A simple slide guide to tubeless and hookless

[makoti]

Originally Posted by benb

He is talking about hookless.

But for me the 72psi limit for pavement riding is just too limiting.

Are you sure? It doesn't specify hookless in the first part, though it does as #3

[benb]

You're right, he's mixing them up.

I think the "never go about 72.5psi" is intended for hookless though, but maybe an oversimplification to provide safety?

I have no doubt I could figure this out and get myself on a setup that would work. But it would cost me a ton of money and I am extremely skeptical it would actually improve riding at all for me. The only possible benefit would be access to more aero wheels.

[FastCanon]

I had a 2mm gash a couple of weeks ago. I thought it wasn't sealing when I pumped it up so I rode for several blocks before needing to pump up again. The second time I pumped up the tire, it seemed the puncture had sealed. My tire hasn't lost air since but I did need to wash my bike and added more sealant.

I should have rotated so the gash be at the bottom of the wheel to let sealant seal before pumping. Rain and urgency to come home before certain time makes you skip steps.

[MikeD]

Originally Posted by benb

You're right, he's mixing them up.

I think the "never go about 72.5psi" is intended for hookless though, but maybe an oversimplification to provide safety?

I have no doubt I could figure this out and get myself on a setup that would work. But it would cost me a ton of money and I am extremely skeptical it would actually improve riding at all for me. The only possible benefit would be access to more aero wheels.

According to the newest ETRTO standard, 72.5 psi only applies to tire width of 25-29mm. The wider you go, the less the max pressure.

[Mark McM]

Originally Posted by MikeD

According to the newest ETRTO standard, 72.5 psi only applies to tire width of 25-29mm. The wider you go, the less the max pressure.

Yes, this is an important point. And this type of confusion is part of the argument against hookless - there are many more factors to consider, and a lot of confusion in the marketplace regarding proper practices for hookless rim, and when combined with lower safety tolerances of hookless makes it easier to get into trouble if you don't know what you are doing.

The original charts say that the maximum pressure you should ever use in hookless tires is 72.5 psi, and that you shouldn't exceed the maximum pressure printed on the tire or rim - but this is incorrect. Firstly, as MikeD pointed out, the maximum pressure for hookless rims varies with tire width. Here's the maximum pressure chart from the article on the Escape Collective:



For example the maximum pressure for a 35mm tire is 400 Kpa = 58 psi.

Secondly, many tubeless tires will have a higher maximum pressure when mounted on hooked rims than when mounted on hookless rims. But the sidewall of the tire may only specify the absolute maximum pressure (i.e the maximum for hooked rims), rather than the maximum pressure for hookless rims. For example, a 700x30c tubeless tire may have "maximum pressure 75 psi" printed on the sidewall, which may be perfectly fine on a 19mm hooked rim, but is 10 psi (15%) above the 65 psi maximum for this size tire on a hookless rim. Even if this tire was inflated to the maximum 72.5 psi printed on the rim, then it would still be 2% above the blow-off pressure tolerance - and if it was inflated with a pump whose pressure gauge reported lower than actual (and many bicycle pressure gauges are only good to +/- 10%), then this tire could be even further above the maximum safe pressure.

[fa63]

Personally, I wouldn't stick my neck out and advocate for hookless, even with all the caveats. I would instead list the pros and cons of both hooked and hookless so the end user can make an informed decision. But that is just me.

[fa63]

I also just noticed that Zipp have modified their online tire pressure calculator when hookless is selected, so that when it comes up with a pressure that exceeds the rim pressure rating, it throws up an error message instead simply saying use the maximum pressure. Not sure when that change was made, but I remember it not being like that when I last used it (for example, it would just say 72.5 psi for 28 mm tires on hookless rims even if you put a 250-lbs rider in there).

[Dave]

FWIW, a 250 pound rider on 23mm IW rims and 35mm tires only needs 58psi, according to Zipp. That's well under the ETRTO maximum. Using 25mm IW drops another 2psi off.

I'd follow the recommendations on the tire. My 30mm Pirelli P-Zero road TLR tires say 5 bar maximum hookless, but 6 bar hooked.

[Mark McM]

Originally Posted by Dave

FWIW, a 250 pound rider on 23mm IW rims and 35mm tires only needs 58psi, according to Zipp. That's well under the ETRTO maximum.

That's actually the ISO maximum for that tire width on hookless* rims (see table above). Interestingly, Zipp recommends 62 psi for the same rider, tire and inner rim width, if the rims have hooks.

*There was an error in the original post that has now been corrected - originally it incorrectly said "That's actually the ISO maximum for that tire on hooked rims."

[Baron Blubba]

Sigh, I should have known this would cause another tubeless spitstorm.

Let's lighten the mood with a little irony. Today, a half our after making this post, I went for a ride on the only non-tubeless (I think they called that tubed back in the anteditubelesseluvian days) bike I own.
Less than an hour after that...this happened...
[IMG]Untitled by Michael Lock, on Flickr[/IMG]
Annoying, but couldn't help but laugh. This is the first flat I've had in like two years, riding 20+ hours a week. Thank goodness I still remember how to fix these things.
Tangential product review: The Fumpa Pump Nano mini compressor is really good. So small and light I don't feel it in my pocket, and it inflated my tire in no time...flat? Never bothering with co2 or mini hand pumps again, cross my bosom.

Anyway.

- To the gentleman who had a momentary lapse of gentleness and accused me of advocating for tubeless or hookless because I sell it: That is quite a cynical and slanderous indictment of my character. I sell things that I advocate, not other way around. If I really wanted to make money, I'd tell all of my customers how awful and unsafe hookless is, and, since many performance bikes come with hookless wheels, make an add-on hooked-rim sale. Ka-ching.

- To the same momentarily lapsed gentleman, who now posits that tubeless is thousands of dollars that don't need to be spent. Correct, the money doesn't need to be spent. But insinuating that the price is any higher than a regular wheelset is misleading. A tubeless wheel is no more expensive than an equivalent clincher. Further, you could get a tubeless wheelset for under $500 if you wanted.
But I understand that you don't feel the need to change what's working for you. I've said it before and I'll say it again: Bikes keep getting better and better, and the improvements between iterations are often substantial --I'm not talking just 'aero/stiffness/weight/compliance', I'm talking the overall feel of these bikes.
And yet, when I ride my 30+ year old Trek 2300, or an $800 aluminum Claris equipped road bike, I think 'dang, bikes don't really *need* to be better than this in order for me to have a great time.'
Still, when I get on a great modern bike, I think 'Dang, I'm lucky to be alive and loving bikes at a time when bikes are so amazingly good.'

- To the fella who suggested that I have obligations to companies which caused me to word certain things certain ways: I have no obligations to anyone. I wrote this admittedly imperfect 'document' for the educational benefit of my customers and whoever else finds it floating around FB or IG. If a certain point was applicable to hookless, I usually erred on the side safety and did not distinguish between hookless and tubeless. Still, I like your idea of asterisks, and will incorporate that into the next edition.

- As far as 75 psi or less being limiting, I think that's only true if one is heavy, say 220+ lbs, and likes the feel of a 25mm tire. That simply isn't possible with tubeless --you'd have to go to (and I'm not checking my math or science on this, I'm sorry) somewhere around 32mm. Otherwise, I don't get what is meant by 'limiting.'

- I used the 72.5 psi number as the maximum just to err on the side of safety. Also, anything above 75-80 psi and I've noticed that the sealant becomes less effective, so I was considering not only rim/tire safety but also the efficacy of the entire tubeless set up.

- I want to reiterate that I created this not as a sales tool, goodness knows I don't need to resort to this to sell bikes. I made this because the other spitstorm of a hookless thread that's currently hanging out on the first couple of pages of this forum made me realize how important tubeless/hookless safety education is. I thought something like this would be useful. And since the purpose was *safety*, I tended to err on the side of safety with my advice, within reason.

- I think that tubeless is a relatively young technology for the road. As such, lots of people who are having bad experiences are using it incorrectly. Running pressures too high, not being prepared with a tubeless repair kit on the road. In my opinion, it's not perfect, but I think it's better than running tubes. Never mind the performance metrics benefits (I don't care about that stuff), I just think it feels a lot better than riding tubed, and yes, even better than riding Tubolito or Aerothans, which I use in my Ritchey and which are excellent. And the fact that I have not had a ride-ending puncture in years, and only had to stop a couple of times in all those years to plug the hole or let the sealant do its job, is very valuable to me.

- I started riding tubeless around 2015-16. I noticed a difference in ride quality right away, to the point where I didn't want to get off my bike (what else is new, but you know what I mean) that day because that novel feeling felt so darn good. Yes, tubes work and are fine and reliable; but I genuinely prefer the substantially improved (to my body at least!) feeling of tubeless, and so that's what I use, and that's what I recommend to folks rely on me to help them have the best bike riding experience possible.

Thanks to everyone for reading and for making some valuable suggestions. I am going to revamp this to be simpler, more reader friendly, and less ambiguous on the differences between hooked and hookless tubeless, within reason. I won't be updating this every time some wheel manufacturer or cycling organization moves the goalposts a couple of inches.

[jimoots]

The simple slide guide turned out to be not so simple.

[fa63]

Because there is no way to make that happen as things stand

I guess one could just say "follow all manufacturer recommendations" and leave it at that, which would get us back to exactly where we are today

[NHAero]

Originally Posted by Mark McM

That's actually the ISO maximum for that tire width on hooked rims (see table above). Interestingly, Zipp recommends 62 psi for the same rider, tire and inner rim width, if the rims have hooks.

Isn't that table for straight sided (aka hookless) rims?

[RoosterCogset]

Originally Posted by Mark McM

That's actually the ISO maximum for that tire width on hooked rims (see table above). Interestingly, Zipp recommends 62 psi for the same rider, tire and inner rim width, if the rims have hooks.

Whatever happened to charts like this? From a couple years ago, but there seemed to be some sense in there being a 3-factor guide for Max inflation (rim width +tire width + rim type), . FYI, TSS = Hooklesss.

[EB]

I remember in 2018 I rode the Tahoe Trail 100 XC race at Northstar, and day before we did a pre-ride with Levi Leipheimer himself to acquaint ourselves with the start and finish of the track.

We stopped for a bit and Levi led a long lively discussion of tire pressure. People were comparing and debating 21 psi, 22 psi, 23, 24 psi and so on.

Then one cranky gentleman "explains" that he's been running his mountain bike tires for years at 60 psi AND EVERYTHING IS JUST FINE, THANK YOU VERY MUCH <oldmanyellsatcloud.gif>.

Just goes to show you that operator error even with mature technology is inevitable, and sometimes, insisted upon.