 9 over 8.A 340MB (60 seconds, 4k/25, HEVC) file took this long to transfer wirelessly from camera to phone (iPhone 13 Pro):GoPro10 - 13secsGoPro9 - 17 secsGoPro8 - 25 secsGoPro7 - 25 secsProbably the fastest way to transfer files from a camera to a phone is to take the sd-card out and plug it into a card reader on the phone/tablet. Though this is always a tricky operation and if you're in the outdoors then I'd be worried about dropping the sd-card and not finding it again!Using live review on the GoPro Quik app on phone/tablet (wireless connection needs Bluetooth and Wifi enabled - though it creates a private Wifi, so no need to be connected to a Wifi network) gives a low resolution view of the video but is the fastest way to look at video from the action camera. You can scrub backwards and forwards quickly and then hit play at that point. This gives a much larger view on your phone than you would have on the camera itself thoughIf you want to do more than a quick playback then you have to download the footage to the phone/tablet (see wireless download speeds above).GoPro Live review does not allow you to change the speed of slow-mo footage when you’re looking at it on the phone. You have to download the video to the phone and then you can change the speed when editing... and only when you have a GoPro subscription. Downloading slow-mo footage to your phone (tested on iPhone) and then transferring to the default photos app on my phone will play the footage back at the slow speed only… i.e. 8x slower than normal speed.Summary of that last point… working with slow-mo when you want quick review on phone/tablet is tricky.If you’d like any other tests or comparisons doing then I can have a go.

Sorry to be a pain folks but in case any of you nodded off while reading my long post above, I added a summary at the bottom of it with some key thoughts :-) John

All the above make very valid points Justin, but I'll throw a few comments in too. Seeing as you're replacing an existing camera you'll know all about cameras on Sevens anyway, but I'll throw in how I use each camera in case its a scenario that affects your bying decision. I hope I'm not teaching anyone to suck eggs, that's not my intention. It's also worth pointing out to others who may not be as familiar with video in a Seven, that there are almost as many good ways of doing video on a Seven as there are people who do it. Everyone has typically found their favourite way of doing it... none are wrong per se. The subject is way bigger than a single BlatChat post, but I hope I can add something to the discussion. This is a really tricky subject, and is very dependent on what sort of scenarios you're thinking of. I use different cameras for different occasions, and have over 25 action cameras now! Don't judge me! For me there are five main scenarios: Short blasts (short outings or track)Long runs (touring not racing) where I'm really interested in making the best video I canLong runs (touring not racing) where I'm casually recordingItems where I'm talking to the camera making a commentary on something like a YouTube video.Taking video around the paddock or blat-assemblyAs Mark (mph) mentions though... the software on these devices isn't always great. It can be unreliable and the user interfaces can be a pain. You also have to factor in over-heating - something that's got worse in recent cameras. So, I have used and own: GoPros (from the 3 through to the 10, Max and Session), Insta360 (Go, GoII, RS, X2), Sony (ZV100), DJI (Action, Action2, Osmo, Osmo+, DJI Mic, OM1 to 5 and most of the Drones from the Phantom 3 through to the Mini 3 Pro). I've also tried DSLR's and MILC's to record the above scenarios too. This isn't meant to be a flex in any way, I'm just a bit of a nerd when it comes to video - as are others on this thread too :-) In terms of what works best, I can only say what I've found in these categories: Software reliability: I know lots of people have problems with the latest GoPro's, but its not really something I've suffered with. They do crash sometimes ( and will need the battery removing to reset them - which is a pain if you've got a harness on and/or can't reach it from your seat). As I say though, I haven't found them too bad and have definitely got better with more recent firmware on everything from the 8, 9, 10 and Max. The DJI Action 2s are definitely more reliable here though. Hardware reliability: overheating is the main worry here I think. An action cam is usually pretty robust and I've found the GoPros to be really good at taking knocks etc. In terms of the overheating the GoPro10's and DJI Action2's are really bad if you leave them standing around. GoPro even admitted that something like 99% of video shot on their cameras is for less than 2 minutes... so why worry about overheating! There's a really good recent video by a guy called David Manning on YouTube about it ( ), so go and check that out for more details. However, if you have either camera in the air flow of a Seven then I haven't seen them overheat - the air cools them enough. I've run them for hours and no overheating (4k/25). If you plan on putting them in your footwell or engine bay for instance then you may only get a few minutes of record time. It's also really important to keep the framerate down (that seems to be more important than resolution, though that does matter to some extent too). I'll talk more about frame rates and resolutions below. I also power my action cameras from external power sources when I'm recording in a car, but also make sure I keep the battery of the device in too.User interface: The DJI user interfaces are better than the GoPro interfaces. The later GoPros are much better than the older ones though. The Insta360 interfaces are probably nearer to the DJI in usability but they often have tiny screens that can be tricky to see (IMHO). However, I only tend to use the cameras in a few modes and I find I can set up each mode on the GoPro and switch easily between them - either on the camera or more often on the phone app. My Setups.. General I record all my videos at 4k/25 - I do 4k so I can crop in and stabilize when I'm editing and I do 25fps because I don't then get problems with banding or beat frequencies with UK lighting - we can get into the details of that if anyone's interested but I do it just to reduce the risk of it being a problem. I post videos at 1080p/25 but will soon probably go to posting 4k. As mentioned above, 720p is fine for TVs but for newer TVs and tablets etc, 1080p is a minimum - IMHO :-) I always power my action cameras from a battery or from the car battery through a 12v to USB adapter. I use the 3rd party GoPro side doors that have slots in them for USBC power (as mentioned by someone else too). For cameras that have some of the car in shot I will turn off stabilisation in the camera (I can add it in editing if I need it). If the car is wholly in shot (looking at me in the cabin) then stabilisation can be on but doesn't have to be. If its shot without the car in the shot (front grille for instance) then I turn on stabilisation. This can be a problem though as the camera stabilisation often doesn't track the scenary properly when going round corners.. I may just turn off the stabilisation here too and do it in post. Don't bother trying to use audio from an action cam that is anywhere near the air flow of the car. Use another device, and phone can work well there but there are lots of small recorders you can use from people like Zoom (not the conferencing Zoom), Rode, DJI etc. So for my different scenarios: 1. Short Blasts I tend to stick a GoPro 10 on the rollover bar facing forwards. I like to have the camera above the bar - that way I don't have the rear view mirror getting in the way of the sight line (where your eyes are looking when you're looking at the road ahead). I know others prefer to have the camera below the height of the roll over bar, but not me. I use a manfrotto clamp to attach the camera - its really sturdy and can be removed really quickly. I may also add a camera looking back at me as I drive - that would be a GoPro 10 too. That would be mounted to the inside of the windscreen - usually with a GoPro flat sticky that is tucked away behind the rear-view mirrow. I then use a really small tripod head to go from the sticky to the camera. I use GoPro's because there are apps on the App Store that can control multiple GoPros by Bluetooth.. and I can start and stop them all at once. The GoPro remotes can do that too now and I sometimes do that instead. For audio I use DJI Mics clipped to driver (and passenger) to pick up speech and I have another mic sat somewhere out of the wind just picking up engine tone. 2. Long Runs that I'm really interested about the video I typically have one camera on top of roll-over bar, one facing driver/passenger and a roving camera mounted to one of the front grille, rear wing or bodywork. All will be powered externally. All will be left running for the whole run - though I stop and start them again when I stop for a bio-break or fuel. Always check for bugs on lenses at this point too! Running multiple cameras means I have options to cut to and from them when I'm editing. It also means that if I get a bug strike or a battery/power go bad on me, or a memory card fill up, then I have other options to make the video from. Audio is like in 1 which is synced in post - Final Cut Pro. 3. Long Runs that I'm not so fussed about the video In this case I'll usually put a 360 camera on the roll-over bar, power it externally and leave it running. I can then chose my "shot" when I'm editing (front/back/side/pan etc). I like the Insta360 cameras better than the GoPro Max BUT the GoPro Max records for longer and I like to just leave my cameras running and sort out the video when I get home. I find that if I'm playing with a camera on a run then I'm not enjoying the drive as much... so I leave the camera running and have a big memory card in each of them. Some of the Insta360 cameras will only record a max of 30 mins, so they get ruled out for long runs. The long selfie sticks on the Insta360's are great fun though and their "stick removal" software is great. I also leave my cameras running because on a long run something will often happen and you wished you'd had the camera recording. Some cameras allow a pre-record feature that records a few seconds before you press record as well but in a Seven its not always that easy to find the record button (however you do that) when you're driving. These pre-record features will hammer the battery though... almost like doing a full record, so beware of that. I've had birds dive-bomb the car, sheep run out in front me and recently an amusing incident bumping a car that all would have been missed if I hadn't had the cameras running all the time. I might rig up audio as in 1 but sometimes just go with whatever the camera mic picks up (and assume I'm going to junk the audio and just put music over the top). 4. Items talking to Camera as the driver I tend to use a GoPro 10 here attached to the inside of the windscreen and looking at me or me+passenger. I find the DJI Action 2 is bigger (with the additional battery bit) than the GoPro and so obscures my view a bit more - I also like to remotely control the recording and that's a bit easier with the GoPro remote - though both have good phone apps... however, powering on your phone, launching the app and connecting to the camera to press record takes longer than using a GoPro remote. Sometimes I use the audio mod on the GoPro10 and have something like the DJI mic plugged in but often I want the camera to be looking at me from being mounted on the windscreen (in the center for me and passenger, passenger side if its just me) and I don't like the audio mod because it make the install too bulky - especially with the GoPro 10 as they're now larger than previous GoPros. You can get away with using the audio from the GoPro for these pieces to camera as long as the camera is out of the wind flow. For audio here I'll have a DJI Mic clipped to me if I have the door on, and a cheek mic plugged into the DJI Mic if I have the doors off. With all these audio devices running I just sync the audio together in Final Cut Pro when I'm editing. The Rode Wireless II's are also great mics for this purpose but I now like the DJI Mic better here (also... I also found the Rode Wireless II's would start to clip the audio if I had the doors off and on full blat). With a cheek mic I can record good spoken audio even with the doors off and at full blat - when I can't even hear myself talk and yet I can still record good spoken audio - if a bit shouty!. 5. Walking around paddock/assembly-point I tend to use my iPhone for this sort of stuff now. If I'm doing a "top job" for the Club then I'll take a Cannon mirrorless camera (MILC) but iPhone's are pretty good. I use a DJI OM5 gimble if I really want smooth walking shots on the phone... but thats a bit overkill. You have to be careful with action cameras in this scenario because their focus ranges aren't so good... so walking around a paddock with a Gopro and trying to "VLOG" with it will often result in you being out of focus. For audio I use the DJI Mic again. They're brilliant. And of course if I'm doing something like the Speed Championship lunch presentations then I'll take a couple of MILCs and use GoPros and 360 cams as backups. I'll also take a lot of radio mics. along with paracetamol for the inevitable headache after doing a one-man shoot! :-) So that was a bit of a brain dump... sorry! In summary: GoPro 8 is a good camera, 9 is better and 10 is better stillthe front video screens on the 9 and 10 are really useful10 has much better slow-mo modes if that's your thang!audio is much better on 10 than previous cameras (but see point below)detachable lens cover on the 10 is also really good when a camera can be hit by bugs and stones (8 and 9 have fixed lens glass covers)DJI Action 2 is as good as a 10 but there are pro's and con's to eachThe GoPro "Bones" (it's a stripped down 10) camera might be coming to the UK at some point. It's not cheap but it has the option of having a hard wired record start/stop. So it could be easily wired into the ignition so it would start recording at the start of a run and stop at the end... no need to remember to hit record.Don't expect to get any internal audio from an action cam when fitted to a Seven in the air flow360 cameras are now becoming a really good way of doing video on a Seven but you need to get one of the newer ones if you want decent results (but there's A LOT MORE faffiing about needed once you've done your recording)Finally if you're in the market for a top of the range camera then don't forget that GoPro release new ones each September time. They are due to release a Hero 11 and probably a new 360 camera this year. There is also rumour of a high end camera that is coming from them this year too (they already released a bare-bones camera that some were hoping would be a new Session, but it isn't, so don't hold your hopes up for a new Session any time soon). John

Hopefully this will help and not hinder. It's for a dry-sump 420 on the oil side but I think should help explain the water cooling. https://purplemeanie.co.uk/index.php/2017/09/23/build-session-17-5-caterham-420r-water-and-oil-overview/ John

Mark, I’ll let others say whether they’ve taken things any further… but I think most people who try have contacted me and I’m not aware of anyone actively working on it at the moment. I was contacted by someone about 6 months ago who was looking to get into this but I didn't hear any more after the first few conversations. There was also someone who created their own data dashboard in a car about 18 months ago using the code we developed. Getting info from the ECU isn’t too big a problem now we have the protocol decoded, especially with your development experience. Changing the ECU mappings is a whole other thing... as factory ECUs are locked. Look forward to seeing if anyone else has moved things forwards. John

#3... when I find something I'll let you know! There's obviously this site, but I'm sure everyone is well aware of it by now: http://www.dvapower.com/ems. Not strictly what you are after, but I thought it was a great read.

I'm sure there's lots of people on this website that know the basics (and probably many who know the detail) of how a carburettor works, but I found this video fascinating and gives a great sense of what's going on in a carburretor... The carb' they make is obviously very simple, but really demonstrates the concepts I think. There's something quite mesmerising about the slow motion shots taken in this video. John

You've all had a couple of days to find my other error. And the answer is: For those of you familiar with all the UK circuits, you will notice that the aerial maps of Cadwell and Croft are switched around at 0:32 into the video. I'll put a sticky comment into the YouTube video to tell people of the error. John

#11 Thanks Tony. There's always something I get wrong! . I watched the video many times to check for errors but that process is of course predicated on the assumption that I can spell :-) There's another Easter Egg error in that video that I don't think anyone has found yet - at least they haven't told me or made their find public to my knowledge. I only found it last week while working on the next Caldwell Park video. Unfortunately, YouTube doesn't allow me to replace a video with a "fixed" version, so it (and the "screwtanear") will have to stay and I'll update the video description - it's not a critical problem I don't think, but it is another mistake. I'll update you all here in a few days, on what I got wrong, once you've had a chance to debate it Now I've done it... I've baited you all to find countless problems now! John

Thanks for all the great comments folks. This post has been sticky for a while now, so I'm unsticking it and switching it over to the Track Forum. John

Good luck with the registration docs Graham. It was an interminable wait for me over Christmas. And thanks for taking the time to tell me about the blog. It seems an age since I did it and I'm glad its still useful. Happy Blatting! John

Graham, like OilyHands, I have some articles on my website looking at the protocols used by the MBE ECUs. There's probably way too much information there but I mention it in case you're that way inclined. There was also an article written about our findings in the June and July editions of Low Flying in 2020. You can find my ramblings here: https://purplemeanie.co.uk/index.php/2019/08/31/ecu-diagnostics-part-1-introduction/ John

Hi All, just a quick note to say there's a new club video up on YouTube. It's an introduction to this year's Castle Combe Track Day along with what to expect at a club Novices Track day. All participants of the event have been sent an email that includes a link to the video but I thought it might be of interest to all members. We're hoping to do videos for other track days through the year - I can't promise we can manage to do all of them, but we're planning on doing at least a few. It also serves as another example of what we'll be doing more of with YouTube. Here's some of what Simon wrote: Follow this link to view the video. As always, any questions then please reply to this thread, send me a DM or email to socialvideo@lotus7.club. Simon can be reached on trackdays@lotus7.club John