Thank you for the information on the factory shock length. I've looked in to the R6 as well not sure I want to notch my frame. The R6 shock has the same travel as stock but is a much better shock from what I've read.You can also fit an R6 shock onto the CBR300. There's documentation on the CBR250 forums about it. Note that due to the piggyback cartridge part you will need to shave off a bit of the frame. i2i measurement should be 295-296mm on the CBR300 shock IIRC.