Tofu Ball

#cycling

So I have been a “casual cyclist” for some time now. From cross-country bike to road bike, I have used at least 4 bikes since I found myself enjoying cycling. However, one thing have always been plaguing my cycling journey: blown-off tubes. I never really understand types of blown-off tubes, which is why I put a quotation mark on “casual cyclist” as even though I (previously) ride a lot, my knowledge about cycling and bikes is pretty limited.

After I moved to Bay area, and started my “extreme” but scientific self-designed weight loss program (I might discuss this later in this blog), I found myself in need to find a sports program to help maintain some of my overly-high (compare to my ideal body composition) muscle mass to help maintain my base metabolic rate. I tried VR games and cycling.

Well, it's more like a cycling rehab to me, and I definitely loss a lot of strength and endurance for not on wheels for 4 years (there are times I did ride some, such as when I just got my current bike second-handed). I installed in-line brake levers to better help me riding in an endurance bike position and tuned my brakes, also re-lubed my drive chain.

After all these “upgrades” was done, I found myself having a flat front tire, maybe due to tube aging (the tubes are still the ones I got from the previous-owners when I bought the bike ~2 years ago). I bought some new tubes and changed it, pumped it up with my small on-bike hand pump, and didn't think too much.

I went on a ride and it was fine (in the sense of the bike mechanically, but my body got some serious problem and it's off-topic from this blog so let's ignore it). Next time I want to ride to my friends' home to help a friend with her homework, and my back-tube blown off while I'm on the road. I still didn't understand why the tube are blown off like most of the times I got a blown-off back in high school.

I got home, and was thinking about the problem. I searched for a lot of information and start to know different types of flat such as puncture flat and pinch flat, or in my case, after I inspected the tube, a valve flat: the rubber under the valve got a massive opening.

This is when I start to recall all my previous flats during high school (when I ride a lot). There are maybe 30% puncture flat, 10% valve flat, and other 60% (can be even higher) are all pinch flat. I don't even have a metered floor pump at that time (so I never know what PSI my wheels are on compare to the numbers on the tires).

I also recalled why my current bike is so easy to get flat compare to my high school one: my high school bike, being a low-end road bike, uses a pair of 700x28c and much harder tires, while the previous owner gave me a pair of 700x23c soft and smooth tires on my bike. I also only pumped my current bike with a weak hand pump.

After a lot of reading, I decided to go down the rabbit hole of road tubeless with wider tires (700x28c as it's the widest safe/non-conflicting choice for upgrading on a bike designed for 700x23c). With its benefit of avoiding almost all pinch flat (how hard will it be to pinch outer tires? even softer and less-protective ones) and self-healing of small punctures (sometimes even bigger punctures, I watched this video on real world testing of how big a hole can be sealed and was impressed). Meanwhile valve flat will just be impossible (besides installation problems or nuts weakening which you can fix very easily with bare hands and re-pump your bike) as valves are now separate components, directly installed on the rim and not connected to some welding points on very thin rubber.

It's truly a rabbit hole (spoiler: I went down all the way and it's perfect). I did a lot of further research on it and received a lot of conflict information. For example on Stan's (a lead tubeless components manufacturer in bikes) FAQ page It says

Section: ROAD TUBELESS Q: Can I convert any road wheel to tubeless? A: It is our experience that most 700c road rims can be converted to tubeless with two layers of Yellow Tape, a Universal Valve, sealant and a Road Tubeless tire. Please check with the manufacturer of your rim for their recommendations on tubeless use prior to any conversion.

Section: TUBELESS CONVERSION Q: Can I convert my non-tubeless mountain bike rim to tubeless with tape and valve only or will I need a rim strip? A: No. “Tape and Valve” conversions are only appropriate with rims that are labelled as “Tubeless Ready,” “Tubeless Compatible,” or similar. The BST (Bead Socket Technology) profile developed by Stan's NoTubes was a departure from traditional bicycle rim design and its core concept is the basis for the vast majority of “tubeless-ready” rims and wheels on the market today. Stan's Yellow Tape is not, by itself, a tubeless conversion for older, traditional, non-“tubeless-ready” rims. These older rims require the use of a Stan’s NoTubes Rim Strip (now discontinued) to re-shape the rim bed to achieve a safe, secure tubeless setup This reshaping creates a much more secure BST-like fit between the tire and the rim, allowing for easier inflation/setup and eliminating burping. While Stan's Rim Strips have been discontinued, we continue to provide information and resources to assist in converting non-tubeless-ready wheels.

When I open the “information and resources” page, it discussed a lot about rim strip but it's all about mountain bike, it started to confuse me, e.g. are tubeless conversion good for road but not good for mountain bike? Then I found this video How To Setup Tubeless Road Bike Tyres – Everything You Need To Know from BikeRadar and it suggests mountain bikes can do tubeless conversion safely due to its low pressure but road tubeless needs to have specific tubeless-ready rims and tires. This Tubeless Tire Compatibility article from Park Tool (lead manufacture of tools for bike mechanics) suggests

A tubeless ready rim will have a sidewall with a hooked design, which helps catch and hold the bead. Older rims will appear rounded without a hook shape. The shape of the rim will force the bead up snug against the outer hook, and will have a deep section in the middle to make it easier to remove.”

while it's known that automotive tubeless rims are hookless and some bikes also have hookless rims for tubeless setup as said in this article: The Hookless Bead Rim: How It Works & Who They’re For – by ENVE Composites. In the previous Will it Seal video (timestamp included in the link) GCN presenters personally endorsed these Cinturato Velo tires (they mentioned these are sent by the manufacturer for free, but the video doesn't have a link to buy these tires in the description, the video also doesn't have the “include paid promotion” tag on YouTube) for their protection, and protection is one of the major selling points of these tires according to manufacturer's website. Because I don't have much experience in picking tires, I chose this one as my new front tire accordingly and found out there are clear marking on both the tire and it's packaging: “Does not fit TSS (hookless) rims” which is conflicting to

As you can see, in a tubeless world, hook-beads serve no purpose assuming that the rim and tire are interfacing correctly.

claimed in the article about hookless rims. It's also conflicting with this part of the Stan's FAQ page:

Section: Wheels & Rims Q: What tires can I use? A: Road tires, or any tire you intend to inflate over 40psi, must be specifically labeled for tubeless use, as these tires will have beads designed specifically to accommodate the higher loads seen in a high-pressure tubeless application. When in doubt, consult the manufacturer of your tire. Road tires that are labeled “Use only with hook bead rims” should never be used tubeless.

(For more background knowledge on tubeless bike setup, just watch some top result videos from YouTube on bike tubeless installation, I was only discussing conflicting information I received.)

With all these conflicting information, I proceed with tubeless-related purchasing and installation. I got the Cinturato Velo for front tire and Tufo Comtura 3 TR for my back tire for its bead to bead high strength fiber protection. I tried to install my back tire first (as it was flat since my previous ride and I never changed its tube for going tubeless directly). I very unprofessionally (some of the previous research I mentioned are done after this attempt) put 1 layer of tubeless rim tape directly on top of the previous tape for inner-tube, and didn't stretch the tubeless rim tape enough to reduce bubbles, tried to fit valves and put tire in. I found is super hard to put the tires in, I almost want to give up once but I finally did it.

Then I found out I can't pump the tire up/seat the tire with my newly bought up-to-80psi car pump (because it's airflow is too slow, or not as fast as canister or compressor), even with sealant in. There's a big leak near the valve and it looks like the valve is preventing the tire near valve from touching the aluminum of the rim (turns out a well-seated tire doesn't need to have the tire bead touching rims in a hooked tubeless setup as I lately find out). So I brought both tubes and new tires to a bike shop and they are very helpful. I told them it's urgent as I need it back in 2 days and they think it's possible to have them done in the day between. A day later I got a call from them saying they don't have correct rim tape for my bike so they need to special order it. I decided to get them back to try DIY again since I need to move the bike pretty urgently. They didn't touch my back wheel but gave me a front wheel with my new front tire already on it (reversed) and my original good inner tube inside but rim tape was changed to yellow Stan's tubeless rim tape, not fully covered with 2 layers but looks to be correctly installed (implies tape size does fit). This means they probably didn't have enough correctly-sized tubeless rim tape in stock and tried to put back as what I have gave them (my front tire was inflated with an inner tube with old tires when I gave them). They also gave me back the old rim tape (it's a rubber band actually so it's reusable) and old tires from the front tube. They didn't charge me anything for their failed attempt so I really appreciated their work (I'll visit them again next time if something went wrong with my bike that I can't fix myself, due to there fair price for parts and labor and friendly service).

One thing I found very valuable from this bike shop experience is that when I gave them my wheels and new tires, I told them my rims are not tubeless-specific but the new tires are tubeless ready. They doubled checked the labels on my new tires and found it doable. This increased my confidence largely as now I can have some very basic but reliable (since it's from direct experience of mechanics) information about the feasibility of road tubeless conversion.

This time I got myself more prepared, I got more sealant: a bottle of finish line fiber-based sealant (many people criticize it for its no-refresh-needed claim, but by reading Amazon review I think they are mostly MTB riders that have porous tires, road tubeless tires needs to withstand much higher pressure thus are less porous and road riders are giving positive review to this sealant. I chose it mainly for its less refresh needed and easy clean up property, compare to normal latex sealant). New valves that have a shape that looks like can help with the falsely-perceived seating problem, and CO2 canister inflation system.

Turns out after the tire are correctly seated by CO2 with popping sound, it doesn't matter if the tire is touching the inner side of rim or not because it is pushed by air pressure against the bead to seal itself. The new valves are problematic (with my too-big rim tape puncture for the valve) as it's leaking through the rim tape hole, I had to add double o-rings to fix this. In the end it worked and my car pump can pump air in both tires and they hold pressure (verified by squeezing tire by hand) over night after I fixed leaking. The back tire (Tufo) sealed after 1 attempt of inflation after seating besides the valve leaking, adding another o-ring and re-pump find it completely sealed. The front tire installation is much easier and that makes me realize the back tire is so hard to put on is because of the all-round high strength anti-puncture fiber instead of being tight for tubeless. The front tire took 2 round of pumping to completely seal the beads. This time I also watched in detail about how to apply rim tape and correctly applied them by stretching hard.

The last obstacle is clearance. As suggested by many people, a 700-23C bike frame and fork should fit 700-28C, and they do fit. However, my front brake is conflicting with my front tire after inflation. I tuned the brake tighter so it give more room from its brake arm to the wheel, and installed the wheel tightly in the lower position in its axis clearance.

With all these solved at night, the next day I verified they still hold pressure (by squeezing again) and took my now tubeless bike for a ride. I ride ~25km and it doesn't loss pressure or have front wheel touching brake again. I call this a success tubeless conversion.

“Whew, That was one hell of a ride” down the road tubeless rabbit hole.

Please bare me with my bad writing, not proof-reading due to feeling so tired after finish writing it, and disabled grammarly for obvious privacy reasons. It seems grammarly have changed their ToS since then(?) according to their FAQ on this topic but I still don't trust their service (and I'm no longer a student that need to finish college writing class UwU).