Yes. It is usually a good idea to replace the set:
Front, Rear and Chain.
Try a different combo...
This really change the dynamic of the bike.
I went from a 17 / 40 combo to a 16 / 40 combo... pretty decent wheelie increase.
Going to a 16 / 42... anticipating lots more wheelie-ability.
However, the top-end will suffer.
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