Check the shock cord, pulley or limiter line to make sure one of them isn't getting tangled in something else that would prevent the line from freely moving.
Personally I just eliminated the front controls and reran the line for the back seat only. This allowed me to eliminate the extra pulley, the shock cord and that silly limiter line crossing over. Made it all much simpler so if something goes wrong on the water it could be an easy fix. Could also eliminate the back seat control and do the same if your a front seat solo rider.
I did the same for steering.
Also I ran all the lines within plastic tubing to eliminate/slow down any water entry from the rudder lines. Out all day yesterday in rough wind, sailing alone on TI, no more than a pint of water in hull afterwards.

See pictures and especially Matt's diagram for an idea of what your looking for.
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