What is the psi recommended for pumping up the tires?

"Look on the sidewall of the tire.

Generally mountain bike tires have a lower pressure than a road bike, but it is important to read the specifications stamped on the tire. Also, if you are riding on the road primarily, you might want a higher pressure to fight rolling resistance.

If you are riding loose dirt, mud and that sort of thing, you might want a slightly lower pressure than what is listing as MAX on the tire. This will give you a better handling bike.

If you are riding a mountain bike on pavement, use slicks or semi-slick tires. These usually have a higher pressure. The specifications depend on the type of tire, and terrain."