Question : VLANs and WAN question

Hi Experts,

I've got multiple VLANs on either side of a WAN connection.  The switches on each end are layer 2/3.  I'm having trouble forwarding traffic down to an client like DHCP or even FTP or HTTP.

Here's the setup:

(Main Network)
LAN1 w/ VLANs 30 (10.1.3.x),110 (10.1.10.x),80 (10.1.8.x) on Switch1
     connected to
Router1 with 2 int - FA0 (10.1.3.245) and SER0 (192.168.1.1)
ip route 10.102.0.0 255.255.255 SER0
ip route 0.0.0.0 0.0.0.0 FA0
    going over t1 and connected to
Router2 with 2 int - FA0 (10.102.3.245) and SER0 (192.168.1.2)
ip route 0.0.0.0 0.0.0.0 SER0
     connected to
LAN 2 w/ VLANs 30 (10.102.3.x),110 (10.102.10.x),80 (10.102.8.x) on Switch2
(Remote end)

Now from the remote end I can see all the servers I need to etc..But things like FTP and DHCP do not work well.  I have IP Helper enabled on the VLAN that needs the DHCP from the Main network, which works occasionally but not consistently.  I also need a device on LAN2-VLAN110 to FTP something from LAN1-VLAN30.  I can ping the LAN1-VLAN30 from the device, but FTP doesn't come back?  All devices have their respective VLAN IPs as gateways.

Any ideas would be welcome...I can't figure out where to start....

Answer : VLANs and WAN question

>ip route 0.0.0.0 0.0.0.0 FA0
Don't use an ethernet interface as a default route. Always use the IP address of the next-hop that is directly connected to this interface. Causes all manner of ARP issues and traffic delays. Serial interface is OK because it is not a broadcast interface.
Reference
https://supportforums.cisco.com/message/3030916;jsessionid=7847BCECBB613537104BEC30C4D1669E.node0