TPI's on road tyres and open tubulars

[cydonian74]

Some manufacturers seem to talk alot about how supple their casings are for their tyres/tubulars and open tubulars, but aside from the 'feel' and ride quality, is there any benefit to high thread per inch counts on tyres? Are they more puncture resistant or do they hold their shape better? Do they perform better at high speeds etc

I have just recently read, for example, that the new Mavic Yksion Griplink and Powerlink tyres are around 150 tpi (or was that 120tpi ) and Continental don't seem to really ever mention TPI's on their tyres so what's it all about? Is it all just marketing, surely not?

[btompkins0112]

High TPI tires are generally thiner and more flexible contributing to the "better" ride quality. Higher TPI tires are also less robust in that they wear faster and are less puncture resistant even with the increased about to threads. Higher TPI numbers are also associated with lower rolling resistance and lighter weight.

I can't speak to the voracity of the information as the general understanding of tire characteristics and rolling resistance is fluid, but I can say that higher TPI tires have a more supple casing that contributes to a less harsh ride imho.

[Estelja]

Vittoria has a decent write-up on this:
http://www.vittoria.com/tech/faq/ under "What makes a good tire".
Basically, higher tpi = more thread, less rubber to deform and absorb energy.

[two-one]

Continental Grand Prix 4000S claim to be 330tpi.

My next tires are going to be a set of 25C ones

[fdegrove]

Hi,

Continental Grand Prix 4000S claim to be 330tpi.

Not really. It depends on how you like to define (and market) the TPI numbers.
The way Conti does it is by adding the individual TPI numbers of all the layers they use in the casing. In this particular case this would mean 3 x 110 TPI = 330 TPI.

Traditionally the numbers represented the number of cotton threads in a 1" lenght of single layer casing.

You can well imagine the difference in suppleness between the two ?
Suffice it to say that anyone can easily detect the difference between say a 320 true TPI count Vitto and a summed TPI count just by holding the two tyres in your hand. It's not subtle.

IOW, one of the cases is constructed not unlike a truck tyre whereas the other is clearly designed for winning races.
It clearly shows in the Crr figures anyhow.

Marketeers and the truth, he?

Ciao,

[theremery]

Absolutely agree with Fdegrove. Do a quick google search on AFM CRR spreadsheet.......go read. See where continental lay within the scheme of things.

[Tinea Pedis]

I'm using Challenge open tubular's at present and they are an incredibly supple ride and roll very well.

However do rip up a whoooole lot faster than GP4000s that I would run back home.


At the end of the day, will come down to a question of what you value more. $$ or ride quality.

life is too short to ride crappy tyres

[OrbeaAgony]

Higher TPI tires are also less robust in that they wear faster and are less puncture resistant even with the increased about to threads.

I would argue that tire wear certainly, and puncture resistance to some degree, is more a reflection of the amount and type of rubber used for the tread, rather than the casing's TPI count. Granted, higher TPI tires tend to have thinner rubber for their thread due to their nature as a tire designed for high-end competition or the well-to-do Sunday rider.

Just some thoughts...

[bricky21]

^Higher TPI tires stretch more, and effectively make the rubber thinner when riding, so yes the supple casing plays a role in how easily the tires cut up or puncture.

[fdegrove]

Hi,

That's complete rubbish, sorry.
High TPI tyres (true TPI count) deform better over road irregularities and by extension over foreign objects on that road. Same goes for latex inner tubes inside such high TPI count tyres.

Cuts in such a tyre may have a bigger impact as most of these tyres (or tubs for that matter) are designed for races and as such come with the minimum amount of high quality compound. So that may be the reason, not the fact that they've a high TPI count.

One could say it's all horses for courses so, ultimately we all have a choice which can't be a bad thing. The trick is to chose wisely...

That said, you'd be amazed how durable and puncture resistant some of these topnotch tyres can be. Give them a try before they're all gone (as they will disappear eventually) as life is too short to ride crappy tyres anyways...

Ciao,

[roca rule]

somebody forgot to mention the fabric types like
silk vs cotton vs ...(nylon?)

[rruff]

It clearly shows in the Crr figures anyhow.

Not so much. Those crappy 110 tpi Conti casings do very well in the SuperSonics. The GP4000S does well also considering the durability.

[thisisatest]

like most people said, generally higher thread count has a better ride. tread wear is not directly linked. id say a higher tpi casing has slightly less cut resistance for a couple reasons- directly, a 100tpi ply is thicker than a 330tpi ply. the threads have to be thinner to fit that many in an inch. so an object has to cut deeper in a lower tpi casing. an indirect reason is nobody making the effort to make a smooth riding tire is going to put a stiff breaker strip under the tread. theyd go for something tough, but as flexible as possible...
generally, to make anything with a high (over 150?) thread count, it has to be tread vulcanized onto the casing, as opposed to molded in. something to do with production techniques.
i think the conti supersonics gain back some crr with not having a breaker strip of any sort and having a thin tread. possibly the casing material as well, as (its been tested somewhere) cotton, although supple, has higher energy loss (hysteresis) associated with it. dont know why. silk is best. conti uses nylon for its fast tires, saves cotton (at a higher per-ply tpi) for its cheap giro tubular...

[Courant]

It clearly shows in the Crr figures anyhow.

Not so much. Those crappy 110 tpi Conti casings do very well in the SuperSonics. The GP4000S does well also considering the durability.

Yes, but the issue with this is that the Crr tests are done at constant pressure. However, in order to get a similar "suspension" effect from e.g. a GP4000 (and thus similar levels of suspension losses on rough roads), you need to run it 10-15psi lower than e.g. an Open Corsa, and this lower pressure then contributes to higher casing losses. I ride both regularly, the GP4000 is probably the fastest/grippiest high mileage tyre out there, but Vittorias get wheeled out for races

[kgt]

exactly