Well you may have just not tightened them quite enough.. Self tightening? as far as i know deng has designed a good hub that you can change your sprockets easily, just by undoing the lockring, rather than a complete ball ache with screw on hubs. If chinese parts suck, then why is my 6 year old deng frame still running fine? no cracks, never been welded. Edit: wtf has chinese parts got to do with dan ko anyway? tarty stock the same chinese parts lol