Slipper man

Mike Barnby is a very nice guy, but his wheels (at least the ones he made for the original R500's) are not worth the risk. I had them on my car and suffered a wheel failure at Rockingham that caused a lot of damage to the car and could easily have resulted in a very serious accident. A number of other people (in addition to many racers) suffered similar failures (and yes, I did have them crack tested) and I personally don't like playing Russian roulette, which is what you are doing if you take those things onto a circuit. For road use, they are fine, and they seem not to suffer the same issues on other cars, but I wouldn't risk them on a circuit. I replaced all mine with the later spec aluminium wheels that Caterham racers moved to in 2003 or thereabouts. He was talking then about doing aluminium centres - I suspect they are safe.

Yo! See you there

It could also be the inlet air sensor (I have got through two of these. Also TPS is possible. If you raise the revs to say 2000, does it stay there cleanly or hunt? Best bet is to get it to someone with a diagnostic plug. I would say the two Steve's, but they are a long way from you

The difference in temperature readings may be something to do with where the measurement is taken - Minister told me that at 84 deg, the engine starts to retard the ignition to protect the engine. The head gaskets were never particular weak point on the R500,s (he says, having just had to replace a HG...) The problem with the first cars was that the cooling was marginal on what was for its time a very highly tuned engine. It wasn't helped by the fact that the standard radiator was initially the single pass item and there was no oil cooler. All this was fine for road use, but of course, many R500's spent a lot of time on circuits where the marginal cooling led to oil overheating and failure of the (OE Rover) big ends causing the blow ups that were infamous. Caterham (to their credit) retro fitted - free of charge - the early cars with the upgraded bearings, a triple pass radiator and wired the fan to the ECU. Some (like me) also fitted an oil cooler to be 100% safe. Following the mods, which became standard on later cars, their reliability has been excellent.

Is there a sender for the fan on the Duratec? On my K500, the fan is switched directly from the engine ECU. The temperature sensor that is fitted to the radiator is simply there to plug the hole! On my K500 the fan is set to come on at 77 deg, so I am surprised they let the Duratec run so much hotter.

Brilliant!!

Interested that you ran the spare engine up to temperature without putting it in the car. How did you do that?

The best thing is to buy some used slicks. They will last you a season, will out grip any road tyre and cost about £15 each

I suspect the life is 300,000km or so. The rest of a Caterham will probably have dissolved into rust before a prop shaft runs out of grease!

It is dead easy with the no. 1 and 2 pistons. All you need is two rods of the same lengths (like two old head bolts) and at 90 deg, both are level.

I just use thin (1 inch) webbing for this. The engine is very light so you can wiggle it aroud to get the best angles

I take a very simple line on this. These are Ford components engineered for a 300,000 km life when using the recommended fluids and pulling something much heavier than a Caterham around. I just follow Caterham's recommendations - the rest of the car will fall apart long before the engine or gearbox...

If you think about it, when the end of the throttle pedal is at right angles to the cable you will get the maximum TB movement for each degree of throttle movement. With mine I bent it forward so the the cable is at right angles to the pedal at wide open throttle. This way, the initial response is tamed a bit and you get sharper response at wider throttle openings. Mapping will solve a lot of problems though. The way you have described your issues, it sounds like the idle speed is partially set by the cable, which may well be throwing out the TPS and causing some rougher running at slow speeds. By coincidence I was at the two Steves yesterday getting mine tweaked and got a right roasting for balancing the throttles and idle speed! Apparently that throws all sorts of things out and the only way to adjust this stuff is via a laptop and the application of something Steve Greenauld seems to think I lack - skill! I think you should just take it to the Steves (having made sure the cable/pedal angles are appropriate) and I am sure they will sort everything else out for you

Don't worry - it isn't a problem. They all do it to some extent. IIRC, topping the oil reservoir up a bit normally stops it on mine. Jez Coates recommended an oil level of 9 ¾ inches from the base of the oil tank, or simply topping it up until some comes out into the catch tank when used hard. I think it is caused by the scavenge pump sucking air occasionally (again - not a problem).

I have an R500 with the same TB's. There are three things I did to get the car from where it was (fine on high throttle openings, but not great when pooling around gently): 1. Adjust the angle of attack of the throttle pedal so the first opening of the throttle was less abrupt (this made a big difference). The adjustment was by bending the end of the pedal 2. Make sure the bodies are balanced, just as you would a carb car. They are adjustable, just like carbs 3. The two Steves then transformed it by getting the mapping right It is now really smooth at low revs and easy to drive. And you can hold a constant RPM A further thought: mine had a real problem holding (say) 2,500 rpm when I went to get it MOT'd. When Steve plugged it in, he could see the TPS was faulty.

The KN wheels are fine for track use (but are aluminium alloy, not mag). The MB ones are not, as I know from experience. The resulting accident from the wheel collapsing at Rockingham could have been really nasty if it had happened ½ a lap later. Edited by - Slipper man on 1 May 2014 13:11:41

Steve did that for me when I arrived, but it is probably worth letting him know in advance that it will need to be done so that he knows and allows enough time.

Find a garage that is more used to/ friendly about Caterhams. Having said that, the readings do look rather odd and I wonder whether it might be in your interests to get the mapping sorted out by Steve Greenauld. You will probably find that not only will the car pass its MOT, but it will drive better too.

I think it all depends on how you will be using the car. As a circuit car, the sequential box will be much faster, but on the road it would be a bit of a pain compared with the standard H pattern box.

Not sure what they do now, but in the 1970's (e.g. types 908, 917), Porsche used locked diffs on all their race cars. IIRC, it was lighter, more robust and on a circuit made very little difference in their tests

Welcome back old man! What have you bought? And what else is in your toy cupboard?

Thanks. That's what I did. I thought long and hard about the order of redoing them and fortunately did what you advise. Lets hope the HG stays intact this time!

It took 0.75 turns to undo the cylinder head bolts....

Thanks Dave - that is very helpful. I was wondering how many turns it should take to undo them if they have been correctly torqued up. Roger - another year older but clearly not another year wiser. I wouldn't like to be in your shoes when Lynn hears what you propose doing to her dog!!

Thinking about it, I am not certain that I didn't. Trouble is, I am not sure I did!! Only solution I guess is to slacken them all off and tighten them correctly...