Agree with the comments that you could easily save some money by getting a less expensive bike and use those savings for other trip expenses. I'd also suggest you try some overnight camping outings closer to home using just the gear you plan to have on your trip. Personally I can't see being comfortable overnight without some type of sleeping bag/blanket/etc. and a pad underneath (or possibly a hammock if you're comfortable in one - I'm not). Using a simple tarp by itself can save a pound or two relative to a small tent but doesn't offer protection from insects (or privacy if staying in public campgrounds). Adding netting and some supports loses most of the weight savings but still does generally offer more space than a small tent.

And it wasn't clear what you were planning for meals. As already mentioned, it's nice to have some extra budget available to try the local restaurants. But you can save quite a bit by preparing many of your meals yourself. Some people are fine with food that doesn't need heating, while others really like the flexibility of having a stove and a few other items to be able to do some cooking and prepare coffee/tea/etc.