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==Engine power and torque==
{{See also|Dynamometer}}
With power typically being the product of [[force]] and [[speed]], a motorcycle's power and [[torque]] ratings will be highly indicative of its performance. Reported numbers for [[power (physics)|power]] and [[torque]] may however vary from one source to another due to inconsistencies in how testing equipment is calibrated, the method of using that equipment, the conditions during the test, and particularly the ___location that force and speed are being measured at.<ref name=Searle2009>{{citation |last=Searle |first=Dave |magazine=[[Motorcycle Consumer News]] | ___location=Irvine, California |publisher=Aviation News Corp |issn=1073-9408 |title=Measures |page=2 |date=October 2009 |volume=40 |issue=10 |url=http://www.mcnews.com/mcn/editorials/2009OctOpenRd.pdf |accessdate=2010-04-29}}</ref> The power of the engine alone, often called crankshaft power, or power at the crankshaft, will be significantly greater than the power measured at the rear wheel. The amount of power lost due to friction in the transmission (primary drive, gearbox and final drive) depends on the details of the design and construction. Generalizing, a chain drive motorcycle may have some 5-20% less power at the rear wheel than at the crankshaft, while a shaft drive model may lose a little more than that due to greater friction.
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While the crankshaft power excludes these transmission losses, still the measurement is often made elsewhere in the drive-train, often at the rear wheel. A correction for the transmission losses is then applied to the measured values to obtain the crankshaft values. For motorcycles, the reported power and torque numbers normally pertain to the crankshaft. In directive 92/61/EEC of 30 June 1992 relating to the type-approval of two or three-wheel motor vehicles,<ref name="eur-lex.europa.eu">http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0061:EN:HTML</ref> it is referred to as "maximum engine power", and manufacturers use similar terms. Historically, this convention may have come from the pre-[[unit construction]], wherein the crankshaft was directly accessible for measurements, and the gearbox might have come from a different manufacturer. However, when the engineering details of the transmission are known, the losses therein can be accurately quantified & corrected for. Explicit guidance on the homologation measurements and transmission corrections is given in directive 95/1/EC.<ref>http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:1995:052:0001:0040:EN:PDF</ref>
A main source of ambiguity and differences comes from the conditions the test was done at. These conditions include details like atmospheric conditions (temperature, pressure, humidity), tire pressure, but most importantly: the conditions of the motorcycle itself. Examples thereof are: was the alternator fitted?; was the air filter fitted?; what exhaust system was fitted? One would hope that manufacturers would test their motorcycles in normal running order, so the condition that they are sold in, and for which they obtained type-approval, but this is not always the case. Ducati, for instance, has chosen to publish more positive values, stating that "Technical data referring to power and torque was measured on an engine test stand at Ducati".<ref>http://ducati.com/bikes/superbike/1199_panigale_r/tech_spec.do</ref> Their published values are typically 5% higher than the [[homologation]] values, in normal running order.
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===Dry weight===
As its weight changes during riding, the dry weight of a motorcycle typically excludes the [[gasoline]] (or other fuel). Dry weight, in this sense, can directly be used for comparison with (FIM) weight limits, which pertain to the motorcycle in operating condition. It is also part of the homologation tests,<ref
So there is no standardized way to test the dry weight of a motorcycle. Inconsistencies may be found between a motorcycle manufacturer's published dry weight and motorcycle press and media outlet's published dry weight. This is due to different testing techniques, mainly differences in what is being excluded, and a lack of defining how the test was done. A battery is typically included in the dry weight by manufacturers (with the exception of at least one), but it may not be included by media outlets. On the other hand, some press and media outlets only exclude fuel to define their dry weight. For a typical [[sport bike]], the difference between wet weight and manufacturer claimed dry weight is around {{convert|70|lb|kg|abbr=on}}.<ref>[http://www.amadirectlink.com/news/2006/cbr600rr/ Ridden & Reviewed: 2007 Honda CBR600RR<!-- Bot generated title -->]</ref> This difference includes around {{convert|30|lb|kg|abbr=on}} of gasoline, {{convert|7|lb|kg|abbr=on}} of engine oil, {{convert|7|lb|kg|abbr=on}} of coolant, and {{convert|9|lb|kg|abbr=on}} of battery. These weights are even larger for bigger motorcycles with higher capacities, and attempting to compare the dry weights of [[air-cooled]] versus [[water-cooled]] motorcycles can be even more misleading.
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The wet weight of a motorcycle includes, but is not limited to fuel, engine oil, coolant, brake fluid, and battery.
There is no global standardized way to test the wet weight of a motorcycle. In the EU, Council Directive 93/93/EEC specifies wet weight as "mass in running order", which includes all equipment normally fitted to a bike such as windscreen, tool kit and at least 90% of its fuel capacity.<ref>{{cite web | url= http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993L0093:EN:HTML | title= Council Directive 93/93/EEC of 29 October 1993 on the masses and dimensions of two or three-wheel motor vehicles | work=EUR-Lex | accessdate= 14 December 2009}}</ref> Motorcycle manufacturers will rarely publish wet weight measurements and inconsistencies will almost always be found between different motorcycle press and media outlets. This is due to different testing techniques, differences in what is being included, and by the organization doing the testing omitting an explanation of how they weighed the motorcycle.
''[[Cycle World]]'' has published wet weights with all consumables on board, but only half a tank of fuel, while [[Honda]] has recently published specification tables that use the typically automotive-oriented term ''curb weight'', and stated that it included full fluid levels and the bike was "ready to ride."
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* Performance
** Top speed ''see above''
** Acceleration: ''Such as [[0 to 60
** {{convert|0|to|1/4|mi|km|abbr=on}} ''See [[dragstrip]]''
** Braking {{convert|60|to|0|mph|km/h|abbr=on}}, {{convert|100|to|0|mph|km/h|abbr=on}}
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* [[Dry weight (automobile)]]
* [[Rounding]]
* [[
* [[Vehicle metrics]]
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|last=Stermer |year=2006 |first=Bill |title=Streetbikes: Everything You Need to Know |publisher=MotorBooks/MBI Publishing Company |isbn= 9780760323625 |url=http://books.google.com/books?id=NMokiWY6E00C&pg=PA37#v=onepage&q=&f=false |page=37}}
*{{Citation |url= http://books.google.com/books?id=igONw5YZvEUC&pg=RA6-PA40 |title= Aerodynamics 101; What looks fast isn't |magazine=[[Cycle World]] |date= June 1999 |last = Anderson |first= Steve }}
*{{citation|url=http://books.google.com/books?id=l2Zizg8I8p8C&pg=PA129|title=Motorcycle Tuning: Chassis|first=John|last=Robinson
*{{citation|first=Bruce|last=Reeve |date=June 30, 2010|journal=Cycle Canada|via=Sport Rider|url=http://www.sportrider.com/tunnel-vision|title=Tunnel Vision - What makes the Suzuki Hayabusa faster than the more powerful Kawasaki ZX-12R? A visit to the National Research Council wind tunnel provides the answer}}
{{refend}}
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