EdIsMe

I might be out of my mind but it's a bit rainy today and that got me to thinking...

What do you think the outcome of using tubular mastik on the bead of a tubeless or non-tubeless tire on a tubeless rim would be?

I'm thinking that the bead of the tire would adhere to the clincher hook of the rim more securely with the glue and would also prevent leaks as it is latex based.

This may be a possible solution to using non-tubeless tires in tubeless setups?

Also posted in Road Cycling.

Thanks for your replies!

well biked

Keep in mind, with road tubeless it's the road tubeless TIRE, not the rim, that make a high-pressure road tubeless setup possible. You can set up road tubeless with most road clincher rims ("tubeless-ready" or not), as long as you use one of the handful of road tubeless tires on the market. Gluing the tire to the rim? Not necessary, and not recommended. And please don't go and try a standard road tire at high pressure, set up tubeless, on ANY rim, with glue, without glue, etc. That's a recipe for disaster.

FWIW, I much prefer Hutchinson's road tubeless tire offerings, I have many thousands of miles on them with zero problems of any kind. Most recently, I've purchased a road bike with clearance for wider tires, and I'm running the Hutchinson Sector 28's road tubeless tires with Stan's Notubes Alpha road rims. Pressures in the 80's, awesome ride quality. We've also had great luck with all of the Hutchinson road tubeless models in both 23mm and 25's.

I will say this about tubeless setups and glue: In the early days of UST tubeless on mountain bikes, a lot of people were frustrated with the tires not holding air. I saw tires that were glued to rims in those days, in an attempt to keep the tires from leaking at the bead. Stan's Notubes sealant eventually became the solution to that, and I haven't seen a tubeless tire of any kind glued to the rim in many years. That's not to say it's not being done, but it's not common.

I've run a lot of tubeless setups on my own bikes, including road tubeless starting a couple of years ago, and I've never seen any need whatsoever for gluing the tire to the rim. We set up tubeless tires, both road and mountain, on customers' bikes at our shop all the time.....no need for glue.

FBinNY 

One possible issue with using tires not intended for use tubeless might be porosity. Tubes are made of Butyl and are relatively good in terms of porosity to air. Tubeless tires should likewise have a butyl lining. OTOH tires not made for use tubeless would lack this lining and the natural bleed rate may be unacceptably high.

As I said, this is a possible issue, the only way to confirm is to try it.

well biked

Standard mountain bike tires (i.e. not designed for tubeless) have been used for many years tubeless, with the use of liquid sealant such as Stan's Notubes. The sealant takes care of any problematic porosity in the tires, and helps to seal the bead, spoke holes, etc. One of the key advantages to mountain tubeless is the extreme low pressure you can use without pinch flats. It's also the low pressures that make this possible in the first place.....the stress on the tire's bead is minimized by the low pressure, so many tires not really designed for tubeless applications work just fine.

Road tubeless is a completely different animal because of the much higher pressures used with road tires. Even at the reduced pressures of road tubeless and narrow tires, you're talking about pressures in the 80's, 90's, 100 psi, etc. They design the beads of road tubeless tires especially for this (tubeless at high pressure).

No, I don't know of anyone who's glued a standard road tire to a rim and tried to run it tubeless....nor do I want to . There's no way I would recommend it, the tire's bead is simply not designed to do that. It has nothing to do with the porosity of the tire, sealant would take care of that. The high pressures of road tire applications, run tubeless, should be left to road tubeless tires that are designed for it. There's a safety issue here that shouldn't be taken lightly.

Yes, I've blown many mountain tubeless tires off the rim during setup, which would have been no problem at all with an inner tube at the same pressure. Tubeless can be a weird "science."

Bottom line: only use road tubeless tires for road tubeless.

FBinNY 

I was talking about molecular porosity, which I doubt Stans would address, However that's not a major issue with large section, low pressure mtn tires. However it could become an issue on road tires which have thinner walls, a high surface to volume ratio, and high operating pressure. These are the three witches of tire pressure loss, and if the lack of a butyl or other barrier liner is an issue, it'll be a serious issue.

Again, not saying it is, but it could be, especially with tires with "open" walls.

As for using glue, or other issus, I simply don't know --- I still ride tubulars.

well biked

Okay, molecular porosity.....what I'm getting at is this: let's don't tempt this person to try setting up a standard clincher road tire without an inner tube, with or without tubular glue. The psi is too high with road applications for tires that aren't designed for this. It would be dangerous, simple as that. I don't know with 100% certainty that it wouldn't work, but there would be only one way to truly find out: ride it extensively. Again, that would be dangerous. There are already tires on the market that ARE designed for this. And again, to the OP: you don't need tubular glue to make it work just fine.

FBinNY 

I'm strictly agnostic on the issue, but can't see that tire retention would be affected in any by the presence or lack of an inner tube. Th tube is simply an air bladder, and provides no structure at all. Tires either have a bead and/or hook design adequate to holding against the pressure, or they don't.

In fact, the higher operating pressure of road tires vs. downhill mtn tires can only work to help the seal.

As far as the OP is concerned, he has to try his experiments on his own. I be more concerned with the safety of anybody that makes decisions based on a consensus here on BF.

well biked

It does. Believe me or not, but it does.

FBinNY 

As I said, I'm strictly agnostic, and ride tubulars on the road.

OTOH- how many times here on BF have we explained to newbies that their "tube" blowout had nothing to do with the tube, and it was the tire alone that counted.

I suspect that one issue that separates tubeless tires from tube tires is a soft "sealable" layer at the bead line to ensure seal integrity, but that's something the OP can discover for himself.

If there's concern over safety, he can try the rear wheel only, and treat it to harsh road conditions, while avoiding any high speed descents until it proves itself one way or the other.

well biked

Copy and paste from Stan's Notubes site, regarding road tubeless:

"Please note, unlike with mountain bike conversions, specific Road Tubeless tires are required for conversion. They have been designed with a folding tire bead that will not stretch and cause catastrophic blowouts. Road Tubeless tires must be used....."

And this from the company that revoltutionized mountain tubeless early on with their tubeless conversion kits for low pressure mountain bike applications using standard mountain bike rims and standard mountain bike tires. If a standard road tire could safely be used tubeless at road pressures, I believe Stan's Notubes would be the first to say so. But again, it's a completely different animal than mountain tubeless because of the huge difference in psi for the two applications. Road tubeless tires have specially designed beads to keep them from blowing off the rim at road pressures when used without an inner tube.

FBinNY 

So they say, and I have no basis to dispute that. OTOH, given how much trouble some folks have mounting certain tires, I can't see blowoff being an issue.

So IF the OP decides to try for himself, he should choose his tires carefully, conduct a controlled experiment and proceed with caution.

well biked

Wow.

And it's not like there aren't a growing number of road tubeless tires hitting the market.

FBinNY 

I don't see why you're so worked up over this.

The OP asked and I offered a reason why it wouldn't work to his advantage, you offered a different one.

But in the end, the OP has to make his own decision. I have no idea why he wants to try this or what he expects to gain. I'm only suggesting that IF he decides to try that he does it in the safest possible way.

EdIsMe

I feel like we're getting a bit off topic, so I quickly borrowed this picture from google and drew some pretty red arrows to symbolize air pressure.



The left image shows a standard setup on a standard rim. The right image shows a tubeless setup on a tubeless rim. To clarify, the setup I would like to refer to would be a tubeless setup on a tubeless rim. As you can see, the tubeless rim does infact alter the dimensions of what we're dealing with.

The reason why tubeless tires blow off rims and tubes don't is because of air pressure. Air pushes on the inside of the tire in all directions. In the case of the tube, the air pushing the tube casing downward, also pushing the tire bead downward and into the clincher hooks. It is the tube casing that holds the bead in place. Tubeless tires do not have a tube to keep the bead seated in place and therefore run the risk of coming unhooked and blowing off the rim. To prevent this, tubeless specific tires have a much more robust bead that will not deform or stretch in order for them to remain seated.

Believe me, I am aware of the dangers of messing with this and this is why I presented the question to the forums.

The reasoning behind the tubular glue should be obvious. Tubular glue is typically used to combat the lateral forces against the tire being pushed off the rim. This scenario is very similar to what's going on with the tire bead and the rim. Also, particularly in mountain bike setups, the glue would prevent "burping" of the tires, or the momentary loss of air from the bead separating from the rim.

Now to mention some things that I feel have been grossly overlooked:
1. Steel bead. A tire, i.e. Continental Gatorskin Wirebead, with a steel wire bead would be just as or more rigid than a carbon tubeless tire. The steel bead will not deform or stretch, and ignoring the significant weight penalty, is much less expensive than tubeless options.
2. Carbon/Kevlar folding tires. Allowing a high-quality folding tire to rest and assume a round shape will promote a bead that is not prone to deformation. We know this to be true, as these tires, when installed properly, will not roll off a rim in the event of a flat. In this event, presumably, the airless tube will no longer be applying pressure to the tire bead and is not responsible for its staying in place.
3. Tubular tires have a thicker bead that is more square shaped than round like standard clinchers. Is it possible that tubular glue could increase the bond between the tire bead and the hook of the rim?

Theoretically, a steel beaded tire or a high quality carbon/kevlar folding tire that's been properly shaped could be glued onto a rim quite reliably, especially in the event of a tubeless rim that will minimize the allowance of tire bead movement after mounting. The concern for cleaning the rims afterward is virtually moot, as this would be no more or less difficult than cleaning standard tubulars.

:

FBinNY 

Look, this is your thing so do what you will. I don't have a dog in the fight.

However, let's clear up a fallacy in your reasoning.

There is no (nada, nichts, niente, zilch) difference in the forces air exerts on a tire through a tube or or directly (tubeless). The tube has no mechanical strength to speak of and cannot add or subtract anything. The difference between having a tube in a tire or not is about the same as being punched in the face through a sheet of Saran Wrap, and being punched in the face.

There may be differences in the shape of the rim which call for tires made to fit more precisely, but the differences don't relate to issues of bead strength or the forces acting on and in the tire.

well biked

The image of the tubeless rim is either a Stan's BST or very similar. With road tubeless, which is what we're talking about, the advantage to that profile is that it makes the tire have a rounder shape and higher volume when mounted. But such a profile is by no means necessary to successfully mount a road tubeless tire (not sure if that's what you're implying). A "conversion kit" contains nothing more than road tubeless tires, valve stems, liquid sealant, and plastic highly adhesive rim tape that does a great job of sealing the spoke holes. That's it. You can run road tubeless successfully and safely with just those conversion items with standard rims. As I said in the first sentence above, the key with road tubeless isn't the rims, it's the tires.

You're right about glue on mountain tubeless tires, it can be effective in keeping the tires air tight. As I said earlier, I saw that from time to time in the early days of UST. Once it was well known that liquid latex sealants accomplished pretty much the same thing and also provided great puncture protection, I never saw a glued tubeless mountain bike tire again.

Just curious: have you ever ridden tubeless road tires? Generally speaking, I find them easier to set up than mountain tubeless, and very trouble free. Just trying to understand the reasoning for the glue idea with road tubeless.

Kimmo

I don't care who the company is; I know marketing bullsh*t when I see it. Kevlar or steel beads are both just fine for pressures up to at least 160psi, IME (being lazy and skipping the talc, I've found most stubborn tyres will seat if you temporarily overinflate them, which I've found to be harmless). And then we have everybody going, ooh catastrophe in the offing, bah. How often is a flat catastrophic, no matter how sudden? You'd have to be pretty damn unlucky (depending how often you fly down hills in the wet)... and if you just try it on the rear as FB advises, it's almost impossible to imagine a catastrophic scenario.

I'm with FB - if there's a reason it's a bad idea, it's down to porosity and/or the tyre shape and surface at the bead; many standard clinchers would require a coat of glue (or at least goo) over the bare fabric you get there on tyres like Contis and stuff. I really wouldn't be surprised if this could be made to work, with a bit of experimentation.

well biked

You guys who are saying an inner tube/tubeless makes no difference in whether a tire would blow off the rim at a certain pressure: how many times have you set up a mountain bike tire tubeless? If you have much experience with this at all, you will learn that you have to be very careful with the pressure during setup or you will have a latex explosion on your hands. Not a huge deal in shop setting, but it will definitely make an impression on you.

I edited this because I was guilty of maybe turning this thread into a pissing contest, and I really don't want to do that.

Happy New Year everyone.

fietsbob

You are applying a glue , why not just take the moments of Prep Time and use a proper patch?

and use that Glue..?

you then wont have to re do the patch or replace the tube, which would be likely with the proposed Kludge.

now, for a pretty Fat tire operated at a Low pressure , like on Snow, a gluing of 1 bead ,

resists the tire creeping around the rim and carrying the tube with it and shearing off the Stem ..


BTW a Tubular tire mounting is several layers of glue and, is at least a 1/2"_ 12mm,
wide , around the whole rim surface.


By the roadie double post, OP was seeming to think about skinny high pressure tires ,
there that issue is not there , as long as you keep your PSI Up.

Looigi

Something to ponder: With a tube, the interface between the tire's bead and rim is connected only to atmospheric pressure. Without a tube, the interface sees atmospheric pressure at the outside edge of the bead and tire pressure at the inside edge of bead. If the tire pressure gets between the tire bead and rim, there's nothing pressing it against the rim. A tube would prevent this from happening. So...based on these "imaginings", I would postulate that a tube does improve the robustness of the bead to rim seal.

mconlonx

I'd not do it for any one of a number of reasons.

1) Mainly, tubless tire/rim combos can be an absolute beeotch to get mounted in the first place and tossing messy, sticky mastic into the equation just doesn't seem smart.
2) You are dealing with liquid sealer and generally speaking, adhesives don't play nice with wet surfaces and moisture.
3) If you do glue a tubeless tire to a tubeless rim, take it off yourself, or warn a mechanic what you did and don't be shocked if there's some surcharge for swapping out your tire.

FBinNY 

It's something to think about, but here's more on the idea.

First of all if this is how things worked, mtb tubeless tires wouldn't work either, especially since they work at lower pressures. But it also calls for air going someplace it's now excluded and pushing back against the bead.

If you've ever used a pump with a cup shaped leather piston you see the principle at work. The air inside the piston pushes the cup against the cylinder wall making a seal that makes the pump functional. Note that this is a running seal, yet doesn't leak or fail.

Assuming the tire is capable of making a decent seal, there's no difference between using or not using a tube.

EdIsMe

@well biked Thanks for not making this a pissing match.

This is no more than a pondering and possibly a pending experiment.

To clear up a few things:

We are talking about tubeless setups on tubeless rims. The reason for this distinction, is tubeless rims offer less space between the wheel bed and the clincher hook (as shown in the picture). I realize this is not necessary to have a successful tubeless setup, but in the case of a non-tubeless tire it may be a crucial component.
Also, the sole function of the tubular glue would be to mate a non-tubeless tire to a tubeless rim by applying glue to both the sidewall of the tire (on the clincher bead) and to the inner sidewall of the rim. As anyone that has actually dealt with tubulars should know, applying or cleaning mastik off a rim really isn't as awful as everyone seems to make it out to be.
@fietsbob mentioned the difference in surface area that the glue will be applied to. While recognizing this as a significant truth, I wonder how much that will come into play for this application.
@mconlonx brought up the issue of liquid sealant vs. dry adhesive. I do not know for certain whether this point is valid or not. As it has been previously brought up, using mastik on mtb tubeless was once a common practice.

So to elaborate: The primary focus for this discussion is the mounting of a non-tubeless tire on a tubeless rim in a tubeless setup using sealant and/or mastik.

Happy new year everyone!

Kimmo

Lolwut... ever cleaned a bong? I'd rather do that.

Unless maybe here's the thing - the glue's improved in the 20 years since I and most others had anything to do with tubulars.

FBinNY 

Cleaning tubular glue is only a problem to those neat freaks that think you have to clean off old glue. The reality is that old glue is the best base for new glue, so not only isn't cleaning necessary, it's counterproductive.

I hate riding on new rims, and it takes about 2 tire replacements to get a nice contoured glue base. The only time I clean glue is if there are some beads of excess at the rim's edge, and that's done in a minute or so using a paint scraper.