I took the time to register so I could reply to the CR 125 or 500http://www.miniriders.com.au/forum/showthread.php?t=9758 Tumpstar or Cr500thread only to find it closed,found it on cr500riders.com I have a KLX 110 and a crf50 besides what I am about to show you.My Dad built this 1 for himself and it is awesome its an 04 Cr125 with the CR 500 motor
and this bike is his next victim for me an 06 cr125 he is going to put a 500 motor in I can't wait

here is a video of my dad rideing it

click on image to play