Should handlebar be plural or singular? Here are some sample sentences.
"Start the engine and let it run idle. Move the handlebar to and fro over the entire steering range."
"Move the clutch fluid reservoir mounted on the handlebar to a horizontal position."
"The clutch lever is fitted on the left side of the handlebar."
"Hold the handlebar firmly with both hands."
I've already started a discussion here but there doesn't seem to be a consensus.