{{CD Infobox
|#^infoboxcolor1^#     = Petit
|#^infoboxname^#       = Seishun Jidai 1. 2. 3! /<br>Bicycle Daiseikou!
|#^infoboxJapanese^#   = 青春時代 1.2.3!/バイセコー大成功!
|#^infoboxCover^#      = SeishunJidai123-r.jpg
|#^infoboxCaption^#    = 
|#^infoboxtype^#       = #^Single^#
|#^infoboxartist^#     = [[Petitmoni]]
|#^infoboxalbum^#      = [[Zenbu! Petitmoni]]
|#^infoboxreleased^#   = 26 #^July^# 2000
|#^infoboxgenre^#      = J-Pop
|#^infoboxformat^#     = #^CD^# #^Single^#
|#^infoboxlength^#     = 19:47
|#^infoboxlabel^#      = {{LinkBug|zetima}}
|#^infoboxproducer^#   = [[Tsunku]]
|#^infoboxLast^#       = [[Chokotto LOVE]] <small>1#^Ordinalth^# #^Single^# (1999)</small>
|#^infoboxNext^#       = [[BABY! Koi ni KNOCK OUT!]] <small>3#^Ordinalth^# #^Single^# (2001)</small>
}}
'''Seishun Jidai 1. 2. 3! / Bicycle Daiseikou!''' (青春時代 1.2.3!/バイセコー大成功!) 2#^Ordinalth^# #^Single^# [[Petitmoni]].

==#^Tracklist^#==
[[#^File^#:Petitmoni - Seishun Jidai 1.2.3! (MV)|thumb|right|220 px]]
#Seishun Jidai 1.2.3!
#Bicycle Daiseikou!
#Seishun Jidai 1.2.3! (Instrumental)
#Bicycle Daiseikou! (Instrumental)

==#^FeaturedMembers^#==
*[[Yasuda Kei]]
*[[Goto Maki]]
*[[Yoshizawa Hitomi]]

==#^TVPerformances^#==
*[2000.05.28] [[Hello! Morning]]
*[2000.08.06] [[Hello! Morning]] (Last Phrase Karaoke Battle)

==#^ConcertPerformances^#==
;Seishun Jidai 1.2.3!
*[[Hello! Project 2000 Atsumare! Summer Party]]
*[[Hello! Project 2001 Sugoizo! 21seiki]]
;Bicycle Daiseikou!
*[[Morning Musume Concert Tour 2005 Natsu Aki "Baribari Kyoushitsu ~Koharu-chan Irasshai!~"]]

==#^SingleInformation^#==
#^CreditsLyrics^#, #^CreditsComposition^#: [[Tsunku]]
#Seishun Jidai 1.2.3!
#*#^CreditsArrangement^#, #^CreditsKeyboard^#, #^CreditsProgramming^#: [[Maejima Yasuaki]]
#*#^CreditsDrums^#: [[Sano Yasuo]]
#*Wood #^CreditsBass^#: [[Mizutani Hiroaki]]
#*#^CreditsGuitar^#: [[Suzuki Syunsuke]]
#*#^CreditsPercussion^#: [[Ohgmi Gen]]
#*#^CreditsTrumpet^#: [[Sasaki Shiro]] (Bacchus), [[Suzuki Masanori]] (Bacchus)
#*#^CreditsTrombone^#: [[Sano Satoshi]] (Bacchus)
#*#^CreditsTenor^# #^CreditsSaxophone^#, #^CreditsFlute^#: [[Yoshida Osamu]]
#*#^CreditsTurntable^#: [[D.J. Country]]
#*#^CreditsVoice^#: Tsunku, One Coins
#*#^CreditsChorus^#: Petitmoni, Tsunku
#Bicycle Daiseikou!
#*#^CreditsArrangement^#, #^CreditsKeyboard^#, #^CreditsProgramming^#: [[Konishi Takao]]
#*#^CreditsManipulator^#: [[Katsuura Go]]
#*#^CreditsPercussion^#: [[Yamaguchi Tomo]]
#*#^CreditsChorus^#: Petitmoni, Tsunku, MC Kids

==#^OriconChartPositions^#==
{{OriconStart}}
{{OriconWeekOnly|1/268290}}
{{OriconFinish}}

'''#^OriconTotal^#:''' 484,160#^OriconTotalPost^#

==#^ExternalLinks^#==
*#^Discography^#: [https://web.archive.org/web/20100927230124/http://www.helloproject.com/discography/puchimoni/s_002.html Hello! Project (#^archived^#)], [http://www.up-front-works.jp/release/detail/EPCE-5065/ UP-FRONT WORKS], [http://www.tsunku.net/producework.php?Music_ArtistID=51&@DB_ID@=92#01 Tsunku.net]
*#^Wikipedia^#: [http://ja.wikipedia.org/wiki/青春時代1.2.3!/バイセコー大成功! #^Japanese^#]
*#^LinkLyrics^#: [http://projecthello.com/petit/seishun.html Seishun Jidai 1.2.3!], [http://projecthello.com/petit/baisekou.html Bicycle Daiseikou!]
{{Petitmoni}}


[[en:Seishun Jidai 1. 2. 3! / Bicycle Daiseikou!]]
[[ja:青春時代 1.2.3!/バイセコー大成功!]]
[[#^Category^#:#^CatGroupSinglePre^#Petitmoni#^CatGroupSinglePost^#]]
[[#^Category^#:#^CatYearSinglePre^#2000#^CatYearSinglePost^#]]
[[#^Category^#:#^CatMembersLineupPre^#3#^CatMembersLineupPost^#]]
[[#^Category^#:#^CatDoubleASide^#]]