Front sprockets for *all* Bevel Drive Singles are back in stock including 12 teeth up to and including 17 teeth in 428 chain size (stock 250-350cc) but you can use them on 450 singles as well ESPECIALLY with the NZ chain we sell here at Bevel Heaven as it is so incredibly strong... Yes, we know that 450 singles came with 530 chain size but WHY BOTHER with such a heavy chain and sprocket combination as the 428 chains these days are so strong? [These sprockets are newly made for us by PBR in Italy, an OEM for Ducati].