How do I know if I can replace the 27 inch wheels with 700c wheels on my bike? I recently purchased an 80's Japanese bike off craigslist called "Jupiter King." It has 27 inch tires but I want to switch to 700c for greater wheel/tire selection. I specifically want some nice yellow wheels with yellow rim. Help? I am quite a noob with bikes. Thanks for any help/advice.
You may or may not be able to make that conversion with your existing brake/frame combination. Your brakes will have to reach farther because a 700c wheel is a smidge smaller than a 27 inch wheel. Depending on your setup, that may be possible. I'd recommend borrowing a 700c wheelset from someone to see if you can line it all up. If it all lines up, great. Purchase whatever 700c wheelset strikes your fancy. If not, you may be able to purchase brakes with a longer reach. Some older frames still won't work with 700c wheels even with the longest brakes available. If that's the case for your frame, you're stuck with 27's. 

Personally, if it were me and I couldn't get it to work with the existing brakes, I'd stick with 27 inch wheels. If you start having to swap brakes out, it starts to get iffy and frankly, I think it's more hassle than it's worth. It's a lot easier (and maybe cheaper) to just start hunting for a frame that already has 700s on it.