Does the Cruise Set light not stay on? Does the Cruise ON light come on? A little more information (including background....ie. all of a sudden not working....only worked intermittenly....never worked, etc) helps to diagnose a problem.
But it is most likely a fuse, dirty contacts in the switch, bad microswitch, aftermarket levers not contacting the switch, etc.
When you say "wont stay engaged",do youmean it initially engages then suddenly disengages? Or do you mean it wont engage at all? There are 4 switches to check: clutch lever, brake lever, foot brake, and cruise set switch on the handlebar. If you have aftermarket clutch/brake levers and/or have some slop/wiggle in the levers, chances are that they are not making good contact with the microswitches. Let us know what you find.
ken been there, clutch, hand brake, foot brake. ALSO THROTTLE CANCEL SWITCH. YOU CAN HEAR THEM CLICK, BUT THAT DOESN'T MAKE THEM GOOD. MINE WAS THROTTLE CANCEL SWITCH, ON THE LEFT CARB. CAN'T GET AT IT, SO I JUMPED IT AND IT NOW WORKS, CRUISE SET SWITCH CAN BE DIRTY, U HAVE TO TAKE GRIP APART, UNHOOK ONE THROTTLE CABLE TO GET IT OUT, THE SWITCH COME APART, BUT BE CAREFUL, SMALL SPRING AND BRASS CONTACT IN THERE, THEY WILL FLY OUT.