my rebound damping seems to be slower since increasing the travel on my reba's from 100 to 120 should i try a heavier weight oil ? also does anyone ever get full travel with correct sag settings ?

Isn't there an adjuster? If not then try EDITheavier lighter oil for sure.

IIRC most forks have "optimistic" travel specs, which include (i.e. do not account for) sag. so a 100mm fork with 20mm sag has 80mm travel. I think.

Heavier oil = slower rebound. lighter oil = faster rebound

I get full travel when the sag is set correctly on most of my forks. the pikes are the exception

IIRC most forks have "optimistic" travel specs, which include (i.e. do not account for) sag. so a 100mm fork with 20mm sag has 80mm travel. I think.

Tosh, the 100mm is the travel, i.e. how far it moves so yes your right 100mm travel is 25-40mm sag and the remainder. But thats how its done, the optimism might come in where you have a bump stop or a very progressive air spring that limits it from reachig the last bit of travel.

You might need to run the rebound slightly quicker when at full travel as the fork has further to extend and a slightly lower spring rate pushing it allong.
Set it for your optimum travel and you'll just have to accpet that tis never going to be perfect at any other point.

ive allways set my rebound to the fastest setting but there seems to be more damping since increasing the travel (slower rebound) my question for sag settings is i never get full travel unless i use 30-40% sag

try the bike with the slower rebound you'll find aslong as it's not packing down you'll have far more grip

i know its probably a personal thing but i've allways thought you set forks fast and rear slower? iam on a hardtail anyway..

Longshot, but did you set the air pressures up at full travel as per instructions. If not, reset them now you are at 120mm