The BSA A7-A10 Forum

Technical => Frame => Topic started by: Andy51 on 10.08. 2016 21:59

Title: 8 in single sided brake alloy backplate
Post by: Andy51 on 10.08. 2016 21:59
Hi, I am fitting a BSA 8 in single sided brake to an AJS bike.  Thanks for the rim offset info; now another question.  The alloy brake back plate has a 7/16 20 tpi stud for the torque arm between fork leg and backplate.  This stud is fitted through the backplate and is secured by a nut on the inside face, the end of the stud has been peened over to stop the nut loosening; the stud is obviously not intended to be removed in normal service.  How do I replace it?  Is the stud threaded into the alloy with a locknut for security, or is it a push fit, held in by the nut?  Do I file/drill away the peening, remove the nut, lock 2 nuts on the stud and unscrew, or press it out?  Does the stud come loose easily without damaging the softer alloy, or would I be better leaving it in place as the risk of damage is too high?  Thanks, Andy
Title: Re: 8 in single sided brake alloy backplate
Post by: morris on 11.08. 2016 08:11
Hi Andy, the stud is not only secured by the nut on the inside, but also screwed in the alloy.
If I remember well, the part of the stud that screws in the alloy is ww thread. It may also be secured by some Loctite or similar, so can be a real pain to remove
If you decide to remove it make sure that, after removing the inner nut, the thread is in good shape or you'll ruin the thread in the alloy plate.
Title: Re: 8 in single sided brake alloy backplate
Post by: Bsareg on 11.08. 2016 10:06
Hi, if you heat the alloy to to spit & sizzle (tech term) zone, most loctite type products will "let go". Hope this helps. Bsareg