noddy tyre question

[stephen grant]

 

I've had my 021's for about 4 years or so, during which time they've probably done half a dozen or so track days. I'm now getting moosive understeer on track, which I certainly didn't used to have a year or so ago. The only thing that's changed with my car since my last track day (that i'm aware of) is that i've got possibly 10%-15% more power from the engine.

 

I'm aware that there are many possible reasons for my understeer and I need to address them systematically. I tried to guage my entry speeds against other caterhams and there didn't seem to be much in it, so I'm not sure that it's entirely bad driving. My question is; could my tyres have 'gone off' through age and heat cycling? There's plenty of tread still, the wear pattern doesn't look unduely worrying and I haven't made any front or rear suspension changes recently.

 

Thanks in advance

 

stephen

 

[Shaun_E]

I found that 21s went off after a few laps - they heat up very rapidly on a hot dry track. If they have survived 6 track days then you weren't pushing that hard and maybe the extra power and experience means that now they are overheating. At 4 years old though, the rubber has probably hardened.

 

Yellow SL #32 - member of Drowned Rat Racing

[stephen grant]

Thanks Shaun

 

Will get some R888's and try harder

 

stephen

 

[6speedmanual]

Can quite often get moosive understeer when doing the Elk Test, I believe

 

 

6SpeedManual

*tongue*There's no such thing as too much BHP per Ton 😬

[allen]

4 year old tyres may have become hard compound tyres - certainly a very noticable effect on 5 or 6 year old tyres.

 

allen

[Alias]

It may be that the issue was always there. It's just with the extra power, you can push your car harder through the exit of the corner which makes the issue look more obvious.

 

Other obvious things to look for when diagnosing understeer are the thickness of tge front ARB (thicker = greater understeer) and whether you've got a small amount of toe-in

 

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1800 Supersport with 6 gears and clamshell wings.

[mvh]

For what it's worth, when i got my car about 4 months ago, it had 4year old 032's ss! I did a couple of track days on them because they still had tread. Its an R400 and i was getting used to the extra power! It understeered like mad and i couldn't wait to get fresh rubber on it!! Now its great!! In my experience old rubber is no good.

[stephen grant]

 

Yup - i'm on the green arb, which obviously isn't helping me either.

 

So I've got an orange arb now to go on and i'm trying to find a set of R888's. Hopefully that'll sort it.....

 

Thanks,

 

stephen