Tubolight Diamana Tire Insert Pair XHD 27.5 x 2.6-3.0"

The lightest mountain bike tire insert on the market.

If we look at how the tire compresses and rebounds on impact, we can see that the whole process happens very quickly. During this time, the tire casing returns to its original shape even before the suspension begins to compress. This is enhanced by a high tire pressure, but at the same time can be mitigated by a lower tire pressure and is actually the reason why a lower pressure tire provides more traction.

On the Diamana, the side channels are shaped to create a Venturi effect, which means that the speed of the airflow through the channels increases as the channels become smaller. This is the same principle of the ground effect of Formula 1 cars and is required to accelerate the air from the outer part of the insert to the inner part between the insert and the rim bed. Air is trapped in the inner part and takes much longer to return to the outer part, leaving very little air at the point of impact during the entire impact moment.

The knobs on the top are inspired by knobs on golf balls and, together with the wave shape, ensure that the air does not bounce back to the tire, resulting in a strong rebound effect, but flows into the side channels.