Clincher tyre orientation

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction of
rotation. Nothing odd about that; I can think of lots of reasons why
it might matter for tyres like these with a tread patern. But another
arrow, pointing in the opposite direction, suggests that the approved
direction of rotation depends on whether the tire is used on the front
or the rear. Can anyone explain the reason for this? Normally, I
wouldn't bother, I'd just follow the instructions, but the rear wheel
has a flip-flop fixed/free hub that I will be using in both
orientations. Will I be risking death if I don't reverse the tyre
every time I flip the wheel over?
Thank you for your help.
Best wishes,
Nigel Grinter
Well-Spoken Wheels Inc.
www.wellspokenwheels.com

On Sep 13, 4:34*pm, wrote:
I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction of
rotation. *Nothing odd about that; I can think of lots of reasons why
it might matter for tyres like these with a tread patern. *But another
arrow, pointing in the opposite direction, suggests that the approved
direction of rotation depends on whether the tire is used on the front
or the rear. *Can anyone explain the reason for this? *Normally, I
wouldn't bother, I'd just follow the instructions, but the rear wheel
has a flip-flop fixed/free hub that I will be using in both
orientations. *Will I be risking death if I don't reverse the tyre
every time I flip the wheel over?
Thank you for your help.

It can matter if it had much of a pattern, which it doesn't. Mtb and
cross tires, including the ones on my own bike are directional with
prominent knobs, having better grip one way, and rolling more smoothly
in the other direction.

I'd imagine the instructions on those Dedas is mainly for
psychological and marketing advantage--but see for yourself.

On Sun, 13 Sep 2009 14:34:18 -0700 (PDT), wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction of
rotation. Nothing odd about that; I can think of lots of reasons why
it might matter for tyres like these with a tread patern. But another
arrow, pointing in the opposite direction, suggests that the approved
direction of rotation depends on whether the tire is used on the front
or the rear. Can anyone explain the reason for this?

Off road on loose terrain, the idea is to have the tire do a better
job for braking (front) or driving (rear).

I am doubtful it matters on the road or hardpack dirt.

On 09/13/2009 06:37 PM, Jobst Brandt wrote:
Phil W Leephil(at)lee-family(dot)me(dot)uk wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction
of rotation. Nothing odd about that; I can think of lots of
reasons why it might matter for tyres like these with a tread
pattern. But another arrow, pointing in the opposite direction,
suggests that the approved direction of rotation depends on whether
the tire is used on the front or the rear. Can anyone explain the
reason for this? Normally, I wouldn't bother, I'd just follow the
instructions, but the rear wheel has a flip-flop fixed/free hub
that I will be using in both orientations. Will I be risking death
if I don't reverse the tyre every time I flip the wheel over?

Front tyre optimised for braking, rear for acceleration. It used to
be fairly standard on motorcycle tyres designed for either front or
rear fitment to have directional arrows marked in opposing
directions depending on which end you were fitting it. "universal
fitment" motorcycle tyres are something of a rarity now though.

That was back when motorcyclists were still believers in oriented
tread patterns, something that passed into history a few decades back.

so when we see rain tires on f1 cars, that are directional, all those
millions of research dollars are just thrown away to make pretty
patterns for the spectators? jobst, you're being truly amazingly
pig-headedly stupid on this one.


On the road, slicks are the norm and should be for all dirt riding on
surfaces in which the tire cannot make an impression. For sand, no
directional paddle wheel tread is common on dune buggies and motos.

uh huh.



So you may lose a little traction on some surfaces if you run the
rear "backward". Only you can decide if it makes any difference in
your circumstances (terrain, riding style, etc.).

Just keep the religion alive by repeating its tenets. We have no
tests to show that any of the claims are true, only endorsements by
riders who have an opinion.

that is the credo by which you live jobst, not others. you keep spewing
the same old erroneous bull**** year in, year out. and you're still wrong.

jim beam wrote:
On 09/13/2009 06:37 PM, Jobst Brandt wrote:
Phil W Leephil(at)lee-family(dot)me(dot)uk wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction
of rotation. Nothing odd about that; I can think of lots of
reasons why it might matter for tyres like these with a tread
pattern. But another arrow, pointing in the opposite direction,
suggests that the approved direction of rotation depends on whether
the tire is used on the front or the rear. Can anyone explain the
reason for this? Normally, I wouldn't bother, I'd just follow the
instructions, but the rear wheel has a flip-flop fixed/free hub
that I will be using in both orientations. Will I be risking death
if I don't reverse the tyre every time I flip the wheel over?

Front tyre optimised for braking, rear for acceleration. It used to
be fairly standard on motorcycle tyres designed for either front or
rear fitment to have directional arrows marked in opposing
directions depending on which end you were fitting it. "universal
fitment" motorcycle tyres are something of a rarity now though.

That was back when motorcyclists were still believers in oriented
tread patterns, something that passed into history a few decades back.

so when we see rain tires on f1 cars, that are directional, all those
millions of research dollars are just thrown away to make pretty
patterns for the spectators? jobst, you're being truly amazingly
pig-headedly stupid on this one.

Well... car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Sep 13, 7:01 pm, Nate Nagel wrote:
jim beam wrote:
On 09/13/2009 06:37 PM, Jobst Brandt wrote:
Phil W Leephil(at)lee-family(dot)me(dot)uk wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction
of rotation. Nothing odd about that; I can think of lots of
reasons why it might matter for tyres like these with a tread
pattern. But another arrow, pointing in the opposite direction,
suggests that the approved direction of rotation depends on whether
the tire is used on the front or the rear. Can anyone explain the
reason for this? Normally, I wouldn't bother, I'd just follow the
instructions, but the rear wheel has a flip-flop fixed/free hub
that I will be using in both orientations. Will I be risking death
if I don't reverse the tyre every time I flip the wheel over?

Front tyre optimised for braking, rear for acceleration. It used to
be fairly standard on motorcycle tyres designed for either front or
rear fitment to have directional arrows marked in opposing
directions depending on which end you were fitting it. "universal
fitment" motorcycle tyres are something of a rarity now though.

That was back when motorcyclists were still believers in oriented
tread patterns, something that passed into history a few decades back.

so when we see rain tires on f1 cars, that are directional, all those
millions of research dollars are just thrown away to make pretty
patterns for the spectators? jobst, you're being truly amazingly
pig-headedly stupid on this one.

Well... car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.


Motorcycles also have two wheels, but are quite different from
bicycles as pertains to cornering and power.

I had an Avon tire on my short track (dirt flattrack) bike once. It
had long, deep, sharp 'V' angled tread symmetrically opposed on each
side - strikingly unorthodox. It would skate like grease into the
turn under deceleration, and could slide out pretty radically under
power if not hooked up, but when hooked up and accelerating out of the
turn, it definitely taught you to keep some weight over the front
wheel.

On 09/13/2009 07:01 PM, Nate Nagel wrote:
jim beam wrote:
On 09/13/2009 06:37 PM, Jobst Brandt wrote:
Phil W Leephil(at)lee-family(dot)me(dot)uk wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction
of rotation. Nothing odd about that; I can think of lots of
reasons why it might matter for tyres like these with a tread
pattern. But another arrow, pointing in the opposite direction,
suggests that the approved direction of rotation depends on whether
the tire is used on the front or the rear. Can anyone explain the
reason for this? Normally, I wouldn't bother, I'd just follow the
instructions, but the rear wheel has a flip-flop fixed/free hub
that I will be using in both orientations. Will I be risking death
if I don't reverse the tyre every time I flip the wheel over?

Front tyre optimised for braking, rear for acceleration. It used to
be fairly standard on motorcycle tyres designed for either front or
rear fitment to have directional arrows marked in opposing
directions depending on which end you were fitting it. "universal
fitment" motorcycle tyres are something of a rarity now though.

That was back when motorcyclists were still believers in oriented
tread patterns, something that passed into history a few decades back.

so when we see rain tires on f1 cars, that are directional, all those
millions of research dollars are just thrown away to make pretty
patterns for the spectators? jobst, you're being truly amazingly
pig-headedly stupid on this one.

Well... car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.

nate


http://www.trackaddix.com/?shop=1&subcat=4

hmmm, bridgestone, bridgestone... they're that bunch of
johnny-come-lately idiots from japan, that place with all those ****ty
"tech" universities, where they don't know what they're doing aren't they?

On 09/13/2009 07:36 PM, Dan O wrote:
On Sep 13, 7:01 pm, Nate wrote:
jim beam wrote:
On 09/13/2009 06:37 PM, Jobst Brandt wrote:
Phil W Leephil(at)lee-family(dot)me(dot)uk wrote:

I just bought a set of Deda Grinta tyres (something about the name
sold them to me) and was about to mount them on some rims when I
noticed an arrow on the sidewall indicating the desired direction
of rotation. Nothing odd about that; I can think of lots of
reasons why it might matter for tyres like these with a tread
pattern. But another arrow, pointing in the opposite direction,
suggests that the approved direction of rotation depends on whether
the tire is used on the front or the rear. Can anyone explain the
reason for this? Normally, I wouldn't bother, I'd just follow the
instructions, but the rear wheel has a flip-flop fixed/free hub
that I will be using in both orientations. Will I be risking death
if I don't reverse the tyre every time I flip the wheel over?

Front tyre optimised for braking, rear for acceleration. It used to
be fairly standard on motorcycle tyres designed for either front or
rear fitment to have directional arrows marked in opposing
directions depending on which end you were fitting it. "universal
fitment" motorcycle tyres are something of a rarity now though.

That was back when motorcyclists were still believers in oriented
tread patterns, something that passed into history a few decades back.

so when we see rain tires on f1 cars, that are directional, all those
millions of research dollars are just thrown away to make pretty
patterns for the spectators? jobst, you're being truly amazingly
pig-headedly stupid on this one.

Well... car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.


Motorcycles also have two wheels, but are quite different from
bicycles as pertains to cornering and power.

I had an Avon tire on my short track (dirt flattrack) bike once. It
had long, deep, sharp 'V' angled tread symmetrically opposed on each
side - strikingly unorthodox. It would skate like grease into the
turn under deceleration, and could slide out pretty radically under
power if not hooked up, but when hooked up and accelerating out of the
turn, it definitely taught you to keep some weight over the front
wheel.



you lie. the great and mighty jobst brandt tells us tread is irrelevant.

On 14 Sep, 03:01, Nate Nagel wrote:

Well... *car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.

Motorcycle tyres can hardly benefit from the file tread of a racing
bicycle tyre, it would be scrubbed off relatively quickly. A good
cyclist can descend quicker than a motorcyclist because of the better
cornering grip afforded in the wet allows the cyclist with a racing
tread to corner faster. Following a motorcyclist who is repeatedly
stepping out in the bends can be most entertaining.

On Sep 13, 10:04*pm, someone wrote:
On 14 Sep, 03:01, Nate Nagel wrote:

Well... *car tires are used/designed differently than tires used on two
wheeled vehicles, in that the wheel is always (roughly) perpendicular to
the road, unlike a bicycle or a motorcycle. *I can't pretend to be an
expert on motorcycling, but it wouldn't be surprising to me if the
tire/road interface acted more like a bicycle tire than a car tire when
it comes to hydroplaning.

Motorcycle tyres can hardly benefit from the file tread of a racing
bicycle tyre, it would be scrubbed off relatively quickly. *A good
cyclist can descend quicker than a motorcyclist because of the better
cornering grip afforded in the wet allows the cyclist with a racing
tread to corner faster. *Following a motorcyclist who is repeatedly
stepping out in the bends can be most entertaining.

Thanks for all the replies. Looking at the tread pattern on the
tyres, I can see how you might expect the preferred orientation of the
front tyre would aid braking and that for the rear give more traction
when accelerating, but those differences can't amount to much and
besides, for the rear tyre at least, I would expect that difference to
be erased within a few hundred miles of riding. So I guess I will not
be endangering life and limb if I use the rear tyre in the non-
recommended orientation.

Good to see my upper-case-challenged friend James Bean chiming in in
his usual temperate fashion. Jimboy, do you ever actually read what
Jobst says before uncorking the vitriol? What did Jobst ever do to
earn your unquenchable anger? I know that Jobst, like me, is getting
on in years, so perhaps he once inadvertently frightened you when you
were strapped in your stroller. Or perhaps you were injured when a
stroller wheel collapsed and you became convinced that Jobst was in
some way responsible for a design flaw? Seriously, though, Jim, I
think you should consider counceling.