If your ambient temp is 68 then your cham will bask considerably more than usual. On the coldest day here my ambient dropped to 68 and my chams sprinted for their basking spot when they woke up. I just turned up the heat so that it was a comfortable 73 or 74ish for them and they didn't bask so much. If your cham is basking in an 86 degree basing spot alll day long then his ambient is too low. IMO the only time a cham would bask for super extended period of time, as in hours and hours, is when it is too cold outside the basking spot, when they need to digest a giant meal, when they are fighting off an infection//sick in general or when they are gravid. I'm guessing it is the 68 degree ambient that is doing it. try to get it to 74ish and your cham should move around alot more. Good luck. Oh and make sure to offer his dripper longer/ more often if he is basking so much. Just be sure it is close enough to where he is because I've noticed when it is cold and they are trying to keep warm in their basking spots they don't leave for water unless they are really thirsty, which he may be due to the constant 86 degrees he is under. I think he will be fine once the temps are up a bit.
Justin
EDIT: and lower the basking spot to between 80 and 84. 86 is not burning hot but still a little on the warm side.