grip coming off need quick fix

clean then off inside and spray them with aerosol hairspray. Clear laquer spray paint works well too. Spray inside the grip and hit them on fast, leave them for a few minutes to set, the chemicals react with the rubber and bond it to the bars. works like magic.
 
if you got some around the house.. 3M makes an adhesive glue in a spray can. its very tacky and doesnt take long to set up.