Interesting ride home tonight. Five or Six young guys on bikes tried to cut me off around 11:15PM on Frederick Douglass headed towards Macombs. I was running 20-21MPH in the big ring as a livery came up in the left lane preventing them from blocking both lanes. I was able to jump on the the livery's bumper and blow by them. A little hairy clearing the closest guy and getting on the bumper without just slamming into the side of the car or taking young nimrod out. Cut it pretty fine. Not too anxious about it as it seemed like kid stuff, but; it sure was nice to be cooking along at a pretty good clip at the time, not to mention the timely arrival of that livery. Oh, and my rear blinkie, a Cateye TL1000, was malfunctioning. Found this out after covering 150 blocks. Used my helmet back up the rest of the way home. Not sure if I should change my route up or not.