I'm on a quest to go faster on my Birdy. I've swapped out the suspension since I'm too heavy for the default suspension at 85kg. I've also replaced the handlebars with a loop bar and that gets me into a reasonably aerodynamic position when I'm on the front at the cost of being a couple centimeters wider when folded.

I spend most of my time in the highest gear so I also have the parts to do a drive train swap from a 10 speed 11-32 trigger shifter to a 11 speed 9-32 thumb shifter. The holdup is that it's nice riding weather and I don't want to have the bike out of commission if it winds up taking longer than expected. Once I do that it'll be a modified Birdy.