New Michelin Power Cup Tubeless: GP5K S TR competitor

[Jaisen]

using labeled width for any general safety guidelines is stupid when there are no standards for actually determining how tyres should be labeled

ISO recommends for Road tires that the width as measured should be within +/-2 mm of the tire's labeled width. That's pretty much the design tolerance for the tire.

[lukaszzsch]

Most likely Michelin didn’t follow that recommendation


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[Matte86]

using labeled width for any general safety guidelines is stupid when there are no standards for actually determining how tyres should be labeled

I agree… but then besides personal preferences and/or the +4mm ISO rule for hookless What people should follow? It’s all over the places
Tyre manufacturers develop and release in 2024 products based on 19 IW while some rims manufacturers pushes bigger and bigger IWs

[naavt]

For whatever it's worth, I've used these tires in tubeless form, 25s on 303s for several months with no issues at all, with plenty fast descents since I live in a very hilly area.

Nonetheless, I've swapped wheels even before the latest "tubeless disasters", mainly because I've decided to return to tubes and had my own doubts about hookless tech at the time.

I'm now running powercups 25 clinchers on Bora wheels

[BigBoyND]

using labeled width for any general safety guidelines is stupid when there are no standards for actually determining how tyres should be labeled

ISO recommends for Road tires that the width as measured should be within +/-2 mm of the tire's labeled width. That's pretty much the design tolerance for the tire.

Does ISO prescribe an IW? If not, then this is still meaningless.

[Jaisen]

using labeled width for any general safety guidelines is stupid when there are no standards for actually determining how tyres should be labeled

ISO recommends for Road tires that the width as measured should be within +/-2 mm of the tire's labeled width. That's pretty much the design tolerance for the tire.

Does ISO prescribe an IW? If not, then this is still meaningless.

Why would it be meaningless? Suppose you start with a 700x25 labeled tire that was designed around a 19 mm IW rim. You now install it on a 21 mm IW rim and it measures 27mm, all is well. Now you install it on a 23 mm IW rim and it blows out to 28mm. That is out of ISO spec.

Next you take a 700x25 tire designed around a 21mm rim. It might be fine all the way up to a 25mm IW rim before it gets out of spec (not that you would ever want to run a 700x25 on a 25 IW rim, it is only to illustrate the point). Similarly in the other direction too, it might be ok until you hit 17mm IW or lower.

[BigBoyND]

Exactly. ISO needs to provide the IW otherwise "25mm" would be very different if it's designed around 17mm or 22mm rims.

[C36]

From the very good EC article on the topic



25-28 labeled tires should be designed around a 19mm IW rim (and before we say it’s too narrow, it is rather at the mid point of rims IW compatible with those tire sizes)

So we do have a reference, the mystery is more on the why all XX mm tires do not measure XX when installed on their reference rim.

[TobinHatesYou]

As a reminder, Jarno's 25mm Power Cup TLR measured nominal width +2.7mm at design rim width -1.2mm. Just way, way off

[BigBoyND]

I wish they were even bigger! Haha. I'm enjoying my Tufo Prima at the moment (even more oversized) but the Power Cup with tan sidewalls in a bigger size than 28mm would be something I'd like to try.

[alanyu]

I wish they were even bigger! Haha. I'm enjoying my Tufo Prima at the moment (even more oversized) but the Power Cup with tan sidewalls in a bigger size than 28mm would be something I'd like to try.

Power Cup should have a much wider tread like Comtura, not a 25C labelled tyre blown to others 28C width but with only 23C tread!!

[BigBoyND]

I don't mind it at all. Never had an issue with it. It's close to the Corsa Speed, Fusion 5 G, Tangente Speed, Eagle F1 SS R.... whether it's 35% instead of 37% coverage, isn't a deal breaker.

[Feddesman]

Roval clxII 21 internal with 28 power cup tubeless is ok? No danger on riding on the sidewalls?

Coming back from retirement just to spread a word on safety regarding these tyres.

I've had some very bad experiences with these.

One keen (very handy) crit rider has had some nasty crashes on full tilt on these. Described as sliding out on ice when at max lean angles (essentially cornering on the sidewalls). 28mm Classics on Roval Rapide CLX.
He is now on 28mm Corsa Pros and loving life.

Also had a few customers in where the tyre tread has completely detached from the casing, and large slits / gaps in the tyre.

Even after having good personal experiences with these tyres (for around 1,000km), from what I've seen, I would not recommend these at all.

[lukaszzsch]

I use 25c Michelins on 21mm bontragers, keep in mind that their WAM exceed 30 mm., I suppose 28mm a will be even wider.

Fortunately the problem you mentioned doesn’t exist, zero punctures over 1,5 season.


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[Talrand]

My pair of TLR 25s just arrived and after a test fitting with tubes at 5 bar on a 18mm IW rim they measure just under 27mm. Did Michelin get their sizing in order or could there be so much variance between batches? Weights were 263g and 270g.