First of all, welcome to the forums!
Those temps sound like they will be alright. Monitor your cham; if he starts gaping he may be too warm under the basking light but at 85* he should be comfortable. It's harder to tell if they are not getting enough heat, however, so for a young cham like yours I've always tried to make sure my basking temp never went below 82.
I would also say make sure you have multiple instruments that you are using to take temperatures and humidity. I never trust one instrument, especially not a cheaply made one.
Also, you mentioned you had one of those day light bulbs over your enclosure. Are you using a uvb/uva light source as well? The well being of your cham depends on you providing a source of ultra violet light (unless your cham recieves natural unfiltered sunlight several times a month) such as a Reptisun 5.0. This is just a standard good choice and there are other appropriate UV lights that would work as well. You may, for all I know, already have a source of UV for your cham I just wanted to stress the importance of it.
Currently, I'm just using a couple standard incandescent 60 watt bulbs installed into domes and a flourescent Reptisun 5.0 running the width of the cage. There is no definitive lighting set up and there are tons of options out there that will potentially work fine... You just have to find what works best for you!
