I've never changed a sprocket. So I dont know.
Chain.....I remembered was S$40 for a so so chain.
But battery I last remember in the range of $30-$120, depends on
where you ganna 'chop'.
Airfilter? Depends on quality. $8-$100 also have.
Hope they help. Its been 4 years since I rode a
phantom.
ty. yea, air filter. :p anyway, hope u get better. 