I've never heard of ISB failures.. only problems I've heard of with cobras is the stock 10 spline input shaft snapping, and possible the TOB retainer sleave coming loose, or in extreme cases snapping the output shaft.


I have not put mine through much torture since the 26 spline and mcleod street twin, but it seems to be holding up fine. When I put the 26 spline in the old input shaft bearing looked pristine (till I fucked it up when I pulled it off )