Cocco, Gaetano (2004). «Chapter 11 The Engine». Motorcycle Design and Technology. St. Paul, MN USA: MotorBooks International. p. 117. ISBN0-7603-1990-1. Consultado el 28 de mayo de 2013. «In some construction layouts the transverse width is the same as a single-cylinder engine, which allows very narrow frames and bodywork with small frontal areas.»
Dean, Paul (May 2005). «Service: Oil miser». En Edwards, David, ed. Cycle World (Newport Beach, CA USA: Hachette Filipacchi Media) 44 (5): 160. ISSN0011-4286. Consultado el 26 de mayo de 2013. «An air-cooled big-bore V-twin in particular can get very hot, especially the rear cylinder, which is not exposed to as much cooling air as the front.»
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Dean, Paul (May 2005). «Service: Oil miser». En Edwards, David, ed. Cycle World (Newport Beach, CA USA: Hachette Filipacchi Media) 44 (5): 160. ISSN0011-4286. Consultado el 26 de mayo de 2013. «An air-cooled big-bore V-twin in particular can get very hot, especially the rear cylinder, which is not exposed to as much cooling air as the front.»