A valve stem and valve system and sealant application tool for a tubeless tyre setup

A valve stem system for a tubeless tire setup for a wheel including a rim and a tire, the valve stem system comprising:

• a valve stem body comprising at a first end an outer valve stem configured to receive a valve core, and at a second end an inner valve body extending in an air reservoir defined between the rim and the tire mounted on the wheel;
• a first valve, comprising a valve outlet port at the inner valve body, configured to allow air passage between the outer valve stem and the air reservoir;
• a second valve, comprising a valve outlet which, at the inner valve body, separate from the outlet port of the first valve, configured to allow sealant passage from the outer valve stem into the air reservoir;
• and
• a filter disposed between the first valve and the air reservoir, the filter configured to filter sealant entering the first valve from the air reservoir;
• wherein the first valve is a movable non-return valve body disposed in the valve stem body, and is configured for longitudinal displacement within the valve stem body upon receiving the valve core in the outer valve stem, for the first valve to open and allow air passage between the valve core and the air reservoir.