As Ben mentions, the max tire pressure is 110 psi. The range is 85-110 psi. The 120 number is the TPI or threads per inch. Many consider the TPI And PSI to be interchangeable numbers and usually that is ok. However, since the manufacture list the max PSI as 110, that is what we recommend as well.
Regarding what is best, it depends on where and how you enjoy riding:
Higher PSI allows the bike to ride "faster" and more efficiently because of the lowered rolling resistants that a harder tire provides. HOWEVER, the trade off is comfort; because the tire is harder, you'll feel more of the road.
Lower PSI is ore comfortable because the lower PSI will make the tire more soft, allowing it to absorb of those road bumps, but you'll work a bit harder to overcome the rolling resistance.
Long story short, it all depends on what you want, just as long as you stay within the recommended PSI.
Here is a short article that can provide a little more insight:
Hello all
As Ben mentions, the max tire pressure is 110 psi. The range is 85-110 psi. The 120 number is the TPI or threads per inch. Many consider the TPI And PSI to be interchangeable numbers and usually that is ok. However, since the manufacture list the max PSI as 110, that is what we recommend as well.
Regarding what is best, it depends on where and how you enjoy riding:
Higher PSI allows the bike to ride "faster" and more efficiently because of the lowered rolling resistants that a harder tire provides. HOWEVER, the trade off is comfort; because the tire is harder, you'll feel more of the road.
Lower PSI is ore comfortable because the lower PSI will make the tire more soft, allowing it to absorb of those road bumps, but you'll work a bit harder to overcome the rolling resistance.
Long story short, it all depends on what you want, just as long as you stay within the recommended PSI.
Here is a short article that can provide a little more insight:
https://www.bicycling.com/repair/a20004232/how-to-achieve-the-perfect-bike-tire-pressure/
If you have any more questions, please let us know!
Tony