In part 2, the mechanic from ExpertVillage pontificates on the pros and cons of tubed and tubeless tires for mountain bikers.
If you missed Part 1introduction tubeless tires, you can get it here: Part 1: Tubeless Tires Visually Explained
The mechanic from ExpertVillage gives a nice introduction to tubeless tires. It’s great for those of us who like to ingest information without reading it.
mmm… passive learning.
What a tubeless rider needs to bring on a ride
Carrying a spare tube with you when you ride is one of the best ways to repair a flat on the trail. Do not rely on always being able to repair a flat tubeless tire in the field. Bring a patch kit too if it is a long ride (or a long walk out). You might get a flat in the tube.
Tweezers can be very useful for removing glass, sharp needles or thorns from the tire casing. You have to get these out before you install a tube or you will have a new flat right away.
After sealant plugs a leak you may have lost some pressure depending on the size of the hole and how long it took to seal. A very good mini pump and a CO2 cartridge inflation device can be helpful if you are in a hurry to repair your flat or get it to a rideable pressure. A mini pump that works well is adequate but slow.
A piece of fabric or other fibrous material will be very handy if you fracture a sidewall. A piece of duct tape wrapped around the drive side chainstay protects from small nicks and can be useful for trail side repairs. Or a few wraps around the seat tube can be enough to repair a large tire hole, broken shoe binding, or any number of things. Duct tape is great!
Carry tire tools, unless you are very confident that you can remove and replace the tire without them.
What Spare parts to bring on a ride
If you race or take your recreational riding seriously you should acquire some of the unique parts in the tubeless wheels. You want these to be around when you need them. I recommend the following:
You can get away with one type of tire but it’s a good idea to have a few different tires for different riding situations. The extra tires will also serve as spares if you need a tire quickly. One will do. It can be one from the last set you replaced, as long as it is in good enough shape to ride.
These are not likely to be a problem for you unless you use tire tools. But they are a proprietary design and will not be available from every dealer. Two spares should be enough for most situations. Store the spares carefully so that they are not damaged before you install them.
These are probably not necessary for most people, but if you ride hard in a rocky area or have a history of damaging rims, it won’t hurt to have a spare.
Though it’s rare, these can be damaged on the trail. And, if you flat and have to use a tube, you have to remove the valve and carry it with you in a pocket or your tool bag. It might get lost. Two spares should be enough. They are small, so put them someplace where they will be easy to find.
These are not a proprietary part, but it’s a good idea to have some around. A stick on the trail or a dropped chain can take a few out. 2 of each length at a minimum, and 6 of each are better.
Adhesives and sealants
If you live around trails with thorns or plan to ride in that kind of terrain, Slime or a similar liquid sealant is a good thing to have. A tube of sew-up rim cement can be very handy in a pinch too. It can be used for a lot of temporary repairs on the rim strip and inflation valve.
It’s certainly not necessary for everyone, but a spare set of wheels can make everything easier if you ride a lot or race. You have more time to make repairs on your good wheels. You can spare them from the wear and tear of training rides when conditions are wet or rocky. The spare wheels can, and should, be built with heavier rims and inexpensive hubs too.
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Tips and Tricks for Tubeless Tires
A tire must be tubeless-compatible to work without a tube. A tubeless tire will be clearly marked as such on the tire sidewall unless you are using a conversion kit.
Seat the tire beads on both sides of the inflation valve to prevent gaps that allow air to escape
Rest the tire beads uniformly in the center channel of the rim. Beads must not fold or deform prior to tire inflation. Any odd deformation will allow air to escape during inflation
Eliminate all gaps between the tire bead and the rim strip that may allow air to leak. If a gap is suspected, pull the tire towards the rim opposite from the gap. This will pull the bead with the gap into a sealed position on the rim strip
Seat the inflation valve against the rim strip or air will escape around it during inflation. Secure the valve retaining nut by hand only to ensure easy removal
When possible, inflate a tubeless tire initially with a larger hand pump, floor pump or CO2 cartridge. The low air flow rate in some small hand pumps will not initially inflate a tubeless tire
If none of the above has solved the problem, the tire may be damaged. Substitute a tire that is known to work and try again. If it inflates, the original tire is probably damaged or defective and must be replaced
The tire inflates initially, but then loses air quickly
*If air comes out the valve hole of the rim, it does not necessarily indicate a problem with the valve
A tire must be tubeless-compatible to work without a tube. A tubeless tire will be clearly marked as such on the tire sidewall unless you are converting it.
New tires that have never been seated on a rim may be easier to setup tubeless after putting a tube in the tire. This helps to remove folds in the tire’s form from packaging. These folds can often cause air leaks. Usually a night with a tube will shape the tire enough that it can be seated tubeless on a wheel.
Clean the rim strip before assembly and inflation. Dirt on the rim strip could cause a leak
Look for cuts, tears, or gouges in the rim strip that could cause a leak. Use care when mounting or removing a tire so as not to damage the rim strip. If a rim strip is damaged, it must be replaced to prevent damage to the wheel tire or yourself!
Seat the inflation valve against the rim strip or air will escape around it. Secure the valve retaining nut by hand only to ensure easy removal
Inflate the tire to between 50 and 60 psi to properly seat the tire beads. (Note: Some tires may not require a full 50-60 psi to seat properly)
An installed tubeless tire fits too tightly to be removed
Push one tire bead at a time into the rim’s center channel. Beginning at the valve, pull one of the beads up and over the side of the rim. Extreme care should be exercised if a tire tool is used in this process. Excessive force on the tool could damage the rim strip or tire bead.
Come back for the final part on what to bring on a ride or subscribe to the feed.
Removing and replacing the inflation valve from a tubeless rim
To remove the inflation valve
Loosen the nut that retains the valve. Push the valve body up through the rim. Keep track of the valve and nut so that they are easy to find when you use them again.
To replace the inflation valve
Clean the area where the grommet will seat on the rim strip and the grommet itself. If you used any caulking or sealant on the valve previously make sure you remove it thoroughly. Automotive brake cleaner is usually good for cleaning the rim area since it does not leave a residue.
Make sure the hole in the rim strip aligns with the hole in the rim.
Push the valve through the rim strip and seat the grommet in the central groove in the rim strip.
Tighten the retaining nut by hand only. You might have to remove it on the trail if you have a flat.
Truing the rim
If you don’t need to replace spokes you can true the rim with standard tools without removing the tire or rim strip. If the nipples are binding you will need to lubricate the spoke threads or nipple seat. Use a light oil on these sparingly.
The spokes can be replaced in the same way that you would replace them in a traditional wheel.
Make sure the spoke is the right length. If the spoke is too long it might contact the rim strip and puncture it.
Spokes on the Mavic UST wheelsets are usually only dealer replaceable or require a send off to the factory.
Come back for the next part for more tips and tricks or subscribe to the feed.
Replacement strips and inflation valves for most of the tubeless tire systems are available.
Rest the tire beads uniformly in the center channel of the rim. Beads must not fold or deform prior to tire inflation. Any odd deformation will allow air to escape during inflation. Eliminate all gaps between the tire bead and the rim strip that may allow air to leak. If a gap is suspected, pull the tire towards the rim opposite from the gap. This will pull the bead with the gap into a sealed position on the rim strip.
Seat the tire beads on both sides of the inflation valve to prevent gaps that allow air to escape.
Seat the inflation valve against the rim strip or air will escape around it during inflation. Secure the valve-retaining nut by hand only to ensure easy removal.
When possible, inflate a tubeless tire initially with a larger hand pump, floor pump or CO2 cartridge. The low airflow rate in some small hand pumps will not initially inflate a tubeless tire.
If none of the above has solved the problem, the tire may be damaged. Substitute a tire that is known to work and try again. If it inflates, the original tire is probably damaged or defective and must be replaced.
Removing and replacing the rim strip
To remove the rim strip
Handle the rim strip with care at all times. If it is scratched or torn it won’t seal air well.Insert a blunt tool into the valve hole in the strip, just under the strip but not into the hole in the rim. The curved end of some tire tools works well.
Gently pry the strip up away from the rim so there is a clear space under the strip and over the brake walls on one side.
Slide a round screwdriver blade or other smooth tool under the strip and pry the strip up high enough with it to allow the tool to extend completely across the rim’s width under the strip. The strip should rest on this tool shank and pull it into the rim under tension.
Remove the tool you used to lift the strip away from the rim.
Slide the screwdriver around the entire outer circumference of the rim while it is under the strip and break the strip loose from the rim.
Repeat this operation but gently push the rim strip off to the side where it is pulled away from the rim as you slide the screwdriver along the rim. The strip should be pushed completely over the rim brake wall after sliding the screwdriver a few inches along the rim. The entire strip will come off easily after sliding the screwdriver around the rim 90 degrees or so.
To replace the rim strip
Handle the rim strip with care at all times. If it is scratched or torn it won’t seal air well.Align the valve hole in the strip and rim. Insert the valve, a punch, or a Philips screwdriver through the holes to maintain that alignment. The ‘U’ shape of the rim strip should face the same direction as the ‘U’ shape of the rim well.
Gently push the strip over the brake wall on both sides of the valve a little at a time until it is completely over the brake wall. Working on both sides at once will generally leave the valve holes aligned as you install the strip.
Make sure it is seated completely into the central groove of the rim after it is slid over the brake wall. Shift it gently into place. Do not use sharp tools to do this.
If it is necessary use part of the procedure outlined for removing the strip to seat it uniformly into the rim groove. Slide the screwdriver shank under the strip and around the rim to pull the strip into alignment with the rim.
This method can also be used to re-align the valve holes if they shifted during installation. Slide the screwdriver under the strip and then around the rim in one direction only. This will advance the strip around the rim in that direction. Do this until the hole in the valve is aligned properly. Do not enlarge the hole in the rim strip.
Come back for the next part for more tips and tricks or subscribe to the feed.
This is the 2nd post in our series of tubeless tire tips. If you’ve missed the first part about detecting leaks, you can read it here: Part 1
Tubeless Tire Leak Repair (leaks that are not due to a puncture or casing failure):
Leaks at the valve
Remove and inspect the valve. If it is damaged, it will need to be replaced. If you are out on the trail you will need to install an inner tube to complete the ride.
Leaks under the tire bead
This type of leak requires new parts or using an inner tube. In an emergency a caulking adhesive or thick, non-hardening adhesive (such as traditional sew-up tire glue) can seal up a small leak between the tire and rim strip temporarily. It should be used only as a temporary measure to complete a ride when spares are not available.
Leaks through the tire casing
Occasionally you might have a leak in an otherwise serviceable tire casing that allows air to escape at an unacceptably high rate. A bubble test will reveal the location(s) of the leaks. Normal patching methods will work, or a fluid tire sealant such as Bontrager Super Juice or Stan’s might reduce the leak rate too. If sealant is used you should hold the wheel sideways (rotational plane horizontal) to allow the sealant to cover the leaks.
Stay tuned for the next part on rimstrip repairs or subscribe to the feed.
It seems everyone is going tubeless these days. From mountain bikers to now road bikers. Even the on the Tour de France, they’re are riding tubeless. So with that, we’re putting together a series of collected tips for tubeless riders. Everything from repair and installation to what you need to bring with you on a ride. Hope you find them useful!
Repair and Leak Detection for tubeless tires
General tubeless repair strategy
If you can’t detect the leak (see leak detection below) and you aren’t in a big hurry, you can replace components one at a time until the leak down rate is acceptable. This lets you isolate the cause of the leak to the defective component and reduces the cost of the repair.
You can also use a tube in the tubeless tire or install a standard tire and tube to repair a leak on these wheels. You have to remove the inflation valve to do it, and you can also exchange the rim strip for a lighter one to save a little weight too.
Tubeless Tire Punctures
Normal patches will work on the inner surface of a tubeless tire. The inner surface of the tire must be clean, dry and abraded lightly to be patched reliably. “Glue-less” patches work also. The same rules apply to make sure the patch adheres well. The inner surface of the tire must be clean, dry and abraded lightly to work well.
Casing Failure (pinch flat or sidewall blowout)
It is often possible to repair a damaged casing in order to ride out on a given day. It is only good for an emergency repair so replace the tire before the next ride.
Use a dollar bill or some other fibrous material to cover the fracture in the casing on the inside surface of the tire. There is a limit to the size of the hole you can repair this way. Some adhesive on the material can help hold the reinforcing material over larger holes. You will need to install a tube in the tire after you repair this type of failure unless you are using a fibrous material that is not permeable to air and it is sealed to the casing well. You should not inflate the tire more than necessary to finish the ride.
Leak detection: Bubble Test
This test is the best way to find leaks in the tire. You can find multiple leaks in this type of test too, a common problem with some types of thorns. The bubble test is not always a reliable way to locate leaks between the bead and rim strip. Air that leaks anywhere around the circumference of the tire bead will almost always come out only at the inflation valve. The spoke nipples typically seal well enough that air will not make it through the spoke holes.
Immerse the tire and rim in water. You need to have a fairly large container for the water in order to submerge the full tire and rim for 4 or more spoke holes. A bathtub, sink or large utility basin or any other large vessel is ideal for this test.
If an initial bubble test shows that the leak is inside the rim cavity (bubbling through the inflation valve clearance hole in the spoke bed of the rim) and you want to isolate a leak location, then seal the valve outlet area with an oil based clay or other non-permanent caulking material and try to force the bubbles out of the spoke holes near the leak. It is generally easier to substitute parts to cure a leak.
You can’t perform a bubble test on an unmounted tire or if it leaks too fast to immerse. If you have a tire that leaks but can’t inflate it enough to use the bubble test to find the leak, and you can’t hear the leak, you have to substitute components to repair the leak. You can replace everything that might be leaking to fix it fast or you can replace things one at a time to find the defective part. Then you can replace the part that is defective instead of all of the parts in the assembly.
Leak detection: Aural Test
If you can inflate the tire you can listen for leaks. You have to be in a very quiet environment to do this. Not all leaks are detectable in this way.You can detect some internal leaks by slowly rotating the wheel as it is partially submerged in water (about 6 inches deep). As you rotate the wheel and an internal leak is submerged you will hear a noise caused by the bubbling water inside the rim. You cannot see an internal leak but you can find it’s general location in this way. This can be helpful when you are trying to find a leak between the tire and rim strip.
If you hear a leak in the tire, test the likely spots with saliva. If you cover a hole with saliva the noise of the air escaping will get louder and also be visible. This can be useful when you’re out on the road or trail.
This is probably the most ludicrous example of why you need to go tubeless. If we all road tubeless and the roads were made of paths of death, there’d be a lot more room for bicyclists. We’d all be really good at trackstands too.
Really, really good at trackstands.
They’re using Stan’s NoTubes sealant. Can anyone identify the tire by the tread?
The enigmatic Stan’s from NoTubes.com shows how to convert your regular road wheel into a tubeless wheel. He uses his NoTubes road conversion kit and the Hutchinson Road Tubeless Fusion tire.
He makes it looks pretty easy.
keep looking »