Speed, yelling "It's exciting!" (3-7)
I believe the answer is:
rip-roaring
'exciting' is the definition.
(thesaurus)
'speed yelling' is the wordplay.
'speed' becomes 'rip' (I've seen this in another clue).
'yelling' becomes 'roaring' (I can't explain this - if you can you should give a lot more credence to this answer).
'rip'+'roaring'='RIP-ROARING'
'it's' is the link.
Can you help me to learn more?
(Other definitions for rip-roaring that I've seen before include "Wild and noisy" , "Exciting, boisterous" .)