How do you slide a neoprene sleeve on to bicycle handlebars easily?
If you have access to it, compressed air is very neat to use.
Slide the grips on as far as they'll go, then poke the nozzle of an
air gun between the grip and the bar. When you depress the trigger
the compressed air will make its way in between the bar and the
grip and act as a lubricant, making it easy to slide the grip the
rest of the way on. Another option is to use methylated spirits, or
rubbing alcohol. Pour some over the bar and onto the insides of the
grips, slide them on before the alcohol evaporates. Once the
alcohol is no longer acting as a lube the grips will be secured in
place. Window cleaning detergents may also be used. A third option
is to use hair spray. Spray liberally on the bar and into grip,
slide grip on. Allow to dry(takes days), then ride. Hairspray acts
as a glue, and may require destructive removal if the grips has to
come off. Moisten the handlebar and the inside of the neoprene grip
with liquid dish detergent and slide the grip on the handlebar.
After the detergent dries the grip will remain firmly in place. A
downside of the two latter is that they rely on substances that are
water soluble. A long ride in rain, or a bike parked outside during
rain may develop "squirming grips syndrome". The top two are
somewhat superior in that matter, as they don't add anything water
soluble to the grip/bar interface.