Workshop & troubleshooting: mounting tubeless tyres

How can tubeless tyres for road bikes and gravel bikes be mounted quickly, smoothly and safely? Felix Schäfermeier, Product Manager Road Bike at Schwalbe tyres, is an expert in this field and gives advice on how to mount tubeless tyres like a pro. He furthermore knows some tricks for troubleshooting.

How to glue in tubeless rim tape

If there is not yet tubeless rim tape in the rim already, you’ll need to glue in some. Before gluing it in, clean the rim bed, ideally with “alcohol”. When gluing in the rim tape, let it slightly overlap and then press it in carefully with your thumb.

Tip:

• Always make sure the rim tape has the right width. As a rule of thumb add one to two millimetres to the inside width of your rims.
• When changing a tyre, always check the rim tape for damage and tears.
• For rims with a small shoulder diameter (the part of the rim that supports the tyre bead, i.e., where the tyre seals bead and rim), it is advisable to glue in the tubeless tape in two layers. If you do so, the tyre will slip into the rim without any effort. Above all, this makes pumping up the tyre significantly easier, as no air will escape between tyre bead and rim shoulder.

How to insert tubeless valves

Do not “pierce” the valve hole with a screwdriver or similar tool, as this makes tears more likely. Instead, softly mark the area with a small screwdriver and then cut a small cross with a knife or cutter.

Then carefully insert the valve. Make sure that it is thoroughly screwed in and sits firmly in the hole.

Tip: Schwalbe offers special tubeless valves that can be easily tightened from the inside with a hexagonal key.

How to mount tubeless tyres

The first step in mounting a tubeless tyre is similar to mounting a clincher tyre, just without the inner tube. First insert one side into the rim bed, then the other side – start opposite the valve and work your way step by step towards the valve.

Tip: If the tyre appears too small or narrow and cannot be pushed over the rim flange on the opposite side, you can “gain circumference” as follows: First place the second tyre bead directly next to the other one, both are atypically on one side of the valve now. Then carefully push, i.e., move the second bead over the inner valve fitting and carefully press the rest of the tyre sides into the rim flange – roll the tyre back and forth to do so.

How to inflate tubeless tyres

Rotate the wheel until the valve is somewhere between seven and eight o’clock position. If necessary, unscrew the valve core and inflate the tyre to the recommended level. Oftentimes you’ll hear a cracking noise when the tyre settles snugly into the rim. Make sure the tyre sits evenly on the rim and does not wobble. Then remove the pump head, screw the valve core back in and inflate again.

How to fill in tubeless sealant

Rotate the wheel until the valve is in a position between six and seven o’clock. Unscrew the valve core with a special small tool supplied with the tubeless kit. Fill with sealant. Screw the valve core back in. Inflate and let the wheel spin several times by pushing it with your hand. Press down onto the ground.

Tip: Ideally, do a test ride right away so that the sealant spreads inside the tyre in motion.

Troubleshooting for tubeless tyres

Problem: Tyre does not sit properly in the rim bed or cannot be inflated.

Solution: Coat the lips of the tyre with special mounting fluid to smoothen it and make it fit tighter to the rim flange.

Apply a second layer of rim tape.

Problem: air escapes from the valve

Solution: Apply small self-adhesive patches to the valve hole from the inside. Cut a small opening – see above –, push the valve through it and screw it in tightly.

Problem: puncture on the road

Solution:

• Do not rotate the defective area to 12 or 1 o’clock position to examine it. Instead, position the tyre so that the sealing milk can run to the hole and seal it. Then inflate very carefully.
• Larger cuts can be sealed with special tubeless first aid kits like “Dart” from Stan’s No Tubes.
• If the hole is too big or the cut too long, insert a replacement tube.