M7h,
The NT1 shocks are just an updated version of the old serpent shocks.
RMD,
Open your pistons to 4-holes submerge them in oil, then close and open them a few times before filling the shock with all 4 holes open. After filling the shocks and screwing the caps on they should rebound 100% and feel firm from too much oil. its ok if they have air in them at this point. Let them sit upside down for a few min before bleeding to give the air a chance to rise to the bottom seal. While keeping the shocks upside down, release the bottom cap and slowly pump the piston bleeding the shock and setting your rebound. On your last depression of the piston hold it down secure the bottom cap.
If you did not liberally oil your pistons before assembling them they are probably trapping air in between their halves and will need to be taken apart and oiled before reassembly.
When it comes to tuning the x-ray shocks offer the same permutations as any others they are just quicker and easy to change. What I generally do is build my shocks with a 75% rebound (low grip) using 40wt oil and start with a 3 hole rears and 2 hole fronts. Should the grip come up I can easy close another hole each and reduce my rebound if need be. For an idea on basic shock setups I usually run:
super low grip - 75% rebound, 40wt, 3h-F w/ 22.5lb, 4h-R w/ 20lb.
Low grip - 75% rebound, 40wt, 2h-F w/ 25lb, 3h-R w/ 22.5lb.
med low grip - 50% rebound 40wt, 1h-F w/ 28lb, 2h-R w/ 25lb.
med high grip - 50%-25% rebound, 60wt, 2h-F w/ 30lb, 3h-R w/ 28lb.
high grip - 25% rebound 60wt, 2h-F w/ 33lb, 3h-R w/ 30lb
Mark