i never tried it on an old srx but i did on my vmax 540. huge improvement over the comet102 and crap secondary. the primary was bolt and go (with some tuning ) for the secondary i had to extend the spline on the jackshaft to match that of a newer srx. can't remember what i used for a belt ,i think it was a t-cat belt but not sure. i just searched until i found one that was the same width as the 8dn belt and for a sled that had the same c-c as my vmax. worked great!