Unfortunately in my Motocross days, i had a buddy that did all the engine work for me, i did all the suspension, brake, frame, etc. work. Never had much experience in working on engines besides an old Traxxas Nitro 4x4 R/C truck. With the stuff i work on now-a-days, 14' Cincinnati shears and brake presses, 700 ton hydraulic die presses, etc. i'm sure i could figure out a single cylinder motor if i had to... and i'm sure that time will come eventually.
Rustler, stampede or tmaxx? Or nitro sport?