Adjusting Camber

Adjusting rear Camber
Rear camber is really easy to adjust, and can be done in just a few minutes.

1. Remove the wheel. 
2. Loosen the four small bolts (unlike the picture, normally two of them are hex bolts).
3. Add or remove shim plates as necessary. Silver = 1deg, red =0.75, blue=0.5 and black 0.25. You can buy them from Caterham parts.
4. Be careful not to over tight the bolts, especially the vertical ones. 

Beware that if having a cross-ply setup with not much camber, be sure you have enough threads left on the horizontal bolts, or the wheels may fall off!

Adjusting front camber
Adjusting front camber can be a pain, especially the first time.

1. Undo the camber lock nut at the end of the upper wishbone.
2. Remove the wheel
3. Remove the wing stay by loosen upper ball joint nut, and then removing the stub axle nut. The indicator wires prevent from complete removal, but tuck the wing stay out of the way and try not to scrape the wishbone paint.
4. Undo the top ball joint nut until the nut is on the end of the thread.
5. Now split the tapered joint. This can be done in several ways. Personally I use a cheap tool which fits perfect used up-side-down! See picture. I've read about others who use a hammer!? Some use a bolt with two nuts against the hub (never tried it).
6. Remove nut completely and adjust camber. One turn equals .25 degrees of camber.
7. If you feel lucky, put copaslip on for easier dismantle next time. But beware - copaslip can make it really painful to screw back the wishbone to upright nut!
8. Stub axle 82Nm
9. Upright top ball joint 52Nm. 
10. Wheel 74Nm
11. Tighten camber lock nut

Note that camber affects toe, so if you adjust camber, you must recheck your tracking!

Trackday slicks part #2

I emailed Avon asking for recommendations regarding slicks on the CSR.

Hi Niclas,

As you probably know, the racing CSR run 9”X13” front wheels and 10.5”X13” rear, we developed some radial slicks specifically for this application for use in the CSR Eurocup.

195/530R13 A24 compound

250/570R13 A24 compound

With 15” wheels things are a bit more difficult. I would recommend using radials on a CSR as the car was designed to work best on them (most other Caterhams work better on a cross-ply) but unfortunately we do not make any radials in suitable constructions and compounds for this car in 15”. The cross-ply tyres you have a probably the most suitable we have available but again, these are not perfect due to the split of compound front to rear (A24 front A56 rear).

The cross-ply tyres will only require a small amount of camber, far less than the radial set-up the car would have been built to.

Sorry I can’t be more helpful.

Regards,

Xxxxx

And after a follow up question:

Hi Niclas,

I’ve done a little digging and you are absolutely right, they did run 7” and 9” which were a little bit narrow but seamed to work well.

We have replaced the 175/550R13 front with a 195/530R13 spec number 13800S – it’s actually the same size (don’t ask).

The rear 250/570R13 spec number 9906S is still current.

I’d go with the 7s & 9s and get the necessary rear brake changes done.

Hope this helps.

Regards,

Xxxxx

See also Trackday slicks part #1

Gotland Ring

A nice autumn trip to Gotland together with my family. Two full days on the track with nice sunny weather.

Gotland Ring is located on an island on the south eastern part of Sweden, and is one of the newest and most modern tracks in the country. It is a very technical track with hills and hidden corners, and takes lots of practice to master.

As usual, the day's first laps were the fastest, then downhill from there.I don't know why that is, if it is the car, the sun, the tires or in my head, but I can see that pattern on all track days.

Best time 1:30.59. A bit of a disappointment. It is better than last year, but my goal was below 1:30. I know that is possible, and now after a bit of log analysing back home, I know how!  I lose more than a whole second on the very last corner before the straight! Can't wait until next time.

I also found out that I need a little bit more neg camber all around, and a little higher tire pressures to avoid overheating - about 19.5 psi. Overall the car's handling is really good! The balance is perfect. But I still have problems with inner wheel spin on corner exit.

Nothing broken this time!? But I need a new set of tires...

Thanks to Gotland Ring - for being flexible and easy to deal with.

Limited rear droop travel

I noticed my rear droop travel was way too limited and suspected that could explain some of the rear inner wheel spin I have been troubled with.

My car is fitted with a Quaife ATB, and one of the "features" of the ATB compared to other LSDs is that if one wheel is completely unloaded, the ATB won't lock! So, when in roll while cornering hard, and the droop travel is too limited, the load on the inner wheel is reduced and the ATB is unlocked with inner wheel spin as a result.



More info about how the Quaife works

Here is a good article in Mark Ortiz Automotive CHASSIS NEWSLETTER describing what's happening when the droop travel is limited.

So now I have lowered the car with three complete turns on the spring platform on each damper.

I was at Mantorp (where else...) testing last week, and yes, the difference was obvious. No corner entry over-steer I've complained about last time, and the corner exits where a lot less dramatic. I think the inner wheel spin was reduced as well, but not completely. I've read on Blatchat that inner wheel spin is a common complaint on the ATB and what makes it not suitable for racing, and the solution is probably to change to a real LSD such as the Titan.

During the day I also experimented changing the rake to change the under/over-steer balance and found it to be a very easy and convenient way to quickly change the car characteristics in a few minutes. Just jack the front up and remove the hood and turn them with your hands. As little as an half turn each made a real difference. I made the car a little more tail happy and it did affect the lap times in a positive way.

But as usual...

That stupid plastic piece of tubing on the inlet was cracked, again. I tried to fix it with some isolation tape but it still leaked and sometimes the engine hesitatate at 6000 rpm as well as a notable lack of power. So no personal lap records today even if the chassis felt good.

Handbrake cable warning!

My handbrake cable was routed so it was in contact with the fuel tank. As a result, it the cable has dug itself into the aluminium and created quite a big scar in the tank!

So everybody out and check your handbrake cables!