Khumo V70A Update

[PeterGinger]

Ok, there's good news and bad news. I'll start with the good, so I can delay the inevitable lol. I LOVE these tyres. I fitted them at the beginning of December. I've used them through snow, ice, rain, you name it. They start well from cold for a track tyre. A bit of wheel spin in snow and ice, but that's to be expected - nothing dangerous though. No aqua planning yet and its been pretty inclemant to say the least. They grip and brake like a dog with a very tasty bone. Its all good.

BUT
I went to Mark Fish today to get my geometry redone since the BG service in November - yes I know hehe. I was shocked and amazed when he took the wheel off and told me the front tyre was bald - literally slick. And I didn't use the car for roughly three weeks over Christmas. That's the hard compound on the front as well. So we are talking five weeks wear from the front tyres in winter. I'd imagine it would reduce to 3 weeks in the summer. I haven't done a single track day or airfield day - purely road use. The rears are still very good. But surfice to say I wont be keeping them long term. Back to Michelin I'm afraid. I can't afford £200 a month on tyres, however good they are. Sorry chaps, but I'm no longer your tyre guinea pig.

As an aside, I was ready to change to K-tek engine mounts, but mark told me they're fine, The strut top mounts are causing all the noise. So they will be done in due course.

 

[shiftspark]

Were both tyres or just one? they sound very soft if its was both!!


I am off to MF next monday for my suspension set up, what did he recommend/set it to?
PM if its Top Secret :!:
Cheers

 

[PeterGinger]

Well as my camber and toe was out from the bg suspension service, it was winter and I was to lazy to book it in as work was busy anyway. When they measured them they were Fr left = -1.5, Fr right = -0.5. The steering was well off centre to the left, so it was like boxing with the steering wheel to drive. The 1.5 side was the bald side. The other would be the same if the camber was correct. They were the hard compound on the front too. There is just too much weight on the front to run them. Id say track days will wreck them in a day or two.
I was saying how different the suspension felt with these tyres. I always wanted more rebound with the michelins as they were so wobbly, but with these I have too much. He recommended reducing the front dampers to 15 or 17 clicks from soft. I don't have his rear setup. I would try it, but I can't see the point now. Besides I don't want points on my licence. The tyres may be ok for track still, but not legal on roads. Its a shame as i love them even now. If only we could run slicks on the road lol :mrgreen:

What suspension setup are you getting from Mark. Cant wait to get the top mounts .

 

[Cue]

if your camber and toe is out, your tyres will scrub like crazy.... on top of that if they are a track orienated tyre, even hard compounds, they'll be softer than a normal road tyre so it doesn't suprise me that they've gone so quickly....

 

[PeterGinger]

Iknow but 5 weeks is obsene

 

[hoolio]

FIVE WEEKS, I know we all live and learn but I'd be spitting about that.

 

[PeterGinger]

Just call me THE TYRE SHREDD =D> ER

 

[George K]

As one of the other, very staisified users of V70A, I would agree that they will have a very limited life as a road tyre - but they are sold as a track tyre. The rubber is completely different - also I suspect that using them at temps below circa 6 C will completely destroy the rubber and could make it virtually disintegrate. Even storage advice is never to let them get too cold!!

As an aside for hill climbing I run soft at the front and super soft at the rear - works well and last about 2 seasons.

Did you stick to the reocmmended pressures? Kumho advised 26/24.

 

[PeterGinger]

Yep, that' s an interesting theory. It was below freezing for most of their life. The car isn't even garaged. But now I've been bitten, I'd be stupid to try again.

 

[shiftspark]

What suspension setup are you getting from Mark. Cant wait to get the top mounts .

Hi
I currently have -2.5neg and 1mm toe out at the front which feels very good but as its a competition car I may go to -3 at the front and Marks advised a bit less toe than standard at the rear.
He did say that he doesnt recommend the settings at the rear for road use !!

I will let you know what we set it at next week but these are for my 172 not a Trophy.

 

[PeterGinger]

ok. Whats best for toe on the front? Ive got 10-15 minutes out I think. Sometimes I think I might be getting tyre scrub, but it might be my imagination.

 

[shiftspark]

Well I went on monday a 500 mile and 9hr drive there and back But well worth it.(stayed at a travelodge for £15 over night)
Mark knows his stuff and a very nice fellow too!!
He checked my front and was happy with -2.5 neg but reduced the tracking to 12 min toe out, then checked the rear and after a chat set it to 10 min toe out (from 35 min in).
Then took it for a drive and was happy at that.
I have only had chance to try it at a brisk pace and it now turns in much quicker but it may give lift off over steer but I wont find this out until I get racing in april.
he DOES NOT recommend the rear set up for road use and puts this on the invoice.

 

[George K]

Colin, I agree with Mark's reservations - not sure I would be that brave on cold tyres (as in sprints/hills). For circuit work people have run up to 1.00 toe-out at the rear, which normally means with warm tyres, but even then the cars can virtually 'swap lanes'.

 

[shiftspark]

George, well there is only one way to find out :!: I seem to remember a 180 spin on the 1st corner in the Trophy last year.
Note to self, order full cage from MF :lol:

I think it will be ok George as it feels just like I used to have my mini set up. Mind you I think esses into chippys at harewood will be very interesting 1st time out.