If you follow me on Twitter, you've probably seen my recent complaints about flats. After something like nine flats in nine weeks, I decided to make the move to a tubeless setup.
A super brief version of what that means: Instead of a tube in my tire, I'd have a couple ounces of sealant. The chief advantage would be that the sealant should fill any small punctures as they happen.
I encountered a lot of problems with my tubeless setup. The front tire held air without any issues. The back tire would leak air down to about 25psi but then stay there. That's low, but still rideable. However, at low pressures, tubeless tires can "burp" out air. A bump deforms the tire enough that a gap forms between the tire and wheel and air escapes.
I would go out for a ride with my tires full and come back with a dangerously-low rear tire. One one ride, I was so low that I pulled over to use my hand pump. While removing the pump, I inadvertantly removed the valve core. This resulted in completely deflating the tire, and knocking the tire's bead off of the wheel. I was carrying an emergency tube, but at this point I was so angry that I instead called a friend and asked for a ride. My buddy Joe, in his infinite kindness, refused when I asked if I could walk to his house and get a ride. He instead came to find me and offer me a ride home.
After this, I resolved that my bike would not leave the neighborhood until I'd solved this problem.
I let my bike sit in the corner to think about what it did for a couple of weeks. I spent the time vacillating between taking the bike into the shop and trying again myself.
I decided I'd give it one more try. Being a terrible scientist, I changed several variables at once. In any case, after nine miles in the neighborhood, my tire hadn't lost any air. (Or if it had, it was less than I could measure using the gauge on my track pump.)
Today I went for a ride. It was misting when I left but I was hopeful that it would get better. It turned out that misting was the nicest it would end up being on tonight's ride.
Riding in the rain in Houston is an adventure. Most of the roads are crowned for flood control. Bike lanes are on the outside of the road. That means you're riding through all the detritus that the rain is washing off the road. Water in the road ranges from still and black to quick moving. It's especially fast near storm drains, which take up the entire bike lane.
As I pulled off of the road to check my map, I heard the telltale sound of air escaping my front tire. I lifted my bike and spun the wheel as fast as I could. This was a technique I'd seen in several YouTube videos testing tubeless setups. The idea is to force sealant to the outside of the tire. I figured this would be more effective than the slow going of the bike lane.
After about a minute, I remembered reading that you can clean these sealants with water. Riding through a couple inches of water was probably not great for the sealant. Standing here in the rain couldn't be helping much either. I ducked under cover to consider my options. I was at the corner of two bus routes but only halfway through my planned ride. If the tire wouldn't seal, I'd have to bus home soaking wet. Meanwhile, the tire continued to hiss as it spun.
As I felt the tire getting soft, I started to get worried. I carry a pump. Air pressure is not a concern as long as the tire maintains enough air to keep its bead on the wheel. But I needed the seal. I thought about what might be more effective about getting the seal to form. Interestingly, I'm not able to find anything about this online. Most punctures seal themselves so rapidly that they're not even noticed.
I figured the sealant is a liquid - it will flow to its lowest point. So I set the puncture on the ground. After a few seconds, the hissing stopped. I spun the tire to test it, and the hissing came back. I repeated the process and... success! My tire was no longer leaking air! I gave it a bit of a test. It was lower on air, but well within the realm of comfortably rideable. I decided not to risk another valve catastrophe. I'd ride home on the lower pressure tire. I'd go almost straight home but stick close to the bus route.
When I got home, I'd heard no other indicators of a renewed leak. My measurement indicated I'd lost about half the air. I brought the tire back to full pressure and still heard no signs of leaking.
I'll have to do some research into the wet weather interaction with tubeless sealant. Even if it's a problem, it won't make me not ride while it's wet out. But I'll probably avoid those semi-flooded bike lines when I can.
I think the change that solved my problem with the rear wheel was switching to a different valve. I'm now using [Muc-Off valves](https://us.muc-off.com/collections/no-puncture-hassle/products/black-tubeless-presta-valve-pair). These come with a few differently shaped gaskets to allow you to choose the best option for you. Also, they include a gasket for outside of the wheel.
I started this as a tweet thread and it ended up as 974 words before this paragraph. I'm thinking about spinning up a second blog for things that are too long for a tweet thread but too low quality or off the cuff for a blog post. I know that's basically the original elevator pitch for Medium's service, but I certainly won't be using them.