Kumho as per 3.5R vs Yokohama 3.5 ?

[PAJ]

I've learnt that 3.5R spec rears are wider, also with a mudguard to match, but what I don't understand is why the spec for a 3.5R is for the Kumho tyres, while its common to put Yokohama's on a 3.5
    If I go for 3.5R spec on my 310SC, will I have to decide between these two types of tyres ? I'm presuming that the reason isn't something as daft as the Yokohamas aren't made in the wider fit, I'd be surprised if they weren't

[John Scherrer]

3.5R Spec wheels are Magnesium 8x16" on the rear (same size wheel as normal 16" Option) and fitted with Kumho 245/45R16 Tyres. (Road Legal Track Tyre Option)

Normal 16" Option tyre is Yokohama A048 225/45R16.

The widest A048 16" tyre is 225, you'd need to go to 17" to get a 245 ..

225/45/16 has a diameter of 609 mm
245/45/16 has a diameter of 627 mm

That's an 18mm difference giving a 9mm ride height increase and a 9mm Arch Gap Loss.

So it needs a bigger/modified mudguard at the rear to give adequate clearance.

[wasp]

The flow seems to be going towards the Kumho's.

I'm going for the narrower width ones (same width as the A048's) when I've worn my set of A048's out. Apparently they have more grip than the A048's and wear slightly better.

Anyone who's tried the narrower Kumho's, feedback welcome.

Cheers,
Stu

[Toilet Duck]

[quote="wasp"]

Anyone who's tried the narrower Kumho's, feedback welcome
[/quote]

Same here. I'd particularly like to know what hot tyre pressures people run on track

[John Scherrer]

See Tom's Reply #2

http://www.atomclub.com/forum/index.php/topic,15025.msg263915.html#msg263915

[Toilet Duck]

[quote="John Scherrer"]
See Tom's Reply #2

http://www.atomclub.com/forum/index.php/topic,15025.msg263915.html#msg263915
[/quote]

I forgot I'd asked there!

Then again, it was a while ago so maybe there has been further tweaking and testing............ 

[Toilet Duck]

Holy thread resurrection!

I'm planning on swirching to Kumho once my AO48's are finished ("normal" size on the rears, not the wider 3.5R size), however the link above to the thread where Tom posted pressures appears broken :-( Can this be fixed, or a working link posted? If not can anyone give me an idea of the recommended HOT pressures for Kumho V70 on the Atom, particularly for track day use?

Cheers

[wasp]

27 psi all round hot on track.
Start at 24 front cold and 22 rear.
I know it is a lot higher than the yokos but it is the right level.
You can lean on them more than the yokos too, they really are a fantastic tyre.
Cheers,
Stu

[Toilet Duck]

Cheers Stu, much appreciated