Moto Grand Prix
Main Motorcycle: Triumph Bonneville
Join Date: Oct 2008
Location: Bordeaux, France
Other Motorcycle: Triumph Speedtriple
The kickstart cotter pin should normally just knock out, the way to do it without damaging the threads is to screw an old nut onto it. If it is too mangled, start by cutting off the damaged part to give you a flat(ish) surface to get a drift onto, and then get yourself a LARGE hammer, sometimes a little WD40 or some heat also helps.
Once you've got the kickstaft off, you might find that the shaft has burred over, if it has you will not be able to withdraw the shaft from the gearbox outer cover. I've found the best way to fix this is to grind off the burrs with a dremmel.
As for removing the kickstart shaft from the quadrant, I'm not sure, but you may find it is not necessary, you might just need to put a little more tension on the return spring or maybe a new spring.
I hope this helps