Conti Ultrasport tyres a bit squirmy?

Just got a new set of tyres on the commuter (thanks Probikekit... only
4 days!)

As per standard practice, I bought the bottom-end of the price range
and ended up with a pair of folding conti ultrasports (23C). Putting
them on had me a little worried, as I had to be careful to get the bead
seated properly; I've never had that problem with wire-bead tyres
(first time I've used folding).

On the ride in this morning, they certainly felt different. Very plush
ride compared to my previous gatorskin/rubino combo, which I was
surprised at.

One slightly disconcerting thing is the way they handle.. they feel a
little squirmish in the corners... a sort-of early turn-in understeer.

Is this sort of handling difference normal.. or have I just pumped them
up to a different pressure?

duncan

Duncan wrote:

Just got a new set of tyres on the commuter (thanks Probikekit... only
4 days!)

As per standard practice, I bought the bottom-end of the price range
and ended up with a pair of folding conti ultrasports (23C). Putting
them on had me a little worried, as I had to be careful to get the bead
seated properly; I've never had that problem with wire-bead tyres
(first time I've used folding).

On the ride in this morning, they certainly felt different. Very plush
ride compared to my previous gatorskin/rubino combo, which I was
surprised at.

One slightly disconcerting thing is the way they handle.. they feel a
little squirmish in the corners... a sort-of early turn-in understeer.

Is this sort of handling difference normal.. or have I just pumped them
up to a different pressure?

duncan

I had just put these tyres on when I had my Big Stack(TM) in the wet.
Blamed it on all sorts of things before I realised it was just my
acceleration out of the corner that did it. It felt about the same as my
prev tyres... maybe it's just a narrower tyre?

Tam

Tamyka Bell wrote:
Duncan wrote:

Just got a new set of tyres on the commuter (thanks Probikekit... only
4 days!)

As per standard practice, I bought the bottom-end of the price range
and ended up with a pair of folding conti ultrasports (23C). Putting
them on had me a little worried, as I had to be careful to get the bead
seated properly; I've never had that problem with wire-bead tyres
(first time I've used folding).

On the ride in this morning, they certainly felt different. Very plush
ride compared to my previous gatorskin/rubino combo, which I was
surprised at.

One slightly disconcerting thing is the way they handle.. they feel a
little squirmish in the corners... a sort-of early turn-in understeer.

Is this sort of handling difference normal.. or have I just pumped them
up to a different pressure?

I had just put these tyres on when I had my Big Stack(TM) in the wet.
Blamed it on all sorts of things before I realised it was just my
acceleration out of the corner that did it. It felt about the same as my
prev tyres... maybe it's just a narrower tyre?

inhale
i've got these squirmy little geezers on my ride.
the do suck rather badly in the wet.
i've had a couple of big slides recently, like last nights big electric thunderstorm!

also the places where i have issues with traction is also dodgy bitumen + sand etc
no issues on concrete. ie, traction issues seem to be surface related.

however in the dry they are great =) no complaints there.
i run mine at 110-130psi. have handy floor pump
i'm a fat barstard so 120psi for 115kg is about fair.
in summer i can lay the bike right over, but in winter traction isn't there.
hmm .. i'm not sure if cold vs warm is a factor..
anyone have any experience with that?

i do drop the pressure when i know its going to be wet.to about 85-95psi.
this may or may not make any difference for light riders. i've found it to be
consistently better in the wet, but i'm not going as fast.
and yes it does understeer and oversteer, its an issue of uninflated tyres.
this is why i comtenplated the 26" bike and phats, but cost was out of reach.
i carry less when its wet or raining, take less risky routes and ride slower...

IIRR, sheldon brown says inflate you tyres, in PSI, to your weight in KG + 10.
ie, if you weigh 85 kg, inflate to 95 PSI. however this does depend on the tyre
type and use... i'm not sure how this applies on 26" phats tho... higher rated
rim, tube and tyre? depends on the cost i suppose. and breathe

cheers,

kim

"Kim Hawtin" wrote in message ...

IIRR, sheldon brown says inflate you tyres, in PSI, to your weight in KG +
10.
ie, if you weigh 85 kg, inflate to 95 PSI. however this does depend on the
tyre
type and use...

Crikey... I wouldn't dare follow that, I'd worry that the rubber would fold
over and rip from the rim.. I'm a fan of 120psi on the roadie, 100 on the
mtb with slicks..

You guys all wearing "Mortal Kombat" tshirts at work now Kim?


cheers,
GPL

GPLama Wrote:
"Kim Hawtin" wrote in message ...

IIRR, sheldon brown says inflate you tyres, in PSI, to your weight in
KG +
10.
ie, if you weigh 85 kg, inflate to 95 PSI. however this does depend
on the
tyre
type and use...

Crikey... I wouldn't dare follow that, I'd worry that the rubber would
fold
over and rip from the rim.. I'm a fan of 120psi on the roadie, 100 on
the
mtb with slicks..

You guys all wearing "Mortal Kombat" tshirts at work now Kim?


cheers,
GPL

I find that different tyres have different feel that may be different
to there stickiness, something like my training tyres conti -
gatorskins, do fine at 100 psi and feel solid, but michelin prorace
tyres feel squishy and need at least 120 psi, I think that 100 they are
fine gripo wise but the feel is disturbing.

So if the new tyres are lighter/less stiff in the sidewalls, may be
having this type of effect.


--
PiledHigher

PiledHigher wrote:
I find that different tyres have different feel that may be different
to there stickiness, something like my training tyres conti -
gatorskins, do fine at 100 psi and feel solid, but michelin prorace
tyres feel squishy and need at least 120 psi, I think that 100 they are
fine gripo wise but the feel is disturbing.

So if the new tyres are lighter/less stiff in the sidewalls, may be
having this type of effect.

this sounds like a more likely scenario.. I'll pump them up some more
this arvo before going home and see what happens.

duncan

GPLama wrote:
"Kim Hawtin" wrote in message ...

IIRR, sheldon brown says inflate you tyres, in PSI, to your weight in KG +
10.
ie, if you weigh 85 kg, inflate to 95 PSI. however this does depend on the
tyre
type and use...


Crikey... I wouldn't dare follow that, I'd worry that the rubber would fold
over and rip from the rim..

i take it you're a lot lighter than 115kgs? =)

I'm a fan of 120psi on the roadie, 100 on the mtb with slicks..

yeah me too. i've always "over inflated" my mtb tyres to get that
feeling you actually have tyres under you i've finally got my
SO to ride =D so more outlay on bikage is not far off! =D shes in
need of mtb tyres rated to 100 psi too! the rolling resistance on our
current bike is awful =/ all in good time!

You guys all wearing "Mortal Kombat" tshirts at work now Kim?

hardly. we're working on our own interesting thing.
hmm, maybe i should ask

cheers,

Kim

"Kim Hawtin" wrote in message ...
Crikey... I wouldn't dare follow that, I'd worry that the rubber would
fold
over and rip from the rim..

i take it you're a lot lighter than 115kgs? =)

For now yep..

I'm a fan of 120psi on the roadie, 100 on the mtb with slicks..
yeah me too. i've always "over inflated" my mtb tyres to get that
feeling you actually have tyres under you i've finally got my
SO to ride =D so more outlay on bikage is not far off! =D shes in
need of mtb tyres rated to 100 psi too! the rolling resistance on our
current bike is awful =/ all in good time!

I use IRC metro 1.5's on the MTB when the weather is a little less 'damp'...
they run nice at 100-110 PSI on the MTB, though they are very weighty.. I
get the same speeds on some super light knobbies, pity about the cornering..
oh, I never ride my MTB off road, it is purely for looks/training


cheers,
GPL

GPLama wrote:
"Kim Hawtin" wrote in message ...
i take it you're a lot lighter than 115kgs? =)
For now yep..

i'm aiming for 100Kgs =) getting there slowly...

I'm a fan of 120psi on the roadie, 100 on the mtb with slicks..

yeah me too. i've always "over inflated" my mtb tyres to get that
feeling you actually have tyres under you

that fluffy vague feeling leads to pinch flats! =(

i'm in need of mtb tyres rated to 100 psi too! the rolling
resistance on our current bike is awful =/ all in good time!

I use IRC metro 1.5's on the MTB when the weather is a little less 'damp'...
they run nice at 100-110 PSI on the MTB, though they are very weighty.. I

i'm heading in the same direction myself. my curent ones max limit is
60psi, feels good at 75-80 but i've dropped it back to 65 for now, feels
heavy but rides ok.

get the same speeds on some super light knobbies, pity about the cornering..
oh, I never ride my MTB off road, it is purely for looks/training

cornering on knobblies has always been my least favourite manouver,
especially in the wet!

cheers,

kim

On 29 Aug 2005 17:33:00 -0700, Duncan wrote:

Is this sort of handling difference normal.. or have I just pumped them
up to a different pressure?

IME width and pressure make far more difference to the feel of a road
tyre than anything else. I'd be surprised if any 23mm tyre at 120psi felt
'plush'.

--
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