It can give a bit of help to the free running of gears (6)
I believe the answer is:
grease
'it can give a bit' is the definition.
The definition suggests a singular noun which matches the answer.
'help to the free running of gears' is the wordplay.
'help' becomes 'ease' (easing is a kind of helping).
'to' means one lot of letters go next to another (I've seen this in other clues).
'the free running of gears' becomes 'gr' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ease' put after 'gr' is 'GREASE'.
'of' is the link.
Can you help me to learn more?
(Other definitions for grease that I've seen before include "Musical starring John Travolta and Olivia Newton-John" , "Mechanic (informal)" , "Musical - lubricant" , "Oily lubricant" , "Lubricating agent" .)