New front tyres to replace AO48's?

[AMMO]

Driving home last night on worn front A048's in the dark and on damp back roads I found myself reluctant to overtake. Bad night vision doesn't help but the car tramlines so badly now I could see myself ending up in a ditch so I just took it easy.

 

The car has 6" rims all around with 185/13" soft on the front and 205/13" mediums on the rear. The handling and grip are fine in the dry on smooth roads but still with a tendency to tramline badly. The car has been corner weighted to give the same weight on both front wheels. Toe out has been run from 0.25 of a degree to 0. Not much difference. If you hit a bump sometimes the steering changes direction. So maybe I have a some other issues too. Been thinking of taking the car to Staurt Faulds and letting him sort it out as I'm no suspension specialist. I still have the old forged top link with the aditional traingulation so maybe a trip to Arch to modify the chassis to take the later wishbones may be an idea before doing anything else.

 

Blackbirdman Matt lent me some 13" rims with some old Avon Turbospeeds and I'm sure the car felt better.

 

Been thinking of leaving the almost new 48s on the back and perhaps going back to AO21's on the front as I'm sure they weren't that bad.

 

Any ideas anyone? Thanks

 

 

Ammo

Raceco.com

[Molecular--Bob]

Mine did the change of direction with bumps and it turned out to be very worn bushes in the rear suspension, all of the A-frame bushes were particularly bad, so might be worth inspecting these as well.

[AMMO]

Thanks Molecular-Bob

 

Will check these.

 

Ammo

Raceco.com

[randybugger]

How old is your car?

mine is a 1990 with the funny A frame without the cross bar

made a massive difference when I had one welded on

 

Tony

[skydragon]

FWIW my 2003 ex-supergrad car fitted with AO48's tramlines very badly on roads which are not in good condition (on smooth roads or on the track they are great) . To the point I nearly left the road when overtaking once on a country road with a poor surface...

 

Reading some other posts, it seems this is how AO48's are. I'm not saying that your car may not have some other issues, but before you start taking things apart, I'd suggest you view the AO48 tyre choice as the main culprit.

[Shaun_E]

A048s seem to have very stiff sidewalls. I never really got on with them on the road and despite dialling out bumpsteer with washers under the steering rack and adding a bit of toe in they never inspired confidence on a bumpy B road. They are great on track though.

I have since tried Toyo R888s (admittedly in soft compound) and these were much better - the sidewalls seem more compliant which not only reduces the tendency to tramline but also improves the ride comfort.

I would be tempted to try R888s on the front and replace the rear AO48Rs with R888s when they wear out.

If you are feeling flush then a set of Avon CR500s will give you the best road experience - they are lighter as well as more compliant and IMHO are the best road tyre for a 7.

 

Yellow SL #32 - member of Drowned Rat Racing

 

Edited by - Shaun_E on 16 Oct 2008 13:30:56

[Markiebabes]

>Slight hijackI would be tempted to try R888s on the front and replace the rear AO48Rs with R888s when they wear out.

 

I was looking at doing this also but not sure as to the affect on handling ?

 

Anyone tried this ?

 

 

 

 

Mark

---

_{R400 MW 203 bhp of pure fun ( more so with Aero fitted )}

[The Polisher]

 

I agree wuth Shaun: R888's are far better for not tramlining and always worth checking the rack height for bump steer. Mine needed 5mm packing to achieve the best result

 

Dave H.

Mad about S77ENS

[Willie.]

Has anyone ever tried a different offset front wheel to see if it sorts this?

 

Projecting a line from top to bottom balljoint finds the point where it meets the road about an inch away from the centre of the tyre...if I remember correctly. Can check my drawing at home if anyone really cares.

 

I think this gives the wheel some leverage to affect the steering. If it was closer it may reduce tramlining.

 

Willie

[nickh7]

I was told dont mix these two what ever you do as they are quite different construction

 

 

 

Fuel your Addiction here

[Jason Plato]

I ran R888 and 48r front / rear and I couldnt tell at all.

 

I do prefer 888's tho. As sid earlier - softer sidewalls and they appear to offer more grip. Bloody hopeless on trac and loose all grip after 3 good laps

 

Taffia rear gunner

 

[RiF]

sorry to disagree but I don't like the 888's I much preferred the 21's 😬 Wet or dry they were great, car felt better, more grip (with 888's I can slide far more easily). Only good thing about the 888's is the ride is smoother due to the softer walls of and the price. I would go for either 21 or 48 but never the 888's again.

Ammo I would get the tracking checked as I think 888s will make it even worse.

 

RiF Driving one of the first Duratec 7, and building CA07BON for Henrietta 😬 😬 😬.for pictures of 7 and carbon andCA07BON

[db]

Hmm. I'm having a very similar issue. Changed from 539s to 48s and the most beautifully poised car has become a tramlining nightmare.

 

Had alignment checked by James W, and talking to Tony Bones about getting a full geo check done.

 

My ... Preciousss!

[Roadsport06]

Just swapped from A048 to R888 and they have been far better with a less firm sidewall. Cheaper for 14" ones too

 

BRG and Yellow nose now with added brooklands

 

[skydragon]

Bloody hopeless on trac and loose all grip after 3 good laps

 

Is that true? I thought Toyo 888 gave a similar performance and lifespan as AO48 on track ?

[AMMO]

Thanks guys all useful information.

 

I'm thinking CR500s at the front and see how I get on. Also look at all the bushes, bump steer and update to the later wishbones.

 

Need to get the chassis sorted as it's no fun to drive if the conditions aren't perfect.

 

The AO21s were better but I had about 70 bhp less and was running 185 tyres at the rear as well.

 

I've been told by someone who knows a lot more about this stuff than I do that I would be better off with 7" rims at the back. So might try that as well.

 

Thanks again.

 

 

 

Ammo

Raceco.com

[Nifty]

The Toyo R888s are very similar to Bridgestone RE720s in construction, so I'm told.

 

I have a set of RE720s on 14" rims for MOTs and road driving when my track tyres are looking a little dodgy. The RE720s are the best road tyre I've used.

However, I still have 032s on track (I've accumulated a little stock pile) and on the road they tramline like hell too. It is a recognised condition of 32s and 48s.

On the track they are great and a hell of a lot cheaper to wear down than CR500s.

 

 

Keep off the straight and narrow 😬

[Nifty]

Ammo,

 

I'll dispose of your 048s if you wish, save you the fee

 

P.S. How did you get on yesterday 🤔

 

P.P.S. Don't forget I have a set of 13" rims you can borrow next time you are mapping, save your tyres

 

 

Keep off the straight and narrow 😬

 

Edited by - Nifty on 16 Oct 2008 18:45:11

[AMMO]

Hi Nifty

 

Got on fine but after the great result with the 2 litre everything else was an anti-climax. It was just testing to confirm what we sort of already knew already.

 

Thanks for the offer of the wheels for the dyno. We could pick them up on the way through next time.

 

You are welcome to my old A048's as they have plenty of trackday tread left on them.

 

Ammo

Raceco.com

[Ozzy]

Been reading this with interest. As when my 539's wore out, I was persuaded to go for 48's (soft front, medium rear). However, yes the grip is really good, but like db, my car now moves around quite a bit, and sometimes quite violently.

 

Also, after 1 track day and 2000 miles, the rears are worn out already. And the fronts probably won't be far behind, and at £110 a corner, it could get too expensive So I've been contemplating where to go from here?

 

Should I stick some 888's on the back, and see how they go. But this would mean mixing them with the 48's on the front, while they last. Are they likely to last any longer than 48's anyway? Probably not I suppose, but at least they're £30 cheaper per corner.

 

Or, maybe go back to something else. Might not be quite as grippy, but as I'm 95% road use, would this matter too much? I do sometimes wonder, whether a slightly less grippy tyre would be better anyway, as it does tend to let you know when you're on the limit, and you've still got a chance to extricate yourself from that visit to the hedge! Where as, with something like 48's, you're probably taking the corner at such a rate, that if it does let go, it could get nasty!

 

I really don't know what to think at the moment, as there are such varying opinions regarding tyre choice.

 

Nigel.

 

 

 

 

[Willie.]

Men talking tyres is like women talking shoes...they all like doing it and its all about bargains and opinion anyway.

 

For what its worth, I find Toyo 888s brilliant, on and off track. I find that their biggest advantage is NOT the grip (Although it is excellent) but the feedback...they let me know exactly when the car is about to let go.

 

As my Blatchat name would suggest, I like being sideways, and find the 888 really nice and progressive. It doesn't get you to the limit and then put you backwards. I got over 5000miles (Road, all weathers) and a trackday (Hooning all day) on a set before they were no longer legal.

 

You'll get all sorts of opinions, the only one that matters is yours. Give them a shot. Worst than can happen is you flog them or scrub them off and decide you don't like them.

 

Willie

[db]

Ozzy - delighted to hear there's someone in the same boat.

 

I'm curious about trying the 21s and the 888s to see if they are any better. I've just fitted new 48s on the rears, but when the fronts finally wear down, I think I'll be looking at four corners of one or other of those two makes.

 

My rears have only lasted me the summer, which is - as observed - quite expensive for tyres that I'm not really enjoying! That said - I can barely find the limit of grip (or well I did a little at Millbrook).

 

My ... Preciousss!

[CageyH]

I use CR500's for the road.

Yes, they may be slightly more expensive, but they wear well, and were designed for the car.

 

I changed from A048's are too many close calls of the tyres trying to force me off the road into a ditch.

 

Only dead fish go with the flow....!

[AMMO]

Is Caterham Cars the best place to buy CR500s?

 

Anywhere else I should try?

 

Thanks.

 

Ammo

Raceco.com

[Shaun_E]

The only other CR500 supplier I have heard of is BMTR or I believe you can get them from Avon direct. As they are bespoke for Caterham I don't think you'll get them any cheaper but it may be worth a try.

 

Yellow SL #32 - member of Drowned Rat Racing