Graeme Smith

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Academy/Classic Gradauates is 1:4.11, so there must be a lot of VX1600s running that. IIRC the brouchure said that was each 1000rpm = 20mph. [edit - but that's a 5 speed box 😔] Edited by - Graeme Smith on 19 Oct 2009 14:44:28

The battery earth strap on my VX1600 has been touching the exhaust manifold and melted through 😳 Currently patched up with tape, but where do I get a new one - I guess its a fairly generic part?

Or at the end of the first lap, someone who's mis-counted stands in the middle of the track and tries to wave you in, cueing panic braking not to run him down

Yoko A539s are about £35 each, 021Rs in 70-profile are about the same. Polley Motorsport would probably do free fitting if you can get to them (or a circuit that they are doing tyre service at - they do a lot of short ovals...).

I take it that's Avon CR322s? A long time since I've run them, but I think it was ~18psi on the road (24psi on the track)

I can't see the videos, but are you trail braking? If not, brake at your usual point - or perhaps a little later - and arrive at the turn-in point just a littlefaster than you want. Reduce the braking pressure and turn-in; being lightlyon the brakes will help with turn-in (though you won't have quick as much lateral, turning grip available so you'll have to be smooth). As soon as you've come all the way off the the brakes (just before the apex?), start pressing the throttle smoothly on - as JYS says don't press the throttle until you know you won't want to lift it any.

If it is wet, and you're on CR500s, make sure you get some heat into them on the green flag lap - drive it sideways

Or get the whole lot from Luke - exactly the same (apart from the price) except it says "Luke" rather than "Caterham" - which is good if your name is Luke!

I’ve been using the 4-point with plug-in crotch straps for 10 years, and was very happy until I heard the stories about what could happen to your meat & two veg in a crash. I needed new harnesses this year (again…) so went for (pricey) Schroth ones with separate crotch straps, which loop over the lap belts, and sit each side of your tackle. Only used them a few times and it’s a bit more fiddley than the standard Caterham/Luke one (which I generally only used the 4-point on the road and the 6-point for racing) – for road, when big crashes hopefully aren’t regularly on the agenda, use I’d go for 4-points (and maybe a plug-in – you can tuck it under the seat when you’re not using it).

We had this at Silverstone Stowe a few years ago - very worn CR500s are much better than brand new list 1A tyres in even torrential conditions.

Actually, they vary between less than £100 and thousands - I'm using an ATC-2000 at the moment (if I can find it before the weekend; if not, its my very obsolete ATC-1000...) which I picked up for about £60.

45lbft for live-axle

I've run sticky tyres on track without any halfshaft issues. 100ftlbs of torque sounds very low - that's what the standard VX1600 puts out. Off the top-of-my-head, I'd have thought there shouldn't be any issues (more than usual...) with 130bhp??

IMHO I don't think its a question of power; more torque and abuse (i.e. hitting kerbs on track).

McMillan Motorsport have just come up with a new (and relatively cheap) race catalyst exhaust system for Super and Mega-Graduates - might this fit the bill for you?

Doesn't sound like its the one you want - the one I have credit card sized but fits in a black plastic "box" usually on the rear panel (like here)

Pair of chrome 7 1/2" headlamps. Not OEM - "Wagner" with three "nipples" around the edges of the glass. A tenner plus whatever the actual postage cost is?

Brand new plastic reversing lamp lens, still in (Land Rover) box - £4 inc postage.

Andy, we use shaved A539s in Classic Graduates (hence Polleys can do them for you...), but its to prevent them overheating in 20 minute races. For a sprint, you want all the heat in them you can, so shaving could be counter-productive I guess it would give less tyre tread movement, but whether you'd be able to feel this/it have a noticeable effect on the times, I'm not sure. For what its worth, at most circuits we struggle to match/beat the old lap records set on CR322s - A539s are a much better tyre, but the old 70-profiles went faster than the 60-profile Yoko, due to the gearing I believe - dunno if this applies to sprints as well, where the top speed is usually lower. Edited by - Graeme Smith on 25 Feb 2009 13:51:43

I'd say that CR322s and their ilk (Yoko A539s, etc) are actually very good track tyres - they do have very limited grip, but this makes you think about how to drive the car well (in open series, drivers often say they need more power/grip, but actually they just need to make the most of the power/grip they've got). I like to think of it as like a 1950s GP car with a bit more power than grip Having said that, on the road - on a Seven - they can be quite limiting and a bit to much throttle/steering/brake can see you heading towards a hedge or worse. Yoko 021Rs have more grip (but not too much...) and are probably a much better day-to-day tyre. If I used my Caterham mostly on the road, I'd probably run it on 21Rs... And do bear in mind that 70-profile 21s are much cheaper than 60-profile in 13-inch (£35 vs. £65??).

I've passed plenty of Caterhams on "serious" track tyres whilst running CR322s and their ilk...

IIRC I was told at my Scholarship seminar, back in 1999, that there's a soft limiter at 6250 and a hard limiter at 6750 - but I've never felt that's correct. What I do know is that if you keep it in 4th down Revitt Straight (or Silverstone national Straight or...), it goes "burrr...burrr...burrr" about 6800 (though it depends on how accurate the rev counter is) - which is usually better than changing up 100 yards before a braking point. Max power might be at 5500, but I've always felt it better to rev the nuts off it then drop it into the next gear at a point where its going to pick up the torque/power curve nicely. TBH I don't look at the rev counter much - unless I'm really trying to avoid an unecessary gear change, there's no point taking it to the limiter (hitting it willloose a few tenths), so changing "about 6000" seems good.

Change up when it gets noisy (something between 6000 and 6500rpm), but its fine to occassionally go to the rev limiter to save changing up to fifth on Revitt Straight.

Take it out. It may not be perfectly corner weighted with the ballast removed, but its equally unlikely that you don't weigh the same as the previous owner. And putting a passenger in (or putting a bag of shopping in, or carrying a spare wheel...) will muck the corner weights up entirely (although probably not so much you'd really notice).