What is the recommended PSI for bicycle tyres?

Look at the side wall of your tyres and you will be able to read the minimum and maximum PSI or Bar you can inflate your tubeless tyres or inner tubes up to.

Try to maintain the correct inflation pressure in your tube to lower the risk of punctures. Pump your tube to the pressure within that range.  If you are aiming for speed, you can inflate your tube right up to the maximum PSI indicated as that will help to reduce the rolling resistance of the tyre.

For better grip, you can let out some air for a more comfortable ride, especially when it is raining. Remember not go below the minimum PSI range recommended as the inner tube can get pinched between the rim and the tyre which can cause punctures. Also, it will be harder to ride a bike when the tyre pressure is too low.

If you enjoy riding your bicycle downhill, during descents, use your brakes in an on-and-off fashion to prevent the rim from been heated up as that could expand the air in your tube and cause a tyre blow-off. That is a good reason not to over inflate your tube.

If you visit Schwalbe’s website, you will find a tyre pressure chart calculated based on body weight and tyre width.

At Silca there is a link to "Tire Pressure Calculator". You can click on it to enter the information required, which includes the terrain you ride on, in order to calculate the PSI you need to inflate your tyres up to.

Some companies supply their pumps with a PSI chart attached. Based on this chart from PumpKing, for tyre size 700X28C, it is safe to pump your tube right up to 73 PSI if you are not able to read the markings on your tyre. 

Over time you will discover the perfect tyre pressure based on your personal experience and adjustment.  To make adjustment, you can start at the lower end of the recommended range and gradually add a few PSI after each ride, up to the maximum PSI recommended.  You can then stick to the inflation that provides you the best comfort and less resistance during rides.

How much air should I have in my fixie bike tyres?

Try to maintain the correct inflation pressure in your tube to lower the risk of punctures. Look at the inflation recommendations marked on the sidewall of your tyre and pump your tube to the pressure within that range.

If you are aiming for speed, you can inflate your tube right up to the maximum PSI indicated as that will help to reduce the rolling resistance of the tyre.

For better grip, you can let out some air for a more comfortable ride, especially when it is raining. Remember not go below the minimum PSI range recommended as the inner tube can get pinched between the rim and the tyre which can cause punctures.

If you enjoy riding your fixie downhill, during descents, use your brakes in an on-and-off fashion to prevent the rim from been heated up as that could expand the air in your tube and cause a tyre blow-off. That is a good reason not to over inflate your tube.

If you visit Schwalbe’s website, you will find a tyre pressure chart calculated based on body weight.

Some companies supply their pumps with a PSI chart attached. So, for fixie tyre of size 700x28C, if you can’t read the markings on your tyre, it is safe to pump your tube right up to 73 PSI .

How do you protect bicycle tyres from cracking?

If you want to protect your bicycle tyres, avoid doing things to them that will age and dry them out and cause them to crack.

You should:

1) keep bicycle indoor to avoid exposure to the sun's heat or rain.

2) use the proper air pressure (PSI) which is noted on the sidewall of your tyres to prevent overstretching them out.

3) not wash your tyres excessively with chemical cleaners that will remove waxes and other chemical compound the manufacturer used to protect the surface. If you like your tyres looking clean and new, shop around for polish or wax for tyres that will protect or prevent dirt and mud from sticking to them easily.

4) ride on your bicycle regularly so that the tyres are stretched to maintain their flexibility.

5) inflate the tyres at least every 2 weeks even if you are not cycling your bicycle.

6) remove and hang your wheels up if you do not plan to cycle for a long period of time to prevent weight of your bicycle sitting on the tyres. You can also find other ways to store your bicycle, eg, hang it up on the ceiling, like what one of my customers is doing as he rides during the weekends and only when he is free.