Dried sealant? What the fuck kind of sealant fully dries inside of a tubeless tire?
Disclaimer, this story comes from automotive tires with Fix-A-Flat, but still…
We just replaced a Fix-A-Flat tire last week on an old Hyundai, and the chemical had been in there upwards of 6 months or so. There was still more than a pint of excess liquid chemical in the tire.
Like hell, dude could have used a small can of the stuff meant for lawnmower tires, then topped it off with an air compressor, and not had over a pint of liquid sealant sloshing around in his tires.
So, if sealant for tubeless bicycle tires ends up drying up sealant, well phuck, either they didn’t sell you enough, or they’re ripping you off, probably both.
The only reason my friend had to have his Hyundai tire replaced was because of an alignment issue, which has since been fixed. But still, I coulda scooped the excess Fix-A-Flat chemical liquid out of that tire and filled 4 bicycle tires with the excess.
The question for me becomes, who the fuck is selling faulty sealant?
Oh, key thought here, when the sealant has actually sealed, then it’s no longer exposed to any more outside air/oxygen, which means that whatever excess liquid sealant left in the tire, literally cannot dry. Unless it didn’t work right in the first place…
Sealant doesn’t just up and fully dry up sealed from the inside, unless your tire is totally fucked in the first place.
It can only fully dry out from the inside if it’s exposed to external air/oxygen, which in that case means the sealant didn’t work.
I think you folks are referring to Slime, that shit is pure garbage. You might as well cum into your tire and hope for the best…
Fix-A-Flat, even in the smallest amounts, are more than sufficient, even today. There’s no reason they should have advertised such a large can of sealant for an SUV, when a can for a lawnmower tire would have done just fine.
From the bucket of slush chemical out of that SUV tire, I probably could have sealed 4 to 6 or so bicycle tires.
Tires are tires yo, why would you expect bicycle tire sealant to dry up when I’m literally telling you that automotive tire sealant refuses to dry up and slushes around, yet still seals the tire, with lots of liquid slush leftover?
Sealant for tubeless bicycle tires is an entirely different formulation, and FaF is categorically ill-suited for bicycle tires.
Fix-A-Flat can and does dry into a lump. Bicycle tire sealant dries out to a powder, and is easy to clean out. Even better, just keep adding more sealant until it’s time to replace the tires.
I have seen bicycle rims corroded by FaF, but I don’t know how long it was in there. What I do know is that these bicycles came into my shop because FaF wasn’t sealing the punctures they were getting (goatheads and blackberry thorns).
FaF will clog valves, whereas bicycle tubeless sealant may or may not clog the valve; even if it does clog, bicycle sealant is easy to clean.
FaF is a temporary fix; bicycle tire sealant is explicitly part of running a tubeless setup and is sometimes used to help seat the tire; FaF comes with propellant and would be pretty awful to use when setting up tubeless wheels.
I’m pretty sure (but not certain) that FaF switched to a non-flammable propellant; tubeless bike sealant has no propellant
FaF is not designed for the higher pressures in many bicycle tires
I’m literally telling you, from experience, that Fix-A-Flat will not dry up into a lump inside the tire, it only dries up around the area of the leak where it started seeping out. It has to be exposed to oxygen to dry out, and the inside of the tire has limited oxygen, and once all that limited oxygen reacts with the Fix-A-Flat, the oxygen is gone and the FaF won’t dry any further.
The tire we just had replaced had run over a nail years ago, and had to be plug/patched from the inside. That patch proved to be a slow leaker though, which is when we decided to put in the FaF, to better seal the patch, which continued to hold air perfectly until the tire wore out and showing bare wire, so I’d say the patch+FaF were more permanent than the tire itself. Oh, I forgot to mention, it did not clog the valve at all, and it’s also tire sensor safe.
Anyways, once we had the tire replaced, there was around a pint of still completely liquid FaF sloshing around in the tire, the excess stuff never dried, it only dried up around the area of the patch where it started seeping out.
Now as far as my experience with bicycle tire sealant, that stuff didn’t even hold for a needlepoint sized leak caused by what I presume was a piece of a single wire strand off of a wirebrush. I’ll just as soon stick with good old fashioned bicycle tires plus tubes since I saw how absolutely useless bicycle tire sealant actually is first hand. At least patching a bicycle tube is super easy and basically guaranteed to hold if done properly.
What is the benefit of tubeless bicycle tires anyways?
What is the benefit of tubeless bicycle tires anyways?
Tubeless tires can be run at lower pressures without risk of pinch flats, also called snakebites because of the distinctive double hole in the tube. The wider working range of tire pressures allows riders to dial their tire pressure to the riding conditions, whereas clinchers (standard bicycle tires + tube) have much narrower pressure ranges. Varying the tire pressure has all kinds of benefits, especially with multi-surface tires, allowing the cornering blocks to bite into the surface earlier in turns. On gnarly chipseal pavement, the lower pressure means less fatigue, which quickly adds up over some miles. Failing to notice, or being unable to avoid, a pothole won’t cause a pinch flat. You can still dent your rim, but that’s mostly a non-issue with the ubiquity of disc brakes on bikes. On a clincher, you’re guaranteed a pinch flat if you hit something hard enough to dent the rim.
Tubeless tires provide the feel and higher traction of tubular tires (also called glue-ons, sew-ups) with greater durability, easier maintenance, and easier repairability.
For regions with goatheads and blackberries, tubeless is pretty much the only way to go farther afield. Tire strips can help, but they deaden the feel, mess with tire dynamics, increase rotational weight, and very rarely protect sidewalls. They are also (usually) horrible to install and can chafe tubes unless installed very carefully.
In regions without regular street-cleaning, with less frequent tire replacement, and with higher use of tire chains, it’s very common to encounter tire belting and fragments of tire chains. Tubeless bicycle tires are a day-saver. In my own experience, I can now ride those roads where it was previously common to get multiple flats. Before I switched to tubeless, one ride in particular in rural Oregon resulted in 8 flats in 40 miles. And then I was out of patches and spare tubes; day is over, call for a ride. All the flats were caused by tiny pieces of tire belting. I now check my tires once a week to pick out the tire belting I picked up, but I get zero flats.
Oh, I forgot to mention, it did not clog the valve at all, and it’s also tire sensor safe.
Our direct experiences are very different. And bicycles don’t have TPS.
If FaF was actually superlative for bicycles on any metric, we would all have switched long ago. At the very least, some pioneering shadetree bike mechanic would be singing its praises far and wide. I resisted the tubeless tire trend until late 2025 despite having worked on other’s bikes with tubeless, in part because I didn’t feel like building up new wheels. “Meh, everything I have is just fine.” I kick myself for having hesitated. It’s just so much better on all counts.
Oh, so tubeless is better for lower tire pressures? Okay, gotcha. My kevlar BMX bike tires are rated for 60psi, so of course when they’re brand new I pump them up to 90psi, so low pressure tires aren’t even on my radar.
Now of course as my tires age and wear out, I gradually reduce my max tire pressure accordingly, until they basically wear out bald and need to be replaced. I get that I shouldn’t overpressure my tires like that, but it makes BMX flatland tricks go way smoother.
Perhaps its just that there really isn’t any good viable sealant for such high pressures though, tube or tubeless tires. Patch/plug or replace is the only way to go for me, bicycle tire sealant is effectively useless in my experience. I’ve had patched tubes last more than 4 years without any leaks, until I manage to ride over something else to cause another puncture.
And no, our vehicle doesn’t have TPS sensors either, I just figured I’d mention the fact that modern FaF is advertised as sensor safe, and doesn’t clog the valve. Now I dunno about older formulas of FaF…
Dried sealant? What the fuck kind of sealant fully dries inside of a tubeless tire?
Disclaimer, this story comes from automotive tires with Fix-A-Flat, but still…
We just replaced a Fix-A-Flat tire last week on an old Hyundai, and the chemical had been in there upwards of 6 months or so. There was still more than a pint of excess liquid chemical in the tire.
Like hell, dude could have used a small can of the stuff meant for lawnmower tires, then topped it off with an air compressor, and not had over a pint of liquid sealant sloshing around in his tires.
So, if sealant for tubeless bicycle tires ends up drying up sealant, well phuck, either they didn’t sell you enough, or they’re ripping you off, probably both.
The only reason my friend had to have his Hyundai tire replaced was because of an alignment issue, which has since been fixed. But still, I coulda scooped the excess Fix-A-Flat chemical liquid out of that tire and filled 4 bicycle tires with the excess.
The question for me becomes, who the fuck is selling faulty sealant?
Everyone? Sealant dries up. It’s a thing.
Oh, key thought here, when the sealant has actually sealed, then it’s no longer exposed to any more outside air/oxygen, which means that whatever excess liquid sealant left in the tire, literally cannot dry. Unless it didn’t work right in the first place…
Sealant doesn’t just up and fully dry up sealed from the inside, unless your tire is totally fucked in the first place.
It can only fully dry out from the inside if it’s exposed to external air/oxygen, which in that case means the sealant didn’t work.
I think you folks are referring to Slime, that shit is pure garbage. You might as well cum into your tire and hope for the best…
Meanwhile, no its not everyone.
Fix-A-Flat, even in the smallest amounts, are more than sufficient, even today. There’s no reason they should have advertised such a large can of sealant for an SUV, when a can for a lawnmower tire would have done just fine.
From the bucket of slush chemical out of that SUV tire, I probably could have sealed 4 to 6 or so bicycle tires.
Tires are tires yo, why would you expect bicycle tire sealant to dry up when I’m literally telling you that automotive tire sealant refuses to dry up and slushes around, yet still seals the tire, with lots of liquid slush leftover?
Sealant for tubeless bicycle tires is an entirely different formulation, and FaF is categorically ill-suited for bicycle tires.
I’m literally telling you, from experience, that Fix-A-Flat will not dry up into a lump inside the tire, it only dries up around the area of the leak where it started seeping out. It has to be exposed to oxygen to dry out, and the inside of the tire has limited oxygen, and once all that limited oxygen reacts with the Fix-A-Flat, the oxygen is gone and the FaF won’t dry any further.
The tire we just had replaced had run over a nail years ago, and had to be plug/patched from the inside. That patch proved to be a slow leaker though, which is when we decided to put in the FaF, to better seal the patch, which continued to hold air perfectly until the tire wore out and showing bare wire, so I’d say the patch+FaF were more permanent than the tire itself. Oh, I forgot to mention, it did not clog the valve at all, and it’s also tire sensor safe.
Anyways, once we had the tire replaced, there was around a pint of still completely liquid FaF sloshing around in the tire, the excess stuff never dried, it only dried up around the area of the patch where it started seeping out.
Now as far as my experience with bicycle tire sealant, that stuff didn’t even hold for a needlepoint sized leak caused by what I presume was a piece of a single wire strand off of a wirebrush. I’ll just as soon stick with good old fashioned bicycle tires plus tubes since I saw how absolutely useless bicycle tire sealant actually is first hand. At least patching a bicycle tube is super easy and basically guaranteed to hold if done properly.
What is the benefit of tubeless bicycle tires anyways?
Tubeless tires can be run at lower pressures without risk of pinch flats, also called snakebites because of the distinctive double hole in the tube. The wider working range of tire pressures allows riders to dial their tire pressure to the riding conditions, whereas clinchers (standard bicycle tires + tube) have much narrower pressure ranges. Varying the tire pressure has all kinds of benefits, especially with multi-surface tires, allowing the cornering blocks to bite into the surface earlier in turns. On gnarly chipseal pavement, the lower pressure means less fatigue, which quickly adds up over some miles. Failing to notice, or being unable to avoid, a pothole won’t cause a pinch flat. You can still dent your rim, but that’s mostly a non-issue with the ubiquity of disc brakes on bikes. On a clincher, you’re guaranteed a pinch flat if you hit something hard enough to dent the rim.
Tubeless tires provide the feel and higher traction of tubular tires (also called glue-ons, sew-ups) with greater durability, easier maintenance, and easier repairability.
For regions with goatheads and blackberries, tubeless is pretty much the only way to go farther afield. Tire strips can help, but they deaden the feel, mess with tire dynamics, increase rotational weight, and very rarely protect sidewalls. They are also (usually) horrible to install and can chafe tubes unless installed very carefully.
In regions without regular street-cleaning, with less frequent tire replacement, and with higher use of tire chains, it’s very common to encounter tire belting and fragments of tire chains. Tubeless bicycle tires are a day-saver. In my own experience, I can now ride those roads where it was previously common to get multiple flats. Before I switched to tubeless, one ride in particular in rural Oregon resulted in 8 flats in 40 miles. And then I was out of patches and spare tubes; day is over, call for a ride. All the flats were caused by tiny pieces of tire belting. I now check my tires once a week to pick out the tire belting I picked up, but I get zero flats.
Our direct experiences are very different. And bicycles don’t have TPS.
If FaF was actually superlative for bicycles on any metric, we would all have switched long ago. At the very least, some pioneering shadetree bike mechanic would be singing its praises far and wide. I resisted the tubeless tire trend until late 2025 despite having worked on other’s bikes with tubeless, in part because I didn’t feel like building up new wheels. “Meh, everything I have is just fine.” I kick myself for having hesitated. It’s just so much better on all counts.
Oh, so tubeless is better for lower tire pressures? Okay, gotcha. My kevlar BMX bike tires are rated for 60psi, so of course when they’re brand new I pump them up to 90psi, so low pressure tires aren’t even on my radar.
Now of course as my tires age and wear out, I gradually reduce my max tire pressure accordingly, until they basically wear out bald and need to be replaced. I get that I shouldn’t overpressure my tires like that, but it makes BMX flatland tricks go way smoother.
Perhaps its just that there really isn’t any good viable sealant for such high pressures though, tube or tubeless tires. Patch/plug or replace is the only way to go for me, bicycle tire sealant is effectively useless in my experience. I’ve had patched tubes last more than 4 years without any leaks, until I manage to ride over something else to cause another puncture.
And no, our vehicle doesn’t have TPS sensors either, I just figured I’d mention the fact that modern FaF is advertised as sensor safe, and doesn’t clog the valve. Now I dunno about older formulas of FaF…