Kumho v70 tyres... (again)

Kumho v70 tyres... (again)

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Discussion

Eugene7

Original Poster:

739 posts

193 months

Wednesday 18th January 2017
quotequote all
Ok, I've been using Yoko A021R tyres for years, but as we all know they are no longer road legal...
With Eugene I prefer 185/70/13 tyres - they handle far better on an older 7, and I need the ride hight as we do a lot of fast road miles.

But, the actual question is, what compound to go for with the Kumho v70's?

All the reprobates in Le BOG Club would simply say soft, or even super soft, and smile wide until the tread ran out...



I'm trying to be a bit more thoughtful on what's best for fast road use, especially as we do a lot of hard miles in the summer across/around France/Spain, etc.

(Feel free to look at previous blatts: http://www.7-dna.com/forums/index.php?action=vthre... and the year before: http://www.7-dna.com/forums/index.php?action=vthre... )

I guess the choice is soft or medium?
Eugene is a 210BHP Zetec, with Ital live axle, and wide-track front.

Thoughts?

DCL

1,215 posts

178 months

Wednesday 18th January 2017
quotequote all
I used both soft and supersoft compounds and found it hard to tell them apart in terms of grip. Perhaps the supersoft switches on faster by half a lap or so. They get very soft and sticky and are worth a lot of time over any other tyre I tried.

I'm not sure how well they would stand up to road use but on track they wear well and seem to last much longer than you would expect. I would be happy to try the medium and hard compounds on the road but I'm not sure it is legal to fit new ones now.

Aeroscreens

457 posts

225 months

Wednesday 18th January 2017
quotequote all
The V70As have gone the same way as the A021Rs in that the MSA now list them under List 1c Tyres - Sports/Uprated Tyres
Suitable for Competition.

Does that mean that the V70As are also marked 'competition use' and/or 'not for highway use'? I, too, want something grippy to replace same tyres as Eugene.

Eugene7

Original Poster:

739 posts

193 months

Thursday 19th January 2017
quotequote all
I'm trying to check road legality...
The info available via different suppliers is rather confusing...


Eugene7

Original Poster:

739 posts

193 months

Thursday 19th January 2017
quotequote all
From Camskill:

Yes they are road legal, but you do need to inform your insurance company you are using them on the road as they are primarily a track tyre. and the E mark on track tyres is really so you can use them to and from a race track.

So that should be fine, as most Caterham insurance companies will understand their use.

Eugene7

Original Poster:

739 posts

193 months

Thursday 19th January 2017
quotequote all
And from Demon Tweeks...

Yes they are road legal.

With no comment on insurance, or any other comment at all...

fergus

6,430 posts

274 months

Thursday 19th January 2017
quotequote all
Surely if they're E (or DOT) marked and have the requisite land:sea ratio then the tyre is legal? It's a binary thing. They can't be 'sort of' legal.

I think if you were driving in heavy rain and had an accident, there may be an element of contributory negligence involved, but common sense would prevail as to when it's suitable to use them for most people.

How do the Avon ZZ-R compare the V70s?

Eugene7

Original Poster:

739 posts

193 months

Thursday 19th January 2017
quotequote all
Mmmm - seems 70 profile Kumho's are a bit like rocking-horse st...

So, what alternatives?
Should I just go 60 profile???
What about 60 profile 185/60 13 NANKANG NS2R? They are a lot cheaper too...

I really would rather stick with 70 profile, but if I have to I'll give 60's a go - but what tyres to suggest?
(Something other than Kumho, just as a suggestion...)

Eugene7

Original Poster:

739 posts

193 months

Saturday 21st January 2017
quotequote all
Have spoken to a number of the Kumho suppliers now, and it seems stock will be available beginning March...

Think I'll probably just wait.

Aeroscreens

457 posts

225 months

Saturday 21st January 2017
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Eugene, Any idea on price for 185/70/13s and what compound?

Eugene7

Original Poster:

739 posts

193 months

Tuesday 24th January 2017
quotequote all
Price is around £100 per... depending where you manage to source them.
I'm still faffing about soft or medium compound.
I don't expect to get that many miles out of a set, but intend to have fun!


BigCol

202 posts

282 months

Tuesday 24th January 2017
quotequote all
at £100 a corner, not so different to these, Steve...
https://caterhamparts.co.uk/zzs/5246-tyre-avon-zzs...

which have got reviews in terms of both grip and longevity... or are they too thin at 55 profile for Eugene?

Some Gump

12,671 posts

185 months

Tuesday 24th January 2017
quotequote all
Why not Avon's? Great tyre that lasts for ages.
Kuhmo v70 Better in the wet, but a decent drying session and they melt like butter...

Aeroscreens

457 posts

225 months

Tuesday 24th January 2017
quotequote all
Eugene, Thanks.

I'm familiar with the V70As as I've used both soft and super soft for sprinting albeit in 215 and 235 widths. thinking that medium might be a better bet for road use.

Eugene7

Original Poster:

739 posts

193 months

Wednesday 25th January 2017
quotequote all
Some Gump said:
Why not Avon's? Great tyre that lasts for ages.
Kuhmo v70 Better in the wet, but a decent drying session and they melt like butter...
Simple - because Avons do not come in the required size...

Eugene7

Original Poster:

739 posts

193 months

Wednesday 25th January 2017
quotequote all
BigCol said:
at £100 a corner, not so different to these, Steve...
https://caterhamparts.co.uk/zzs/5246-tyre-avon-zzs...

which have got reviews in terms of both grip and longevity... or are they too thin at 55 profile for Eugene?
No way an I ever putting 55 profiles on Eugene...
With the suspension setup correctly I'd hit anything bigger than a fag-but!


Some Gump

12,671 posts

185 months

Wednesday 25th January 2017
quotequote all
Eugene7 said:
Simple - because Avons do not come in the required size...
Why not just wind the platforms down? Takes 15 minutes, tops.. We used to have to move them to move between CR500 and V70 for wet - became quite routine. It really makes a difference when we did a full year of track days on 1 set of CR500 fronts, but ruined our first set of V70's in a day on a drying track (before we realised turning a platform was more cost effective!)

DCL

1,215 posts

178 months

Wednesday 25th January 2017
quotequote all
Some Gump said:
Why not just wind the platforms down? Takes 15 minutes, tops.. We used to have to move them to move between CR500 and V70 for wet - became quite routine. It really makes a difference when we did a full year of track days on 1 set of CR500 fronts, but ruined our first set of V70's in a day on a drying track (before we realised turning a platform was more cost effective!)
The problem is (for the purest) that the roll centre at the rear is defined by the axle height (de deion tube) and using a low profile tyre really need the suspension to run lower at the front to get the same balance. Ideal for track, but not for road.

Eugene7

Original Poster:

739 posts

193 months

Tuesday 31st January 2017
quotequote all
BigCol said:
at £100 a corner, not so different to these, Steve...
https://caterhamparts.co.uk/zzs/5246-tyre-avon-zzs...

which have got reviews in terms of both grip and longevity... or are they too thin at 55 profile for Eugene?
You posted that already... and I replied biggrin

Way too bloody small!!!

Eugene7

Original Poster:

739 posts

193 months

Tuesday 31st January 2017
quotequote all
Some Gump said:
Why not just wind the platforms down? Takes 15 minutes, tops.. We used to have to move them to move between CR500 and V70 for wet - became quite routine. It really makes a difference when we did a full year of track days on 1 set of CR500 fronts, but ruined our first set of V70's in a day on a drying track (before we realised turning a platform was more cost effective!)
As answered, for correct geometry you cannot just 'wind the platforms' up...
You need to set the correct front geometry first, and then set the back accordingly.
As a rule of thumb, the front lower wishbones need to the parallel to the ground.
(Just a rule of thumb, but that will get you close.)
I sent a lot of time getting my geometry right, and altering it just ti get more ground clearance is not something I want to consider...