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Mahindra's New Goldstar 650
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<blockquote data-quote="Magnetoman" data-source="post: 171658" data-attributes="member: 2806"><p>In 2006 'Motor Trend' magazine wrote an article on the development of the Dynojet dyno. </p><p>[URL unfurl="true"]https://www.motortrend.com/how-to/dynojet-chassis-dyno/[/URL]</p><p></p><p>Note the following text from that article: </p><p></p><p><em>no matter what they did, the math never added up. Dynojet's final number-fudge was arbitrarily based on a number from the most powerful road-going motorcycle of the time, the '85 1,200cc Yamaha VMax. The VMax had 145 advertised factory horsepower, which was far above the raw 90hp number spit out by the formula. Meanwhile, existing aftermarket torque-cell engine dynamometers delivered numbers that clustered around 120. Always a pragmatist, Dobeck finally ordered his Chief Engineer to doctor the math so that the Dynojet 100 measured 120 hp for a stock VMax. And that was that: For once and forever, the power of everything else in the world would be relative to the '85 Yamaha VMax and a fudged imaginary number.</em></p><p></p><p>Aside from anything else, I have to wonder how reliable h.p. readings are when made at only 17% of the calibration/fudge-factor. Also, if the fudge-factor was introduced to reproduce the h.p. measured at the engine on a "real" dyno, that "20 rwhp" actually is 20 engine h.p., making the dyno results even more suspect. The BSA engine dyno curve you posted earlier shows 30 h.p., which is 50% greater than the 20. That's a pretty big discrepancy. And the 20 hp that was displayed assumes the dyno used by the guy in the link you gave isn't out of "calibration." </p><p></p><p>Anyway, there are several reasons not to accept those dyno results at face value without additional information about the dyno itself.</p></blockquote><p></p>
[QUOTE="Magnetoman, post: 171658, member: 2806"] In 2006 'Motor Trend' magazine wrote an article on the development of the Dynojet dyno. [URL unfurl="true"]https://www.motortrend.com/how-to/dynojet-chassis-dyno/[/URL] Note the following text from that article: [I]no matter what they did, the math never added up. Dynojet's final number-fudge was arbitrarily based on a number from the most powerful road-going motorcycle of the time, the '85 1,200cc Yamaha VMax. The VMax had 145 advertised factory horsepower, which was far above the raw 90hp number spit out by the formula. Meanwhile, existing aftermarket torque-cell engine dynamometers delivered numbers that clustered around 120. Always a pragmatist, Dobeck finally ordered his Chief Engineer to doctor the math so that the Dynojet 100 measured 120 hp for a stock VMax. And that was that: For once and forever, the power of everything else in the world would be relative to the '85 Yamaha VMax and a fudged imaginary number.[/I] Aside from anything else, I have to wonder how reliable h.p. readings are when made at only 17% of the calibration/fudge-factor. Also, if the fudge-factor was introduced to reproduce the h.p. measured at the engine on a "real" dyno, that "20 rwhp" actually is 20 engine h.p., making the dyno results even more suspect. The BSA engine dyno curve you posted earlier shows 30 h.p., which is 50% greater than the 20. That's a pretty big discrepancy. And the 20 hp that was displayed assumes the dyno used by the guy in the link you gave isn't out of "calibration." Anyway, there are several reasons not to accept those dyno results at face value without additional information about the dyno itself. [/QUOTE]
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