is it just a tensile load? in which case...the above is pretty simple to get your head around... otherwise..i think the finite difference/element method might be of use...
well i just got a rockman and it seems pretty tip top to answer the above...i've moved from a try-all to a rockman and although I don't think I can tell the difference (perhaps because I had a fair while not riding in between) I'm fairly sure moving from 108 to 60 would have been a shock...