Tyres - questions from a newbie.

[Dannyboy]

Some advice please, I'm expecting abuse from a few of you however - here goes.

What's a good Class 3 tyre? Still Kumho V70r? I have 8" rears and currently 6" fronts running running 215 rears and 175 fronts. Will a 215 fit a 7" rim and under standard front arches on the front wheels with an ET28 offset? Clearance to the wingstay looks like it may be tight - just some advice before I head off and buy new tyres.

Also - what's a good compound? I've noted that Kumho do the V70r in 185/70/13 in K12..

 

Many thanks in advance.

 

dan

[Shaun_E]

Hi Dan - be good to see back

Your choice is between Kumho V70A super soft K11 or K12 compound and Avon ZZR A24 compound.

I've stuck with Kumho which offer predictable breakaway at the expense of being quite heavy. The Avons are much lighter but (allegedly - as I've only driven on them once in a Rob's Hayabusa car) can be a bit snappy. The Avon converts swear that they grip more quickly than the Kumhos but once up to temp the Kumhos are marginally better. So swings ands roundabouts.

As for getting the 215's on the front, they shoudl fit a 7" rim although 7.5" or even 8" is preferable - most of us are using 7.5". Offset is less important than back depth (distance from the hub to the inner rim) - you need to keep the same backdepth which in practice means adding width to the outer rim only. ET28 sounds like the standard offset so will have 1/2" added to inner and to outer compared to 6" rim which may put the inner of the tyre too close to the wing stay. You'll also really need wider front wings than standard.

Shaun

[Mark Durrant]

Dan

Not sure on the clearance on the front wingstay but you should be OK with a 7" front rim. If you want a set of Khumo's call Mel Williiams on 07811 269500 and tell him I sent you. The V70 is available in a supersoft compound.

Alternatively you could fit a set of ZZR's in A24 compound which will fit your wheels/stays 185 front and 215 rears.

Do you still want the petty strut?

[Richard Price]

Dan,

I've run V70A's since moving to class 3, and have always run 215's all around in the supersoft compound (K12 or K13 from memory).

It's just about possible to get 215's under standard wings, but it's a bit of a squeeze, and you're likely to have to bend the stays a little, and remount the wings. I think you'd just about get away with 7" wheels, but 8" is just about ideal.

Matt Jenkins has stuck with using 175's on the front, and it does not seem to have held him back much....

'not sure on the offsets you'd get away with.

It would appear that there is change ahead, with most of the current list 1B tyres having their E mark's removed, and thus no longer strictly road legal, and being moved to a new list 1C. It's not really clear what the full implications of this are yet, but we may be forced into using much less sticky tyres next year.

Why not wait a year, or, better still, try class 2 again

 

[Dannyboy]

Mark

Apologies - and yes. I will be heading south fairly soon to pick up my cage from Copthorne, unless you are ever in Birmingham?

Richard - will heed the advice - I'm coming back this year for some fun - I haven't done anything for 3 years so dont' expect much! Will probably only be for this year as I'm hoping to sell the car and go racing again in 2016. Must catch up sometime - I appear to be upsetting the locals in your area by closing Stoke Road.. ;-)

V70's it will be then. Sounds like 175/ 185's on the front will be the way forward rather than get too involved in bending stays and potentially replacing wings purely for sprinting.

 

dan