I've been searching for a 15T front sprocket for my 2011 CBR250R because I wanted to cruise at slightly reduced rpm. I found that PBI Sprockets is committed to make a sprocket P/N 382-15 for this bike. Apparently when it finally gets to Western Powersports distributor it will also be called P/N 50-38215. I placed an order for this sprocket 2 months ago but so far I've been waiting, and waiting. Maybe they are waiting for more orders to come in before they produce? So if anyone else is considering the same, you might want to go ahead and place order. Other than the low gearing I love this bike.