My 8 y/o son has been riding for 2 years on a PW 80 which he has now outgrown. I have been debating on the KLX 110, XR-70, TTR90 and now the XR-80. Being that the PW-80 is small for him what bike would be the best choice? I don't want to have to buy a bike every year and would like him to learn a clutch but am unsure if the XR-80 is the best bike to learn on even though he is a good rider but in comparing the other offerings they all are not much bigger then the PW-80...