Hi - just wondering if anyone's tried putting an aircooled KDX (C) engine into a 1986 KX125 frame. The frames appear to be similar, just that the KX comes with rear disc, bolt on subframe and rising rate linkage.
I did this mod in 1987. I put a 86 engine into a 85 model KX 125 frame. The lower and upper engine mounts needed to be remade and the lowers welded. The KDX tank also needed mounts made aswell. other than that it went straight in. I ran 87 125 forks, rear disc set up, KX500 rear shock with high and low speed compression adustment. AWESOME BIKE I loved it and won many races on it.