Accessing network computers on different routers

I have connected a Tenda wireless router to my linksys BEFSR41. The computers that are wirelessly connected to the tenda router can access the internet ok thru the linksys that connects to my cable modem. The problem I have encountered is that I cannot access the the networked computers in either direction that are connected to the different routers. I can “ping” successfully from the wireless computers to the computers on the Linksys but cannot ping from computers on the linksys to the wireless computers on the Tenda. I cannot ping the Tenda router from computers on the linksys.