Motorcycle testing and measurement: Difference between revisions

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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.eu31992L0061">{{cite webCELEX|url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31992L0061:EN:HTML|titletext=EUR-LexCouncil -Directive 31992L006192/61/EEC of 30 June 1992 relating to the type-approval EN|website=eurof two or three-lex.europa.euwheel motor vehicles}}</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:{{CELEX|31995L0001|text=Directive 95/1/eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:EC of the European Parliament and of the Council of 2 February 1995:052:0001:0040:EN:PDF {{Bareon URLthe inline|date=Augustmaximum design speed, maximum torque and maximum net engine power of two or three-wheel motor 2022vehicles}}</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, how the motorcycle is secured against the dyno drum, 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>{{cite web |url=http://ducati.com/bikes/superbike/1199_panigale_r/tech_spec.do |title=Ducati Superbike 1199 Panigale R - Ducati |access-date=2013-06-09 |url-status=dead |archive-url=https://web.archive.org/web/20130704053908/http://www.ducati.com/bikes/superbike/1199_panigale_r/tech_spec.do |archive-date=2013-07-04 }}</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 name="eur-lex.europa.eu31992L0061"/> and it is found on the EC Certificate of Conformity as unladen mass.<ref name="31993L0093">{{cite web CELEX| url31993L0093|text=http:Council Directive 93/93/eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31993L0093:EN:HTMLEEC |of title=EUR-Lex29 -October 31993L00931993 on the masses and dimensions of two or three-wheel ENmotor vehicles}}</ref> This dry weight could also be useful in comparing different models, with different fuel tank capacities. However, manufacturers may also exclude some or all of the following: [[engine oil]], [[coolant]], or [[brake fluid]], and this makes such a comparison difficult. When any of these is excluded, the specified dry weight no longer pertains to the motorcycle in running order. Some manufacturers even exclude the [[Car battery|battery]], notwithstanding the weight of the battery is mainly in solid components (usually lead), not liquid (electrolytes).

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 outlets' 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>{{cite web|url=http://www.amadirectlink.com/news/2006/cbr600rr/|title=American Motorcyclist Association > Home|first=American Motorcyclist|last=Association|website=www.amadirectlink.com}}</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, complicating comparison between [[air-cooled]] and [[water-cooled]] motorcycles' dry weights.

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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 | urlname= 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 | access-date= 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."