The grip is one of the rider’s most important points of contact with a bicycle. If it twists or slides, holding the bar and reaching the brake lever securely becomes harder. Flat handlebars usually use one of two designs: a flexible grip held by a tight friction fit, or a grip secured by a clamp. A worn push-on grip can loosen over time; with a clamp-on design, the fastening bolts need checking.
Before replacing a grip, remove the bar-end plug and identify the fixing. Loosen the collar on a clamp-on grip; a push-on grip can often be eased free with a little isopropyl alcohol or air between the grip and bar. An old grip may sometimes need cutting away, but a blade can damage a carbon-fibre handlebar. Once the grip is off, clean oil and old adhesive residue from the bar.
A small amount of alcohol can help a new push-on grip slide into place; let it evaporate fully before riding, which may take several hours. Position a clamp-on grip and tighten its bolts to the maker’s specified torque. Finally, reinstall the bar-end plug and check by hand that the grip neither twists nor moves outward. If it still cannot be secured, postpone the ride until the grip or damaged part has been replaced.