I am tinkering with a commuter. I have a road bike frame with a 130mm rear dropout. For the sake of simplicity, I want to run an 11-32 rear cassette with a single 44 or 46 tooth single front sprocket crank. Can I run a track bike or SS single sprocket front crank. I guess the concern would be spacing issues off the BB. What should I look for in a rear derailleur?