Firing order and more...

Discussion in 'Mechanics Garage' started by Hans Olsson, May 6, 2019.

  1. Hans Olsson

    Hans Olsson New Member

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    As it says above, i wonder about the firing order, the angle between the cylinders and the numbering of the cylinders. The bike is a 2003 VFR 800. Thank you.
     
  2. GreginDenver

    GreginDenver New Member

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    The 720 degrees of rotation ("4 cycle" gasoline engine) in a VFR800 RC46 engine:

    One way to view it: 1-0-1-0-0-1-0-1- (8 times 90 degrees equals 720 degrees of rotation)

    Another way to view it: Cylinder #1 goes boom - 180 degrees - Cylinder #3 goes boom - 270 degrees - Cylinder #2 goes boom - 180 degrees - Cylinder #4 goes boom- 90 degrees - (repeating as necessary to have a really good time)

    If you're sitting on the bike: Left rear cylinder fires first, then right rear cylinder fires second, then left front cylinder fires third, then right front cylinder fires fourth.

    90 degree V-4 engine with a flat-plane crankshaft (exactly the same architecture as 1/2 of a Ferrari V-8 engine, which is why it sounds sooooo good)
     
    Last edited: May 6, 2019
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  3. Hans Olsson

    Hans Olsson New Member

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    Very good explanation, thank you.
    Just to make sure,
    crankshafts turns counterclockwise when viewed from the left?
     
    Last edited: May 6, 2019
  4. GreginDenver

    GreginDenver New Member

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    Yes, that is correct.

    Another way to keep it straight in your mind:

    All Honda VFR engines rotate their crankshafts in the same direction as the wheels rotate when you ride happily down the road.

    (And not to cause confusion, but it might be interesting to know that Honda's SHAFT DRIVEN V4 bikes, the Sabre and the Magna, rotated their crankshafts in the opposite direction of the wheels).

    (And way out on the true-nerd-tech-dork end of the spectrum: For the 2017 MotoGP season Honda changed their RCV213V engine's crankshaft rotation from "same as the wheels" to "opposite of the wheels" in an effort to control the bike's tendency to power-wheelie)
     
    Last edited: May 28, 2019

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