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Re: Tyre Test



At 11:26 AM 10/4/00 +0100, Martin Fay wrote:
>      Any chance of a mailshot summary for those of us without web access?

Well, you won't get a lot of the individual results as the are graphical 
bars, but here is the rest.

- - Eric

We used the sports tourer benchmark Honda VFR800 and the new pretender - 
the heavier but quicker Triumph Sprint ST. They were fitted with the kind 
of datalogging equipment race teams use, to help our riders check every 
detail of the way the tyres performed over lap after hard lap of 
Bruntingthorpe Proving Ground. We chose Bruntingthorpe because conditions 
reflect those you find on the road

** 1st ** Avon Azaro II 98%

Recommended tyre pressures (lbs/sq in):
Front: 36 Rear: 42
Fastest lap  Marc: 2:09.30 Keith 2:10.54
OVERALL  98% Just as good on the Sprint
(ST Comments)
Marc: These behaved exactly the same on the Sprint as on the VFR. All 
comments apply. And the scores are identical, too.
Keith: These are my favourites of all the tyres here - but it is amazingly 
close. Comments and marks as the VFR.
(VFR Comments)
Marc: These suit the bike in every aspect. There's a tiny bit of movement 
out of corners, but it's fun, not scary. No complaints at all about grip, 
feedback, stability, turn-in time, or corner speed. Brilliant.
Keith: The tyres' profiles are just flat enough for utter stability and 
predictability going into bends and sharp enough for speedy steering. 
They're excellent and show Avon's extensive redesigning of this tyre over 
the past 12 months has paid off. I can't fault them.


** 2nd ** Pirelli Dragon GTS 95%

Recommended tyre pressures (lbs/sq in):
Front: 34 Rear: 39
THE FACTS
Fastest lap  Marc: 2:13.60 Keith 2:13.12
OVERALL  95% Solid stability
Marc: The Sprint is a slow turner in corners but the Pirellis make it even 
slower. Still, that doesn't mean spirited bend riding becomes a chore. 
There's plenty of grip, they're very predictable and behave quite well on 
overbanding. Only a 150mph bridge leap would upset the bike. Comfort is good.
Keith: They allow the entire underside of the bike to drag the ground. 
Feedback is good and the construction of the carcass makes for a very 
comfortable ride, especially considering the Triumph's rather squidgy 
suspension. I'd have preferred them to turn just a touch quicker.

** 3rd ** Michelin Macadam 91%

Recommended tyre pressures (lbs/sq in):
Front: 36 Rear: 42
THE FACTS
Fastest lap  Marc: 2:10.24 Keith 2:11.19
OVERALL  91% Cornering instability
Marc: These squatted and weaved out of bumpy bends. They definitely ran 
wide a number of times and, although they were generally stable and grippy, 
I felt cornering stability could be better. The lap times were good but the 
tyre isn't the best choice for a Sprint for the road.
Keith: There is a hint of understeer. They also tended to drift 
fractionally in tight, flat bends, extending the racing line by around 12 
inches. Fine for hard road use at sane speeds, but there are better.

** 4th ** Continental ContiForce 90%

Recommended tyre pressures (lbs/sq in):
Front: 36 Rear: 42
THE FACTS
Fastest lap  Marc: 2:09.97 Keith 2:11.08
OVERALL  90% Very fast and suits the Sprint
Marc: A blisteringly quick lap, only a few tenths off the fastest time. The 
tyre is brimming with grip and the compliant carcass clearly suits this 
type and weight of bike.
Keith: I also found these quick, but not to the same extremes as Marc. They 
are just as good on the Sprint as they are on the VFR. But I still can't 
get to grips with them on overbanding. Had they coped with this, they might 
well have got among my top three.

** 5th ** Dunlop D207 89%

Recommended tyre pressures (lbs/sq in):
Front: 34 Rear: 42
THE FACTS
Fastest lap  Marc: 2:12.00 Keith 2:11.24
OVERALL  89% Poor stability - exciting ride
Marc: The D207s moved around a bit on the Sprint but turned into corners 
really quick. There was slight instability in a straight line. They were 
unstable exiting some fast bends but there was loads of grip and the 
feedback was good. This made them predictable.
Keith: The Dunlops on the Sprint were the least stable of all those tested. 
This isn't surprising as Dunlop supplied D207s. Many sports tourer owners 
may opt for the D204s instead. The D207s tip in really quickly and offer 
bags of grip. I thought the straight-line stability was fine.

** 6th ** Metzeler MEZ4 88%

Recommended tyre pressures (lbs/sq in):
Front: 34 Rear: 39
THE FACTS
Fastest lap  Marc: 2:11.21 Keith 2:12.05
OVERALL  88% Fast, but hard to trust
Marc: These moved around a bit going into and exiting corners, despite the 
similarity in carcass construction to the Pirellis. They were also a bit 
wallowy when powering hard and getting back upright. Again the front was 
vague. And the bike struggled to turn into corners on the brakes. Grip was 
good.
Keith: These simply don't talk to me enough. There's no disputing there is 
quite a bit of grip, but I don't get the feedback to know where it ends. 
The turn-in time is slow, as I'd expected. I'm disappointed with the number 
of mini slides I got when riding at ten-tenths. You can be quick on them - 
if you trust them.

** 7th ** Bridgestone BT020 86%

Recommended tyre pressures (lbs/sq in):
Front: 36 Rear: 42
THE FACTS
Fastest lap  Marc: 2:10.24 Keith 2:11.19
OVERALL  86% Great feedback, but they squirm
Marc: The Bridgestones don't suit the Sprint ST. If I hadn't known what I 
was riding on, I would have thought the Triumph and the VFR800 were on 
different rubber - the behaviour is that far apart. There was lots of 
squirm and movement in corners, which made what was actually a fast lap, a 
sphincter-contracting one. Straight-line stability was fine.
Keith: I squeezed the second-fastest lap times on the Sprint out of the 
Bridgestones but they squirm on bumpy bends. But the levels of grip and 
feedback are totally excellent. A fast but choppy tyre.


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