Heavy metal fan to leave gathering on bike at front (5)
I believe the answer is:
grebo
'heavy metal fan' is the definition.
(I've seen this before)
'leave gathering on bike at front' is the wordplay.
'leave' becomes 'gre' (I can't justify this - if you can you should give a lot more credence to this answer).
'gathering' is an anagram indicator (letters gathered in a new way).
'at front' suggests taking the first letters.
The initial letters of 'on bike' is 'ob'.
'ob' with letters rearranged gives 'bo'.
'gre'+'bo'='GREBO'
'to' is the link.
Can you help me to learn more?
(Other definitions for grebo that I've seen before include "Long-haired youth" , "Heavy metal fan" , "devotee of heavy metal" .)