Advice for a novice

[mg2959]

Hello, I've been lurking in this forum for a few months now, having a good read and trying to gain as much background info as I can before a prospective purchase of a Caterham.

I've been down to Caterham South and had a long chat to Callum, one of the sales guys. (Seemed like a nice chap .... but then he was trying to sell me a car!!) He was very helpful, talking things through and letting me jump in lots of differing models. I have more or less decided that i'm going to go ahead and order new. Supersport or Supersport R, S3 chassis, (Which surprised me as i'm 6'2" and 15 odd stone) Lowered floors, new GT Leather seats, side screen armrests etc etc.

The only thing that is really confusing me is the wheels. Size 13" or 14" or 15" then there are the 6", 7" or 8" widths?!?!?!?

Some are better for road use and others are better for track?

If i'm honest mine will be used 90% on the road with may be one or two fun track days a year.

I'm also stupidly struggling on what colour .... I know that this is purely a personal choice, but by Caterham basically saying they can do any colour actually causes more problems to me than it solves!!!

Hopefully I will be booking in for back to back test drives in both very soon - then it will be decision time. Unless they still have their ex demo R300 available

My Car history is pretty lame compared to some of you chaps, I've had the odd GTI, VRS, and I've mostly got my kicks from bikes for the last 15 years or so. The last time I drove a Caterham was about 20 years ago - It was a mates, and if my memory serves me right it was a 1700 Super Sprint - Vauxhall engine, with the flared front wings - what a blast.

Any advice you can give would be appreciated. Thanks

[Grubbster]

13's are widely regarded as the most suitable (certainly are on track) and they also open up a wider range of tyres you can choose which are cheaper (worth a thought in the future). As for width - 6" all round are fine, the 8" rears look nice but up to about 170 ish bhp they are not really needed. Not sure what wheels they can supply right now though - since K&N went under they seem to be struggling to get stocks back up with the new supplier, I've been trying to buy 2 13" wheels for months now

[downsman]

13 inch wheels are good for light weight, and there are 175x55 Avon CR500 or the relatively cheap but excellent 185x60 a021r yokohama tyres available.

However, low profile tyres on 13 inch wheels leave the ground clearance a bit tight, so some people use 185x70 a021r yokos.
Jacking up the suspension is possible but not ideal.

I have 14 inch wheels on my roadsport and a friend described them as the devils wheels as there is very little tyre choice. Either hard as nails ZV3s or a021r 185x60x14 which are excellent but £90+ a tyre.

15 inch wheels tend to be frowned upon, but do give a lot more options on tyres. I know several people who really rate Toyo r1rs which aren't too expensive and of course CR500s are available too.

I definitely wouldn't go for wider rears with the 1.6 engine, but haven't driven a Duratec so can't comment on that.

[mg2959]

Thanks for the advice guys. Looks like the 13" wheels are the front runners then.

[framerateuk]

Mine's got the 140 Supersport engine in it and runs on 15's at the moment.

Ride is quite hard, but not too bad, on track it's been excellent, but I get the impression that the wheels are a little too wide. Sides aren't easy to get unless you're really going for it, and when they do happen they seem to be quite sharp. There isn't a nice progression to loosing the traction.

I've just bought some 13x6 CXRs to put all round, and intend to get some CR500's in 175/55/13 all round too. That means I'm going to need to bump up the suspension a fair bit to ensure I've got the ground clearance (it's about as low as I can get away with on 15's at the moment and should ideally be a bit higher - a job for a free weekend it seems.

I'll report back about my comparisons between 15s and 13s once I manage to get out on track with them, but I'm hoping they'll be an improvement.

[mg2959]

framerateuk said:

I've just bought some 13x6 CXRs to put all round, and intend to get some CR500's in 175/55/13 all round too. That means I'm going to need to bump up the suspension a fair bit to ensure I've got the ground clearance.

Cheers framerateuk, I look forward to your update and comparison. Is ground clearance a real problem? I'm looking at 13's with lowered floors, and got quite a few speed bumps of differing shapes and sizes in my area which is now concerning me?!?!?

[TeflonT]

Assuming you do not have the 245 section CR500s, at the front the difference in dia betweem 15" CR500s and 13" is around 27-28mm so you need to raise the front by half that. At the rear the 195 section 15"and 205 section 13" are much the same dia. If you go for the 175 section on the rear you'll be raising the rear 14mm too.

This is all assuming you are at optimal ride height in the first place. A car that drops 14mm for the track might be a good thing.

[framerateuk]

mg2959 said:

Cheers framerateuk, I look forward to your update and comparison. Is ground clearance a real problem? I'm looking at 13's with lowered floors, and got quite a few speed bumps of differing shapes and sizes in my area which is now concerning me?!?!?

I'm not having any huge problems ground clearance wise, you just need to be sensible when approaching bumps. The big square bumps are best taken in the middle of the road, or as far over to one side as possible - otherwise you risk hitting the sump or the floors.

Very short speed bumps can be an issue for sump clearance, I could hear mine hitting some of them at Anglesey on the weekend, you just need to go over slowly. Most are wide enough to cause no problem though - again, just go slowly .

Like I said though, I'm definitely running a little low at the front, and am planning to raise the height a bit. I just need to find enough ballast to put in the car on my side, and convince the other half to sit on her side of the car while I work out all the heights!

[mg2959]

Thanks again, will be going very slowly over all 'traffic calming' measures that's for sure. Shame there are so many around where I live that have to be negotiated before getting out and on the open road.