New Michelin Power Cup Tubeless: GP5K S TR competitor
Moderator: robbosmans
Forum rules
The spirit of this board is to compile and organize wheels and tires related discussions.
If a new wheel tech is released, (say for example, TPU tubes, a brand new tire, or a new rim standard), feel free to start the discussion in the popular "Road". Your topic will eventually be moved here!
The spirit of this board is to compile and organize wheels and tires related discussions.
If a new wheel tech is released, (say for example, TPU tubes, a brand new tire, or a new rim standard), feel free to start the discussion in the popular "Road". Your topic will eventually be moved here!
Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓ Broad Selection ✓ Worldwide Delivery ✓
www.starbike.com
Indeed, more relax than what schwable still has on their website. Not long ago seems that Continental customer services was also using an outdated table.Hexsense wrote:Hmm, according to this ETRTO spec.
25mm tire on 23mm rim should still be okay. 28mm tire on 25mm rim too.
-
- Posts: 180
- Joined: Fri Mar 15, 2019 4:19 am
On my Lightbicycle AR56 rear wheel, 30mm external, 23mm internal, the Powercup 28mm tires measure 30.2mm. Not as bad as I was expecting... It's mounted for about a month and has about 250 miles on it. I just got a 25mm powercup for the front wheel.
2018 Fuji Transonic 2.5 rim (6.90kg)
2020 ICAN AC-388 cyclocross bike (8.41kg)
2021 Trek Emonda SLR RSL H1 rim (5.65kg)
1980s vintage ALAN Super Record (haven't weighed it)
2020 ICAN AC-388 cyclocross bike (8.41kg)
2021 Trek Emonda SLR RSL H1 rim (5.65kg)
1980s vintage ALAN Super Record (haven't weighed it)
Strange enough. If Michelin truely sticks to the latest ETRTO, their tire shouldn't be so wide. A tire of nominal width 25c should represent roughly the real width on a 19c rim, but a 25c power cup tlr is ~28 mm on a 19c rim.
I am not familiar with the entire norm but it starts at 15c, it looks like the labelling is matching this.alanyu wrote:Strange enough. If Michelin truely sticks to the latest ETRTO, their tire shouldn't be so wide. A tire of nominal width 25c should represent roughly the real width on a 19c rim, but a 25c power cup tlr is ~28 mm on a 19c rim.
Another conflict besides the tire width is the label on the TLR sidewall. It doesn't agree with the latest ETRTO as mentioned several pages before. The max pressure (25c TLR) is labelled as 7(6) bar on 17(19) c rim, and the suggestion stops at 19c rim. A esay calculation gets 5 bar max on 21c rim. However, the min pressure is labelled as 5 bar for either width, resulting in no room for >21c rim.C36 wrote: ↑Thu Aug 11, 2022 7:19 pmI am not familiar with the entire norm but it starts at 15c, it looks like the labelling is matching this.alanyu wrote:Strange enough. If Michelin truely sticks to the latest ETRTO, their tire shouldn't be so wide. A tire of nominal width 25c should represent roughly the real width on a 19c rim, but a 25c power cup tlr is ~28 mm on a 19c rim.
What is your "simple calculation"? You assume linearity between max. presure and internal rim width?alanyu wrote: ↑Thu Aug 11, 2022 8:04 pmAnother conflict besides the tire width is the label on the TLR sidewall. It doesn't agree with the latest ETRTO as mentioned several pages before. The max pressure (25c TLR) is labelled as 7(6) bar on 17(19) c rim, and the suggestion stops at 19c rim. A esay calculation gets 5 bar max on 21c rim. However, the min pressure is labelled as 5 bar for either width, resulting in no room for >21c rim.C36 wrote: ↑Thu Aug 11, 2022 7:19 pmI am not familiar with the entire norm but it starts at 15c, it looks like the labelling is matching this.alanyu wrote:Strange enough. If Michelin truely sticks to the latest ETRTO, their tire shouldn't be so wide. A tire of nominal width 25c should represent roughly the real width on a 19c rim, but a 25c power cup tlr is ~28 mm on a 19c rim.
Litespeed Gravel Ultimate : https://tinyurl.com/zvxxy8zk
Wilier “Cento Ramato“ : https://tinyurl.com/29vs8vre
#RETIRED# Lynskey “the Do-it-all Helix” :https://tinyurl.com/bdmb5y24
Wilier “Cento Ramato“ : https://tinyurl.com/29vs8vre
#RETIRED# Lynskey “the Do-it-all Helix” :https://tinyurl.com/bdmb5y24
-
- Posts: 12456
- Joined: Mon Jul 24, 2017 12:02 pm
So, are you saying that enve, zipp, giant and maybe others when recommending a 28c for a 25id or a 25c for a 23id are following etrto specs?!?! OMG the shock
That I did not expect. I was honestly convinced that these big name brands were just following some misguided measures and tests that some marketing guy came up when going to take a dump.
To be fair, some of those big wheel companies actually recommend those combo before the new ETRTO standard is final. Some start to promote the combo while it's in the draft state.
While some promote way before that. They found from their tests that wide rim+ narrower casing tire works better. And that could influence ETRTO to consider these combo as well. And indeed, they found it safe. That's why ETRTO approve it.
PS. HED promote 23mm tire on 21mm IW rim half decade ago. Cannondale follow suite with Systemsix having 23mm tire on 21mm IW rim from the factory. Yet, updated ETRTO don't approve 23mm tire on 21mm IW rim combo.
While some promote way before that. They found from their tests that wide rim+ narrower casing tire works better. And that could influence ETRTO to consider these combo as well. And indeed, they found it safe. That's why ETRTO approve it.
PS. HED promote 23mm tire on 21mm IW rim half decade ago. Cannondale follow suite with Systemsix having 23mm tire on 21mm IW rim from the factory. Yet, updated ETRTO don't approve 23mm tire on 21mm IW rim combo.
-
- Posts: 12456
- Joined: Mon Jul 24, 2017 12:02 pm
And some tire companies aren’t following the guidelines. Goodyear advises to only use their 25mm tires up to 22C and 28mm tires up to 24C.
Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓ Broad Selection ✓ Worldwide Delivery ✓
www.starbike.com
And we could add that the labelled size rules are clear as mud. Most brands have their tire width using a single rim reference. Vittoria has a different rim width reference for different tire size… that may be closer to what happen in real life and limit surprises.
Now, 24mm tires are labelled for 17c but 26mm tires labelled for 19c. So what happen on a 24mm tire on a 19c rim? And a 26mm on a 17c? Would they both measure around 25mm?
Cv
Now, 24mm tires are labelled for 17c but 26mm tires labelled for 19c. So what happen on a 24mm tire on a 19c rim? And a 26mm on a 17c? Would they both measure around 25mm?
Cv
Last edited by C36 on Fri Aug 12, 2022 6:51 pm, edited 1 time in total.