Well it would be your pedals striking the ground, not the bottom bracket. And it's unlikely, unless you have a low BB and long cranks. So you can probably do the conversion, but you'll need longer drop brakes too.
@Olly398 started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Well it would be your pedals striking the ground, not the bottom bracket. And it's unlikely, unless you have a low BB and long cranks. So you can probably do the conversion, but you'll need longer drop brakes too.