Are you riding at the right pressure?
In the Signature Configurator you can assemble your bike in full accord with your own wishes and ergonomic requirements. But the riding qualities of a bike are not set by frame geometry and components alone. Key to making riding a pleasure not a pain are the tyres, and in particular tyre pressure.
Tyre pressure
Cycling is best when the tyres are ridden with the advised tyre pressure. A general rule of thumb: the higher the tyre pressure, the lower the rolling resistance. In addition, there is less chance of puncturing.
Cycling with a low tyre pressure decreases the life span of the tyre. Tears appear in the sides of the tyre and wear increases. The advantage is that comfort increases, because the lower pressure means that the tyre feels better sprung.
Wide tyres are generally ridden with a lower tyre pressure. Thanks to the greater volume, this does not effect the rolling resistance, puncture protection and life span.
The proper tyre pressure depends on the size and the weight placed on the tyre. This is mainly determined by the weight of the cyclist and the baggage. The minimum and maximum allowable pressure is usually stated on the transfers and the sides of the tyres.
|
|
Recommended tyre pressure |
Tyre width
(mm) |
Bar |
PSI |
|
Min. |
Max. |
Min. |
Max. |
|
20 |
8.0 |
12.0 |
115 |
175 |
|
23 |
8.0 |
12.0 |
115 |
175 |
|
25 |
8.0 |
11.0 |
115 |
160 |
|
28 |
4.5 |
6.5 |
65 |
95 |
|
32 |
4.0 |
6.0 |
60 |
90 |
|
35 |
3.8 |
5.5 |
55 |
80 |
|
37 |
3.8 |
5.5 |
55 |
80 |
|
40 |
3.5 |
6.0 |
50 |
90 |
|
42 |
2.8 |
4.5 |
40 |
65 |
|
44 |
2.5 |
4.5 |
35 |
65 |
|
47 |
3.0 |
5.0 |
45 |
75 |
|
50 |
2.5 |
4.5 |
35 |
65 |
|
54 |
2.5 |
4.5 |
35 |
65 |
|
55 |
2.0 |
4.0 |
30 |
60 |
|
57 |
2.0 |
4.0 |
30 |
60 |
|
60 |
2.0 |
4.0 |
30 |
60 |
|
62 |
2.0 |
3.0 |
30 |
45 |
Balloon tyres
Balloon tyres are not just cool, they are also a technical tour de force with many advantages:
-
Great riding comfort; because the wide tyres can be ridden with a lower pressure, the suspension factor is a lot higher than with a normal tyre.
-
More grip; the wide tread considerably improves contact with the road.
-
Better puncture resistance; thanks to the higher load capacity, the danger of a puncture is zero.
-
Lower rolling resistance; at the same pressure, wide tyres have a lower rolling resistance than narrower tyres.
-
Higher safety; train and tram rails are no longer a danger.
-
Pump them up less frequently; the lower pressure means the tyre pressure stays longer at the required pressure.
-
Bearing capacity; balloon tyres have a significantly higher load capacity than narrow tyres. In addition, they are highly suitable for tandems or city bikes laden with shopping. Using the tyre pressure, you can easily adjust the suspension to changing weights.
Rollingresistance
The continuous distortion of the material as the tyre rotates causes energy loss. Since the cyclist supplies the energy, it is important that such loss be restricted as much as possible. The rolling resistance is influenced by the following factors:
-
Tyre pressure; the higher the tyre pressure, the less distortion of the tyre.
-
Tyre diameter; tyres with a small diameter have, at an equal pressure, a higher rolling resistance.
-
Tyre width; wide tyres have, at an equal pressure, a lower rolling resistance than narrow tyres. For road tyres, a tyre width of 23 mm provides the best combination of material distortion, air resistance and riding comfort.
-
Profile; on a hard surface, a slick profile has the lowest rolling resistance.
Fitting instructions
Tyres and inner tubes
-
Check the inside of the rim for rust formation to decrease the chance of punctures.
-
Check the correct position of the rim tape.
-
Push one side of the tyre on the rim.
-
Insert the valve stem into the valve hole and gently inflate the inner tube.
-
Push the inner tube over the whole circumference of the wheel inside the tyre.
-
Push the loose side of the tyre into the rim.
-
Push back the valve into the rim for about 2 centimetres and push the tyre bead onto the rim at the valve stem. Then pull the valve out of the rim again as far as possible.
-
Take the wheel in both hands, with the loose side facing towards you. Then push the tyre onto the rim with your thumbs, to the left as well as the right of the valve, while holding the other side of the rim with your fingers. Halfway thru this procedure, you turn the wheel over and push the opposite side of the tyre into the rim.
-
For the final 15 to 20 cm, deflate the air out of the inner tube and mount the remaining section of tyre.
-
Push back the valve as far as possible, then pull it back out of the rim and fit the rim nut.
-
Inflate the tyre to the desired pressure.
-
Finally, check if the tyre bead is positioned properly on the rim.
(Source: Vredestein http://www.vredestein.com)