sounds like the cables are out of adjustment. If it's cycling over and over it's the servo motor that controls the EXUP valve attempting to complete its limit test. Here are the shop manuals:
http://www.redshift.com/~ray/R_is_for_respect
Check the section about the EXUP valve. There is information in there about how to adjust the cables. Basically, you have to remove the little cover down there, then adjust the slack in both cables such that the tab on the pulley sits between the two marks on the housing when the bike is off. Each cable should have a very slight amount of slack as I recall, but not much. The manual will out line it.
Once it's adjusted properly, then when you turn the bike on, you should see the servo motor move the EXUP valve to both its limits (to the right and then to the left) and complete its test. Once it does that, then the tab should come back to rest in the marks I believe.
From there you are good to go.
Ray
