This is a story from about three months ago, but
Continental's Grand Prix
(the regular Grand Prix, not the Grand Prix 5000)
has undergone a model change.
It's fine that the tubeless-ready version comes in 28C, 30C, and 32C sizes,
but having the tubed version available only in 28C and 30C
is quite an aggressive decision.
↑You're probably thinking "that's not aggressive at all — you're just stuck in your old ways with your own preferences and personal bikes!"
And you'd be right to think that.
For now, our shop
only stocks the tubeless-ready version.
↑The top image is the old Grand Prix,
the bottom is the new Grand Prix.
Both new and old use Black Chili Compound,
so the unique light-rolling characteristics
of Continental's premium models should be inherited
(I've used the old version,
but haven't used the new one yet, so I can't say for certain).
The outer packaging box is made of paper stock
designed so that even if a goat eats it,
it won't upset their stomach—
the so-called SDGs (Stomach Digestive for Goats
= digestive aid for goats)
type of paper quality,
which means the sticker that Japanese distributors attach
(→here) doesn't stick very well.
If these stickers come off and products sit on the shelf that way,
people might wonder if they're genuine
from an authorized importer or not.
So at our shop, we
re-attach these stickers firmly
with adhesive.
This is very recent news, but
a 25C size has been added
for the new Grand Prix tubeless-ready version only.
When I pulled the box out,
that sticker came out stuck to it,
dragging along.
The other day, I replaced
a customer's Grand Prix 5000
Transparent tire that had
worn tread with cracks in the grooves.
The Transparent, true to its name "transparent,"
has no rubber on the tire sidewall,
and when you hold it up to light and look from inside,
you can see the printing on the outside of the tire
shining through.
Naturally, the sidewall flexibility
is different from all-black versions,
so this isn't just a color variation of the same model—
it's a completely different character of tire.
Even for my personal bikes, at least on the front wheel,
I can't think of any other choice,
and I've used nothing but these on all my bikes.
These are the strongest clincher tires I know of.
But when I tried to restock,
the 25C and 28C sizes in tubed models
have been discontinued.
It's not just that distributors are out of stock—
they've stopped carrying them altogether.
I need to hurry up and strip the front tire off my Niner
and put it in my Akamatsu spare.
Man, this is a problem. I really don't know what to do.
If you want one, order soon!
Even if our shop stock runs out,
please don't suspect that I've hoarded them all for my personal use.
Okay, maybe just let me buy one.
The tubeless-ready version masquerading
under the same Transparent name,
has rubber on the inside to maintain
air retention,
making it a fake Transparent.
~ Bonus ~
↑This is the Record TLR, the tubeless-ready version
of Veloflex's lightest tire,
and when you look inside the tire, there's
a thin layer of black rubber on the underside of the tread,
but the sidewall is just carcass,
a completely crazy spec where they're relying on
fiber material to maintain tubeless functionality.
Initially, I added about 50ml of Effetto sealant
and monitored it, but
the next day it had lost so much air it went flat.
Even at 100ml of sealant, I couldn't stop the air loss,
and putting in 100ml ≒ 100g of sealant would make
using such a light tire pointless,
so I tried adding about 50ml of Stans' thicker sealant,
Race Day (formerly called Race Sealant).
For the basis that 1ml of sealant weighs about 1g
(→here).
As a result, the air loss did improve
to an acceptable degree for use.
Though to be honest, if you pump it to 6 bar,
you can ride it that day.
The liquid sealant on top continues
to bubble and leak from the tire sidewall.
The top image is taken right after inflating to 6 bar,
and you can see faint bubbling,
so the bubbles are slightly different shapes
between the two images.
After more than a day, when sitting at rest,
traces of sealant that leaked out flow
to the bottom of the wheel.
The top image shows the wheel rotated
halfway around from its resting position.
Sealant liquid has also started seeping
between the rim and tire.
I've been monitoring this for several days now,
and while both front and rear have the same degree of air loss,
only the rear wheel continues to leak.
Continental's Grand Prix
(the regular Grand Prix, not the Grand Prix 5000)
has undergone a model change.
It's fine that the tubeless-ready version comes in 28C, 30C, and 32C sizes,
but having the tubed version available only in 28C and 30C
is quite an aggressive decision.
↑You're probably thinking "that's not aggressive at all — you're just stuck in your old ways with your own preferences and personal bikes!"
And you'd be right to think that.
For now, our shop
only stocks the tubeless-ready version.
↑The top image is the old Grand Prix,
the bottom is the new Grand Prix.
Both new and old use Black Chili Compound,
so the unique light-rolling characteristics
of Continental's premium models should be inherited
(I've used the old version,
but haven't used the new one yet, so I can't say for certain).
The outer packaging box is made of paper stock
designed so that even if a goat eats it,
it won't upset their stomach—
the so-called SDGs (Stomach Digestive for Goats
= digestive aid for goats)
type of paper quality,
which means the sticker that Japanese distributors attach
(→here) doesn't stick very well.
If these stickers come off and products sit on the shelf that way,
people might wonder if they're genuine
from an authorized importer or not.
So at our shop, we
re-attach these stickers firmly
with adhesive.
This is very recent news, but
a 25C size has been added
for the new Grand Prix tubeless-ready version only.
When I pulled the box out,
that sticker came out stuck to it,
dragging along.
The other day, I replaced
a customer's Grand Prix 5000
Transparent tire that had
worn tread with cracks in the grooves.
The Transparent, true to its name "transparent,"
has no rubber on the tire sidewall,
and when you hold it up to light and look from inside,
you can see the printing on the outside of the tire
shining through.
Naturally, the sidewall flexibility
is different from all-black versions,
so this isn't just a color variation of the same model—
it's a completely different character of tire.
Even for my personal bikes, at least on the front wheel,
I can't think of any other choice,
and I've used nothing but these on all my bikes.
These are the strongest clincher tires I know of.
But when I tried to restock,
the 25C and 28C sizes in tubed models
have been discontinued.
It's not just that distributors are out of stock—
they've stopped carrying them altogether.
and put it in my Akamatsu spare.
Man, this is a problem. I really don't know what to do.
If you want one, order soon!
Even if our shop stock runs out,
please don't suspect that I've hoarded them all for my personal use.
The tubeless-ready version masquerading
under the same Transparent name,
has rubber on the inside to maintain
air retention,
making it a fake Transparent.
~ Bonus ~
↑This is the Record TLR, the tubeless-ready version
of Veloflex's lightest tire,
and when you look inside the tire, there's
a thin layer of black rubber on the underside of the tread,
but the sidewall is just carcass,
a completely crazy spec where they're relying on
fiber material to maintain tubeless functionality.
Initially, I added about 50ml of Effetto sealant
and monitored it, but
the next day it had lost so much air it went flat.
Even at 100ml of sealant, I couldn't stop the air loss,
and putting in 100ml ≒ 100g of sealant would make
using such a light tire pointless,
so I tried adding about 50ml of Stans' thicker sealant,
Race Day (formerly called Race Sealant).
For the basis that 1ml of sealant weighs about 1g
(→here).
As a result, the air loss did improve
to an acceptable degree for use.
Though to be honest, if you pump it to 6 bar,
you can ride it that day.
The liquid sealant on top continues
to bubble and leak from the tire sidewall.
The top image is taken right after inflating to 6 bar,
and you can see faint bubbling,
so the bubbles are slightly different shapes
between the two images.
After more than a day, when sitting at rest,
traces of sealant that leaked out flow
to the bottom of the wheel.
The top image shows the wheel rotated
halfway around from its resting position.
Sealant liquid has also started seeping
between the rim and tire.
I've been monitoring this for several days now,
and while both front and rear have the same degree of air loss,
only the rear wheel continues to leak.