Transmission Gear Box Set 1990 KTM 500 MX. This product data sheet is originally written in English. Part for sale was removed from a 1990 KTM 500 MX. It is in very nice condition. The gear teeth looks great. Is dirty and needs to be cleaned. We may be able to let you know if it will fit your bike or not. Frame number: VBKMXL205LM600293 Location: 37 RH RH F UPPER. Part for sale is: Transmission Gear Box Set Parts are used. Engine number: 9-56510040 Frame number: VBKMXL205LM600293 Location: 37 RH RH F UPPER.