AD07's in standing water...

AD07's in standing water...

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Discussion

jimmy_b

Original Poster:

14 posts

203 months

Tuesday 22nd November 2016
quotequote all
Hi all,

Just wanted to share a recent experience I had in my 111R, and ask if anyone else had experienced similar 'terror'!
Earlier in the year me and a group of mates (2x Elises and an Alfa GTV) did a road trip down to the Monaco Historic GP, returning over the Alps, covering 2000 fantastic miles in 5 days.

Car left the UK on Yokohama AD07 LTS tyres - fronts don't seem to wear at all, and rears were part worn, but certainly legal and all at correct pressures. Nearly 1950 miles later, within spitting distance of Cherbourg, the heavens opened and we were met with biblical levels of standing water.

At this point I admit that the rear tyres were barely legal, but the car became almost undrivable. Every change in the road surface (expansion joint etc) sent a solid thump through the car as if all compliance in the suspension had been lost. At one point I even stopped the car, convinced that something was broken. Equally unnerving, no matter how much I slowed, the rear of the car felt like it was moving around several inches left and right, even on dead straight road... I've had Elises for 10 years or so (111R for 5 years and a K Series before that) and I've never felt so intimidated by it.

My mate in his K Series S2, running equally slick Bridgestones, was experiencing none of this. The car doesn't tend to get used in such biblical conditions so its difficult to be sure, but its now on fresh AD07's and, in the dry at least, its back to being fantastic.

Has anyone else experienced this feeling on AD07's?
I know its a track-based road tyre but I can't believe just how bad they are in admittedly really wet conditions.

kambites

67,561 posts

221 months

Tuesday 22nd November 2016
quotequote all
I've been using AD07s on my Elise in all weather for the last nine years and haven't had any problems on standing water; they're appalling on snow, mind.

ETA: Are you sure you haven't somehow knocked the geometry out horribly?

Edited by kambites on Tuesday 22 November 16:03

The Bandit

788 posts

195 months

Tuesday 22nd November 2016
quotequote all
Same here with AD07/8s, great in all weather apart from snow/cold/ice.
How old are your dampers? How many miles on them?
Having said that any tyre on the wear bars in standing water aren't great...

gareth h

3,549 posts

230 months

Wednesday 23rd November 2016
quotequote all
I was out on Monday in biblical rain and was very impressed with how the AD07's performed, I think the problem will have been tread depth (mine are only 4k miles old).

cookmysock

844 posts

201 months

Wednesday 23rd November 2016
quotequote all
I ran ADF07's for a long time front and rear on my 2004 111R. Way better than the factory recommended Bridgestone Potenzas. I have driven it in all conditions (except snow) and even with low tread remaining, the car generally always behaved. I say generally because you have to be light on the throttle in heavy rain!

I never experienced the symptoms you have described. Sounds like some out of whack geometry which is pretty easy to get checked and corrected. Maybe some new bushings to tighten things up. Can you feel any issues in the dry?

You described a solid thump even over expansion joints. This sounds unusual and would not be related to the tyres on wear on them at all. Could be suspension issues - if you are on the standard bilstein shocks, they fail after a while with an aluminium disc corroding if I recall on the top of the piston.

Edited by cookmysock on Wednesday 23 November 23:16

james_gt3rs

4,816 posts

191 months

Thursday 24th November 2016
quotequote all
jimmy_b said:
At this point I admit that the rear tyres were barely legal, but the car became almost undrivable. Every change in the road surface (expansion joint etc) sent a solid thump through the car as if all compliance in the suspension had been lost. At one point I even stopped the car, convinced that something was broken.
Definitely sounds broken, I'd get that checked ASAP...

jimmy_b

Original Poster:

14 posts

203 months

Sunday 27th November 2016
quotequote all
Very interesting - seems like my experience is pretty isolated.

Car had a full geometry setup a couple of years ago via a well established fella in Southampton. Interestingly, at the time he mentioned my car was quite a long way out of spec so made quite a substantial change. I now wonder if he inadvertently set it up for the wrong model of Elise?

In the dry it's absolutely perfect - no issues with either suspension or mechanical grip... though car is now on good three. Equally, I've done a couple of hard-driven track days and it's behaved perfectly.

Looks like a geometry check may be worth doing now just to be sure...

jimmy_b

Original Poster:

14 posts

203 months

Tuesday 29th November 2016
quotequote all
Minor update...

I've done a little digging around on Google (yes clearly too much time on my hands) and found a similar post from someone on another Elise Forum - I've copied a summary below.

++++++++++++++++++++++++++++

Had my S2 Exige S since June. It had brand new AD048 LTS all round. Went touring up Scotland after, 1500 miles rear tyre tread was down to between 1.6 - 2mm! I checked pressure and they were pumped up to 40 psi. I then let them down to correct pressure. Then it started to rain endlesselly. I had to do 80+ miles with them in wet. Even on a dead straight road the back end was wondering around at anything above 55mph. The back end would kick out a little every time I drove over a new bit of tarmac. I was genuinely terrified. Got back home and had geo checked as I was convinced something was wrong. Turned out all was ok apart from rear toe in was 8 degrees on both sides! I am assuming that the wrong pressure and toe in is what wore the tyres out so quick. Are AD048 normally this bad in the wet?

++++++++++++++++++++++++++++

Appreciate its a different car on a different tyre, but this is very similar to what I experienced. It could be the geometry (I need to check my car), it could be the tyres or it could just be the driver needing to man up! I'll update if I ever get the bottom of it...


kambites

67,561 posts

221 months

Tuesday 29th November 2016
quotequote all
8 degrees! That's easily enough to make the suspension look obviously broken.

james_gt3rs

4,816 posts

191 months

Tuesday 29th November 2016
quotequote all
jimmy_b said:
Car had a full geometry setup a couple of years ago via a well established fella in Southampton. Interestingly, at the time he mentioned my car was quite a long way out of spec so made quite a substantial change. I now wonder if he inadvertently set it up for the wrong model of Elise?
Nope, you'd have noticed it straight away otherwise. Maybe worth jacking the car up and checking for play on the toe links? And see if the dampers are leaking?

gareth h

3,549 posts

230 months

Wednesday 30th November 2016
quotequote all
jimmy_b said:
Minor update...

I've done a little digging around on Google (yes clearly too much time on my hands) and found a similar post from someone on another Elise Forum - I've copied a summary below.

++++++++++++++++++++++++++++

Had my S2 Exige S since June. It had brand new AD048 LTS all round. Went touring up Scotland after, 1500 miles rear tyre tread was down to between 1.6 - 2mm! I checked pressure and they were pumped up to 40 psi. I then let them down to correct pressure. Then it started to rain endlesselly. I had to do 80+ miles with them in wet. Even on a dead straight road the back end was wondering around at anything above 55mph. The back end would kick out a little every time I drove over a new bit of tarmac. I was genuinely terrified. Got back home and had geo checked as I was convinced something was wrong. Turned out all was ok apart from rear toe in was 8 degrees on both sides! I am assuming that the wrong pressure and toe in is what wore the tyres out so quick. Are AD048 normally this bad in the wet?

A048s are semi slick track tyres, and at 40psi and 1.6mm tread would be a liability in the wet!

++++++++++++++++++++++++++++

Appreciate its a different car on a different tyre, but this is very similar to what I experienced. It could be the geometry (I need to check my car), it could be the tyres or it could just be the driver needing to man up! I'll update if I ever get the bottom of it...