ing ▁while ▁keeping ▁out ▁water ; ▁and ▁the ▁du ct s / vent s ▁may ▁be ▁closed ▁or ▁covered ▁in ▁cold ▁weather ▁so ▁the ▁r ider ▁can ▁stay ▁comfortable ▁even ▁without ▁a ▁secondary ▁heat ▁source . ▁ ▁In ▁warm ▁and ▁hot ▁weather , ▁the ▁fair ing ▁provides ▁sun ▁protection , ▁but ▁blocks ▁the ▁r ider ▁from ▁cool ing ▁air , ▁and ▁so ▁may ▁be ▁much ▁war mer ▁for ▁a ▁given ▁level ▁of ▁effort . ▁ ▁In ▁some ▁situations , ▁a ▁r ider ' s ▁power ▁output ▁( for ▁any ▁type ▁of ▁cycle ) ▁is ▁limited ▁by ▁body ▁temperature , ▁and ▁the ▁worse ▁cool ing ▁of ▁a ▁vel om obile ▁can ▁limit ▁the ▁r ider ' s ▁power ▁output ▁more ▁than ▁on ▁an ▁un fa ired ▁cycle . ▁ ▁With ▁an ▁aer od ynamic ▁fair ing , ▁the ▁vel om obile ▁r ider ▁at ▁reduced ▁power ▁output ▁may ▁still ▁be ▁faster ▁than ▁an ▁un fa ired ▁cycle , ▁due ▁to ▁the ▁lower ▁aer od ynamic ▁drag . ▁ ▁Vel om ob iles ▁for ▁cargo ▁use ▁often ▁have ▁heavy ▁frames ▁to ▁carry ▁load , ▁plus ▁the ▁weight ▁of ▁the ▁cargo ▁itself . ▁ ▁In ▁turn , ▁the ▁weight ▁of ▁the ▁fair ing ▁may ▁be ▁relatively ▁less ▁important . ▁ ▁Also , ▁bul ky ▁loads ▁often ▁have ▁poor ▁aer od ynam ics , ▁and ▁so ▁the ▁quality ▁of ▁aer od ynam ics ▁of ▁the ▁fair ing ▁is ▁less ▁important . ▁ ▁This ▁may ▁enable ▁use ▁of ▁a ▁fair ing ▁which ▁in ▁hot ▁weather ▁can ▁be ▁converted