How Motorcycle Engines Make 3x More Power (With Half the Engine)

Comments · 135

• PO

  @poetsrevengejoshk1700 · 6 months ago (edited)

  You can sum this all up easily.<br><br>A motorcycle engine being asked to pull a car, even with the weight savings, would be running full load 8-12k rpm to match the output of the car running 3k-4k rpm. &nbsp;It would require detuning compression physically to keep the pistons from destruction. It would last about 1/4 as long.<br><br>You can run a turbo on a smaller engine, to get more power per liter, but the cost again is severe reduction in durability if it&apos;s required to boost under normal use to a high level.<br><br>If you want something to run clean, not destroy it&apos;s self, and actually last 300k MILES like &quot;low&quot; output v8&apos;s in work trucks do , you can&apos;t be at the edge of metal failure at each cycle. &nbsp;The example you chose (coyote) easily lasts 200k in a car, 300k worked at lower rpm&apos;s in a truck. Motorcycles don&apos;t even reach that power &nbsp;level (400+hp) and last about 10-20% as long.<br><br>If you throw durability out the window, you can turbocharge a 1.8L 4cylinder with a stable enough valvetrain, and good enough components, to hit that same 400hp.. but it will actually use MORE fuel at that power level. It will use more fuel at anything over it&apos;s own &quot;most efficient&quot; output point which depending on internal geometry will likely be in the 180-200hp range than the &quot;larger lazy&quot; v8... and it too will, like the motorcycle engine suffer reduced durability. &nbsp;At best motorcycle engines get 30-40k with turbo undersized car engines being in the 100-150k between serious engine work.<br><br>It sums up easy. &nbsp;If you want efficiency and durability, a very EFFICIENT engine turning slow lasts for a lot longer, and runs clean for decades.<br><br>If you want power at a light weight you can trade durability for lighter weight and less displacement. But there is no free lunch.

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• 01

  @01driver · 5 months ago

  This is why I love my zzr1400, &nbsp;the engine does not have to work hard to make me go fast 🙂

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• DA

  @davidbarringham7992 · 6 months ago

  Interesting presentation; thanks! &nbsp;I would also like to see something similar with 2-strokes.

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• KR

  @kraigvanderwyk1153 · 5 months ago

  Despite already knowing, in summary, that more rpm = more hp, but less displacement =less torque, I found the video entertaining and informative. <br>Now if you could make a video explaining the diminishing returns of two stroke displacement versus four stroke displacement I would be educated.

• PE

  @PeteJ1505 · 4 months ago

  Gordon Murray is a notable exception to your reasoning as to why a motorcycle-style engine is unsuitable for a car. He specified and Cosworth designed and built a very high revving short stroke engine for his supercar.

• BA

  @barrywhite4355 · 5 months ago

  I had two Honda cars that had high reving engines, an S600 (even had chain drive to the rear wheels) and a 360cc Zot (water cooled version)

• DA

  @darrelljones8218 · 6 months ago

  Many bike engines if serviced by the book will do in excess of 150,000 mls

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• 2W

  @2wheels4life2 · 5 months ago

  Good info👍 for future projects, thanks.

• RE

  @RetirementVille · 4 months ago

  If you want thrills, exhilaration, noise and blistering speed/acceleration at a low cost, go motorbike. Ignore the fact that they are more dangerous than boxes on wheels...they bring a smile to one face!

• NE

  @NeilCrumpton-w6x · 6 months ago

  Very interesting and well explained. Don&apos;t forget to add Moly powder to the oil to harden the metal surfaces !

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• AM

  @amerhamad-zp6ge · 3 months ago

  The rb17 has a v10 that revvs to 15,000 rpm.

• JV

  @jvillain9946 · 6 months ago (edited)

  The real reason is bc high output motorcycle engines don&apos;t need a lot of torque, like a car engine would and they&apos;re not built to run 100k+ miles. The Honda k series is the closest thing you&apos;ll get to a motorcycle engine in a car. The core layouts are almost identical down to their tilt. The only thing that really changes is the bore is more square and they&apos;re built and tuned for longevity. That&apos;s why you can take a 2L K series and beef it up to 400+ HP. There is also less mechanical loss in motorcycle engines.

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