Originally Posted by Beater
The R1100's are not supposed to have the shaft problems of the R100's. Is this the reason? if this is the case, why not replace the swingarm as well? Does the shaft mate differently with the transmission?
The R1100 swingarm and driveshaft are longer. Also, the trans side of the shaft fits on a spline rather than a bolted output flange like on airheads. In order to use an 1100 swingarm on an airhead, you need one of the trans output adapters. Also, you need to create a new shockmount as the oilhead swingarms use a single center mounted shock.