Graham Perry

I am facing a similar dilemma. My 1700 steel crossflow is no longer properly competitive in non L7 club sprints where some other kit cars are running various lighter 1600's with up to 230hp and electric flat shifts. I could go down the all ali big bore crossflow route but that is very expensive and would put me up into a class where it would be equally uncompetitive against even average Duratecs. Fitting a Duratec remains an option but I don't have the garage time that I once had and the conversion would take me too long due to it needing a re-skin. I think I am moving towards a decision to retire my seven which I have had 26 years, and buy a Duratec car to compete and then modify from a better equiped base car. I am being open minded, but Its replacement may not even be Caterham.

Thanks guys, SM25T, I will be in touch in due course about sourcing a pair of joints. I just need to make some space in my garage first.

Although my car is 1990 de-dion, we upgraded to the more modern 'non-trunnion' front suspension with swivels not long after it first became available many years ago My brother and I were checking the car over today and detected a small amount of up and down play in the swivel at the end of the lower wishbone that never used to be there. Based upon the knowledge of Blatchat is the wear likely to be in the spherical joint mounted in the wishbone or wear in the upright itself ? If it is the joint, can it be replaced or do I need to buy a pair of wishbones ? Are all the spherical joints the same or have there been various versions ?

What about the main rear light wedge shaped blocks ? Are these still the horrible heavy rubber stuff or have Caterham finally made something lighter ? Someone on here made up some lightweight ones a few years ago for sensible money so I fitted them. I saved a small amount of weight on my crossflow by replacing the heavy steel Alternator mounting bracket and its sliding belt adjuster with aluminium ones that were home made from ali billet. I cannot remember the manufacturer but I also saved a whole kg by swapping to a lighter weight electric fan which was also usefully slightly larger as Crossflow cooling problems have been endemic over the years. I seem to recall that someone identified that you could save quite a bit of weight expensively if you have an older car by going to the later driveshafts. The early model de-dion tubes where the dampers mount through the tube were much lighter than todays one as well. I have had mine crack tested (and welded) a couple of times and re powder coated and it has been fine. Some of us changed the rear calipers from the original Ford ones to non ventilated disc VW Golf calipers (I forget which model) which looked slightly different but were fundamentally the same with the handbrake built in, but were Ali rather than iron, and they represented a decent weight saving without spending fortunes for race ones. They just needed a small spacer from what I recall, but they wouldn't work with some wheels so were not widely taken up. There is some stuff in the archive about this For my crossflow though, the three biggest weight savings were, an aluminium 5 speed gearbox case, an aluminium bell housing and switching to the expensive 13 inch mag MB R500 wheels which even today surprise me how light they are.

Update, A nice strong mix of bicarb worked a treat and cleaned the acid bloom off nicely. Yes the ali is stained, but I know that I can tidy that up properly another time. We have just fitted the new battery and been for a spirited drive and the car is now ready for the weekend with the weather is set fair. The POBC as ever.

Thanks guys, I am planning a session Friday to tidy up the mess and fit a new Shield battery before my next sprint at Debden on Sunday. I got some bicarb so everything should be okay. I will revisit it over the winter as I have realised that luckily every part that appears to have damage is removeable and should take a gentle abrasive and polish to remove the worst.

It would appear that when I competed in my most recent sprint the 12v battery split and has leaked across the engine bay oxidizing the aluminium in various far flung places. I think the cornering forces of the car on ZZR's made it run everywhere. Does anyone know the best way to tidy up and neutralise the oxidation in some awkward corners before it gets worse ? I know that the ali will be stained perminently but I am wondering what is the best way to remove the long streaky white blooms of oxidation ? Inevitably I noticed this problem for the first time when I discovered that the starter would barely turn, not having used the car for a few weeks.

When mine broke down a few years ago, getting a replacement was difficult without spending a fortune on a geared race version. In the end I had a local alternator/starter repair company rebuild it instead. They mentiond to me, once they had rebuilt it, that my Caterham starter (circa 1990) is a bit of a hybrid design with parts from two more common lucas starters, but they had never seen one exactly like mine before.

My MOT man can barely press the clutch far enough to drive it due to my fixed bag seat But he has not so far failed it for anything like that and I always get a ticket every year.

Although it doesn't say it in the GTKY7 guide you should always spin the wheel a few times immediately after you have jacked it up on a Caterham and indeed any taper bearinged vehicle before testing the play at 6 and 12 o'clock to centre the bearing first. Many vehicles that show play immediately after being jacked will lose some of it after the wheel has been spun. Its one of the things they teach MOT testers.

Is Angelo still working ? He has done several heads for me over the years. All have been good.

Another simple test. Remove the covers for all the cells on the battery. Swich everything electrical on on the car. Then get someone wearing safety glasses to look at the cells while somone else cranks the car. If one cell is bubbling significantly more than any of the others under load then the battery is toast.

Spotted tonight on the 25 heading anti-clockwise. C7 *** It didn't look like the best of evenings for sevening, pitch black and loads of heavy traffic. Had you been to Dartford ?

You were heading South I am guessing between 7:30 and 8pm somewhere near Stamford. You wouldn't have seen me as I was in my Skoda BTW, your nearside rear lights were not working 🙅🏻‍♂️

When I built my car back in 1990 I had this same problem except that mine was dangerous. It regularly swapped ends under braking including on the road I did all of the advice above including, multiple bleedings, cornerweights, a move to softer pads at the front, fitting front four pot calipers (two different types), larger Triumph Vitesse front discs etc all improved it a bit. However it still occasionally had a habit of spinning when braking rather embarrassingly at sprints. The only solution was to fit a balance valve (which once adjusted was then locked) which did finally entirely cure the problem.