The Honda Vfr V4 Engine Sound Explained Visually!

Hmmm, maybe this doesn't exactly apply to the VFR1200.   Product specs say "The VFR1200F engine also incorporates a special high-strength Symmetrically Coupled Phase-shift Crankshaft that features a 28-degree crankpin offset that works in concert with the 76-degree Vee angle to essentially negate primary engine vibration for smooth running"  Does anybody know what "Symmetrically Coupled Phase-shift Crankshaft that features a 28-degree crankpin offset" means? I'm assuming it means the 1200 is not a 180 degree crankshaft, so the audio bit is not representative of the 1200 engine?

if you parse out "symmetrically coupled phase-shift crankshaft " you may be able to figure out what that means. i'm still working on parse

FREAKIN AWESOME....thanks for posting this!

re: the symetrically coupled phase-shifting crnk on teh 1200, what that means is that even though your cylinders are not spaced 90* like previousl Honda V4's the engine still maintins perfect primary and secondary balance because the crank pins are offset enough to fool the rotating mass into believing that it is a 90* V4.

That's a great video.  Thanks for posting.  

Since the 1200 has a different firing pattern, it definitely sounds different.  Taking cylinder 1 (for no particular reason) as the starting point, it goes 104 degrees, 256 degrees, 104 degrees, 256 degrees.

Converting that to music notation, it roughly corresponds to eighth notes as well (close enough) but the pattern is different.  

Counting it out, it is like this (with the BANGS in capitals) (and I'm counting the music notes, not cylinders here):

ONE and two AND THREE and four AND ONE and two AND THREE and four AND....

I love it when people visually explain something in detail... I hope the person will do one for the 360º crank V4 thats in the RC30 / RC45...

Hmmm, are either end of that V8 model a representation of a 360 degree crank?

To the best of my memory, the pre 1986 models all had 360 degree cranks.

Excellent post!  Thanks for helping my feeble mind understand,,  :biggrin:

Hmmm, are either end of that V8 model a representation of a 360 degree crank?

Yep that is a 360 degree V8 - the most typical type. 350 Chev, 351 Ford etc.

A 180 degree V8 has a flat plane crank and is generally found in the high end stuff like Ferrari or bespoke racing motors, it's called a flat plane crank V8 because all four big end journals lie in the same plane, whereas a crossplane or 360 crank has journals at 0, 90, 180 and 270 degrees.

[image: v8_crank.jpg]

Great visual and audio representation of how the VFR crank and firing order works!

Cool, I knew there was something different about the sound, but never knew what it was. Now I do, thanks!