The other day, I wrote about how the rear
Grand Prix 5000 S TR tubeless ready tire that had been sitting for about three weeks
lost its seal when the rim bead hook lifted,
causing the sealant to harden (→here).
After cleaning the tire and rim and adding sealant again,
I continued using it,
but today I noticed the rear wheel had a significant wobble.
There was a spot where it was jumping noticeably to the right.
However, when I put it on the truing stand,
the wheel showed almost no wobble.
The wheel in the image above is rotating.
It wasn't the rim that was wobbling—it was the tire.
This is the state of lightly touching the gauge of the truing stand
to the tire sidewall on the left side (non-drive side),
and in most phases of rotation,
there are spots that touch similarly lightly.
At the phase where it jumps to the right,
there's this much clearance.
I'm not sure if the tire sidewall casing has burst internally
and torn, stretching the sidewall,
but when I examined the removed tire,
the relevant spot on the tire sidewall was indented and pinched.
Before removing the tire, let me check how much the so-called 25C tire
has stretched after about six months of use—or rather, constant pressurization.
There was variation depending on the phase of rotation,
but the widest section was just under 26C.
This was surprising even to me,
but that wasn't the phase with the noticeable jump.
The air pressure limit was set at 7 bar (which is also the rim's limit),
and I would top it up whenever it dropped below 6 bar.
After cleaning the sealant off,
I weighed the tire.
Considering the slight traces of sealant remaining
and the fact that it was still damp right after water washing and wiping,
the actual weight is probably around 255g.
↑ The weight of the same tire when new.
I've been running it since June 30 of this year,
and in the linked article at the beginning,
I wrote something like "it's definitely going to last six months,"
but due to this unforeseen issue, it fell just short at almost six months.
After this, I was thinking of going back to using IRC's Formula Pro S-Lite
tubeless ready in 23C or 25C,
knowing that their lifespan is short,
but I have a tire already purchased for the next one,
so I'll use that first.
That tire is, as the title suggests,
the Grand Prix TT TR.
I will probably only ever use this tire once more.
It's a Continental tubular tire, and while there are multiple flagship models,
the pricing is identical across all of them—seemingly to indicate
that they're in the same class despite different intended uses.
Those were Competition, Grand Prix 4000 S II, and Tempo II—three models—
but Grand Prix 4000 S II was discontinued,
so the current flagship line is now two models.
The current MSRP for those is ¥17,727 before tax, but
this is a reverse-calculated figure derived from wanting
a tax-inclusive MSRP of ¥19,500
(strictly speaking ¥19,499.7).
When I looked up the 2013 Competition's MSRP,
it was ¥9,500 before tax with 5% consumption tax for ¥9,975 including tax.
Now, regarding this Grand Prix TT TR,
the MSRP is ¥15,455 before tax,
with a tax-inclusive MSRP of ¥17,000.
Strictly speaking that's ¥17,000.5, but
at shops selling at MSRP with POS systems that input prices
based on the pre-tax amount,
if you bought two at once, would it ring up as ¥34,001?
Who knows.
Anyway, setting that aside, there's a rubber strip
like a piece of kombu seaweed that has no tube sewn in,
just lying open toward the rim—
priced at the same level as a tubular tire.
That's hard to accept, and
considering the probably short lifespan,
it results in abnormally high running costs.
At this price point, honestly,
I'd rather spend that money plus a bit more on
a tubular tire for a tubular wheel,
so I might only use this tire once.
Not that I should be saying that as someone in the business.
If the tubular option were something never relevant to me,
it might have become a piece of equipment
kept continuously in reserve as a Sunday-best dress tire—
not in regular use but maintained available.
The sticker (→here) wasn't
on the box for this tire,
but of course it was procured from
the sole Japanese distributor of Continental.
The 5000 TT TR is a new model, so
it probably hasn't been applied yet.
By the way, Wiggle's international operations have ended.
The measured weight of the 25C tire after removing the instruction sheet
from inside the tire package.
The tire has PP banding wrapped around it, but
that weighs barely a gram or less.
IRC's lightweight tubeless ready model S-Lite
also comes in a 23C option,
with published weights of 205g for 23C and 220g for 25C.
S-Lite tends to have measured weights slightly lighter
than the published specs, so
weight-wise, with the same width,
they're about equivalent.
Incidentally, the published weight for the 5000 TT TR is
225g for 25C and 240g for 28C, so
this time I seem to have gotten a favorable specimen weight-wise.
After mounting on the wheel and spinning it with air in it,
the centerline of the tread shows almost no wobble.
Well, that's how it should be, of course.
With 7 bar pressure in the new tire, it measured about 27C wide.
The rim is a DT XR 331, so
it's not an exceptionally wide rim.
It's already wider than the so-called 25C
5000 S TR after six months of use,
but starting today I'll be monitoring how the tire durability holds up,
whether it gets wider afterwards, and
if so, to what degree.
Grand Prix 5000 S TR tubeless ready tire that had been sitting for about three weeks
lost its seal when the rim bead hook lifted,
causing the sealant to harden (→here).
After cleaning the tire and rim and adding sealant again,
I continued using it,
but today I noticed the rear wheel had a significant wobble.
There was a spot where it was jumping noticeably to the right.
However, when I put it on the truing stand,
the wheel showed almost no wobble.
The wheel in the image above is rotating.
It wasn't the rim that was wobbling—it was the tire.
This is the state of lightly touching the gauge of the truing stand
to the tire sidewall on the left side (non-drive side),
and in most phases of rotation,
there are spots that touch similarly lightly.
At the phase where it jumps to the right,
there's this much clearance.
I'm not sure if the tire sidewall casing has burst internally
and torn, stretching the sidewall,
but when I examined the removed tire,
the relevant spot on the tire sidewall was indented and pinched.
Before removing the tire, let me check how much the so-called 25C tire
has stretched after about six months of use—or rather, constant pressurization.
There was variation depending on the phase of rotation,
but the widest section was just under 26C.
This was surprising even to me,
but that wasn't the phase with the noticeable jump.
The air pressure limit was set at 7 bar (which is also the rim's limit),
and I would top it up whenever it dropped below 6 bar.
After cleaning the sealant off,
I weighed the tire.
Considering the slight traces of sealant remaining
and the fact that it was still damp right after water washing and wiping,
the actual weight is probably around 255g.
↑ The weight of the same tire when new.
I've been running it since June 30 of this year,
and in the linked article at the beginning,
I wrote something like "it's definitely going to last six months,"
but due to this unforeseen issue, it fell just short at almost six months.
After this, I was thinking of going back to using IRC's Formula Pro S-Lite
tubeless ready in 23C or 25C,
knowing that their lifespan is short,
but I have a tire already purchased for the next one,
so I'll use that first.
That tire is, as the title suggests,
the Grand Prix TT TR.
I will probably only ever use this tire once more.
It's a Continental tubular tire, and while there are multiple flagship models,
the pricing is identical across all of them—seemingly to indicate
that they're in the same class despite different intended uses.
Those were Competition, Grand Prix 4000 S II, and Tempo II—three models—
but Grand Prix 4000 S II was discontinued,
so the current flagship line is now two models.
The current MSRP for those is ¥17,727 before tax, but
this is a reverse-calculated figure derived from wanting
a tax-inclusive MSRP of ¥19,500
(strictly speaking ¥19,499.7).
When I looked up the 2013 Competition's MSRP,
it was ¥9,500 before tax with 5% consumption tax for ¥9,975 including tax.
Now, regarding this Grand Prix TT TR,
the MSRP is ¥15,455 before tax,
with a tax-inclusive MSRP of ¥17,000.
Strictly speaking that's ¥17,000.5, but
at shops selling at MSRP with POS systems that input prices
based on the pre-tax amount,
if you bought two at once, would it ring up as ¥34,001?
Who knows.
Anyway, setting that aside, there's a rubber strip
like a piece of kombu seaweed that has no tube sewn in,
just lying open toward the rim—
priced at the same level as a tubular tire.
That's hard to accept, and
considering the probably short lifespan,
it results in abnormally high running costs.
At this price point, honestly,
I'd rather spend that money plus a bit more on
a tubular tire for a tubular wheel,
so I might only use this tire once.
If the tubular option were something never relevant to me,
it might have become a piece of equipment
kept continuously in reserve as a Sunday-best dress tire—
not in regular use but maintained available.
The sticker (→here) wasn't
on the box for this tire,
but of course it was procured from
the sole Japanese distributor of Continental.
The 5000 TT TR is a new model, so
it probably hasn't been applied yet.
The measured weight of the 25C tire after removing the instruction sheet
from inside the tire package.
The tire has PP banding wrapped around it, but
that weighs barely a gram or less.
IRC's lightweight tubeless ready model S-Lite
also comes in a 23C option,
with published weights of 205g for 23C and 220g for 25C.
S-Lite tends to have measured weights slightly lighter
than the published specs, so
weight-wise, with the same width,
they're about equivalent.
Incidentally, the published weight for the 5000 TT TR is
225g for 25C and 240g for 28C, so
this time I seem to have gotten a favorable specimen weight-wise.
After mounting on the wheel and spinning it with air in it,
the centerline of the tread shows almost no wobble.
Well, that's how it should be, of course.
With 7 bar pressure in the new tire, it measured about 27C wide.
The rim is a DT XR 331, so
it's not an exceptionally wide rim.
It's already wider than the so-called 25C
5000 S TR after six months of use,
but starting today I'll be monitoring how the tire durability holds up,
whether it gets wider afterwards, and
if so, to what degree.